Android : Glide image loading library | Image Loading Tutorial

#Android #Glide #library implementation is explained in this part of the #tutorial with a example for each variant where we load images from #local #drawable #folder, #image form url and also utilizing the library to modify the image #dimensions.

Also we can add a placeholders to fill the image view until the actual image loads up to the screen.

Source Code : http://www.androidcoding.in/2018/01/07/android-glide-tutorial-image-loading

#android #glide #library

What is GEEK

Buddha Community

Build an Android application with Kivy Python framework

If you’re a Python developer thinking about getting started with mobile development, then the Kivy framework is your best bet. With Kivy, you can develop platform-independent applications that compile for iOS, Android, Windows, macOS, and Linux. In this article, we’ll cover Android specifically because it is the most used.

We’ll build a simple random number generator app that you can install on your phone and test when you are done. To follow along with this article, you should be familiar with Python. Let’s get started!

Getting started with Kivy

First, you’ll need a new directory for your app. Make sure you have Python installed on your machine and open a new Python file. You’ll need to install the Kivy module from your terminal using either of the commands below. To avoid any package conflicts, be sure you’re installing Kivy in a virtual environment:

pip install kivy 
//
pip3 install kivy 

Once you have installed Kivy, you should see a success message from your terminal that looks like the screenshots below:

Kivy installation

Successful Kivy installation

 

Next, navigate into your project folder. In the main.py file, we’ll need to import the Kivy module and specify which version we want. You can use Kivy v2.0.0, but if you have a smartphone that is older than Android 8.0, I recommend using Kivy v1.9.0. You can mess around with the different versions during the build to see the differences in features and performance.

Add the version number right after the import kivy line as follows:

kivy.require('1.9.0')

Now, we’ll create a class that will basically define our app; I’ll name mine RandomNumber. This class will inherit the app class from Kivy. Therefore, you need to import the app by adding from kivy.app import App:

class RandomNumber(App): 

In the RandomNumber class, you’ll need to add a function called build, which takes a self parameter. To actually return the UI, we’ll use the build function. For now, I have it returned as a simple label. To do so, you’ll need to import Label using the line from kivy.uix.label import Label:

import kivy
from kivy.app import App
from kivy.uix.label import Label

class RandomNumber(App):
  def build(self):
    return Label(text="Random Number Generator")

Now, our app skeleton is complete! Before moving forward, you should create an instance of the RandomNumber class and run it in your terminal or IDE to see the interface:

import kivy from kivy.app import App from kivy.uix.label import Label class RandomNumber(App):  def build(self):    return Label(text="Random Number Generator") randomApp = RandomNumber() randomApp.run()

When you run the class instance with the text Random Number Generator, you should see a simple interface or window that looks like the screenshot below:

 

Simple interface after running the code

You won’t be able to run the text on Android until you’ve finished building the whole thing.

Outsourcing the interface

Next, we’ll need a way to outsource the interface. First, we’ll create a Kivy file in our directory that will house most of our design work. You’ll want to name this file the same name as your class using lowercase letters and a .kv extension. Kivy will automatically associate the class name and the file name, but it may not work on Android if they are exactly the same.

Inside that .kv file, you need to specify the layout for your app, including elements like the label, buttons, forms, etc. To keep this demonstration simple, I’ll add a label for the title Random Number, a label that will serve as a placeholder for the random number that is generated _, and a Generate button that calls the generate function.

My .kv file looks like the code below, but you can mess around with the different values to fit your requirements:

<boxLayout>:
    orientation: "vertical"
    Label:
        text: "Random Number"
        font_size: 30
        color: 0, 0.62, 0.96

    Label:
        text: "_"
        font_size: 30

    Button:
        text: "Generate"
        font_size: 15 

In the main.py file, you no longer need the Label import statement because the Kivy file takes care of your UI. However, you do need to import boxlayout, which you will use in the Kivy file.

In your main file, you need to add the import statement and edit your main.py file to read return BoxLayout() in the build method:

from kivy.uix.boxlayout import BoxLayout

If you run the command above, you should see a simple interface that has the random number title, the _ place holder, and the clickable generate button:

Random Number app rendered

Notice that you didn’t have to import anything for the Kivy file to work. Basically, when you run the app, it returns boxlayout by looking for a file inside the Kivy file with the same name as your class. Keep in mind, this is a simple interface, and you can make your app as robust as you want. Be sure to check out the Kv language documentation.

Generate the random number function

Now that our app is almost done, we’ll need a simple function to generate random numbers when a user clicks the generate button, then render that random number into the app interface. To do so, we’ll need to change a few things in our files.

First, we’ll import the module that we’ll use to generate a random number with import random. Then, we’ll create a function or method that calls the generated number. For this demonstration, I’ll use a range between 0 and 2000. Generating the random number is simple with the random.randint(0, 2000) command. We’ll add this into our code in a moment.

Next, we’ll create another class that will be our own version of the box layout. Our class will have to inherit the box layout class, which houses the method to generate random numbers and render them on the interface:

class MyRoot(BoxLayout):
    def __init__(self):
        super(MyRoot, self).__init__()

Within that class, we’ll create the generate method, which will not only generate random numbers but also manipulate the label that controls what is displayed as the random number in the Kivy file.

To accommodate this method, we’ll first need to make changes to the .kv file . Since the MyRoot class has inherited the box layout, you can make MyRoot the top level element in your .kv file:

<MyRoot>:
    BoxLayout:
        orientation: "vertical"
        Label:
            text: "Random Number"
            font_size: 30
            color: 0, 0.62, 0.96

        Label:
            text: "_"
            font_size: 30

        Button:
            text: "Generate"
            font_size: 15

Notice that you are still keeping all your UI specifications indented in the Box Layout. After this, you need to add an ID to the label that will hold the generated numbers, making it easy to manipulate when the generate function is called. You need to specify the relationship between the ID in this file and another in the main code at the top, just before the BoxLayout line:

<MyRoot>:
    random_label: random_label
    BoxLayout:
        orientation: "vertical"
        Label:
            text: "Random Number"
            font_size: 30
            color: 0, 0.62, 0.96

        Label:
            id: random_label
            text: "_"
            font_size: 30

        Button:
            text: "Generate"
            font_size: 15

The random_label: random_label line basically means that the label with the ID random_label will be mapped to random_label in the main.py file, meaning that any action that manipulates random_label will be mapped on the label with the specified name.

We can now create the method to generate the random number in the main file:

def generate_number(self):
    self.random_label.text = str(random.randint(0, 2000))

# notice how the class method manipulates the text attributre of the random label by a# ssigning it a new random number generate by the 'random.randint(0, 2000)' funcion. S# ince this the random number generated is an integer, typecasting is required to make # it a string otherwise you will get a typeError in your terminal when you run it.

The MyRoot class should look like the code below:

class MyRoot(BoxLayout):
    def __init__(self):
        super(MyRoot, self).__init__()

    def generate_number(self):
        self.random_label.text = str(random.randint(0, 2000))

Congratulations! You’re now done with the main file of the app. The only thing left to do is make sure that you call this function when the generate button is clicked. You need only add the line on_press: root.generate_number() to the button selection part of your .kv file:

<MyRoot>:
    random_label: random_label
    BoxLayout:
        orientation: "vertical"
        Label:
            text: "Random Number"
            font_size: 30
            color: 0, 0.62, 0.96

        Label:
            id: random_label
            text: "_"
            font_size: 30

        Button:
            text: "Generate"
            font_size: 15
            on_press: root.generate_number()

Now, you can run the app.

Compiling our app on Android

Before compiling our app on Android, I have some bad news for Windows users. You’ll need Linux or macOS to compile your Android application. However, you don’t need to have a separate Linux distribution, instead, you can use a virtual machine.

To compile and generate a full Android .apk application, we’ll use a tool called Buildozer. Let’s install Buildozer through our terminal using one of the commands below:

pip3 install buildozer
//
pip install buildozer

Now, we’ll install some of Buildozer’s required dependencies. I am on Linux Ergo, so I’ll use Linux-specific commands. You should execute these commands one by one:

sudo apt update
sudo apt install -y git zip unzip openjdk-13-jdk python3-pip autoconf libtool pkg-config zlib1g-dev libncurses5-dev libncursesw5-dev libtinfo5 cmake libffi-dev libssl-dev

pip3 install --upgrade Cython==0.29.19 virtualenv 

# add the following line at the end of your ~/.bashrc file
export PATH=$PATH:~/.local/bin/

After executing the specific commands, run buildozer init. You should see an output similar to the screenshot below:

Buildozer successful initialization

The command above creates a Buildozer .spec file, which you can use to make specifications to your app, including the name of the app, the icon, etc. The .spec file should look like the code block below:

[app]

# (str) Title of your application
title = My Application

# (str) Package name
package.name = myapp

# (str) Package domain (needed for android/ios packaging)
package.domain = org.test

# (str) Source code where the main.py live
source.dir = .

# (list) Source files to include (let empty to include all the files)
source.include_exts = py,png,jpg,kv,atlas

# (list) List of inclusions using pattern matching
#source.include_patterns = assets/*,images/*.png

# (list) Source files to exclude (let empty to not exclude anything)
#source.exclude_exts = spec

# (list) List of directory to exclude (let empty to not exclude anything)
#source.exclude_dirs = tests, bin

# (list) List of exclusions using pattern matching
#source.exclude_patterns = license,images/*/*.jpg

# (str) Application versioning (method 1)
version = 0.1

# (str) Application versioning (method 2)
# version.regex = __version__ = \['"\](.*)['"]
# version.filename = %(source.dir)s/main.py

# (list) Application requirements
# comma separated e.g. requirements = sqlite3,kivy
requirements = python3,kivy

# (str) Custom source folders for requirements
# Sets custom source for any requirements with recipes
# requirements.source.kivy = ../../kivy

# (list) Garden requirements
#garden_requirements =

# (str) Presplash of the application
#presplash.filename = %(source.dir)s/data/presplash.png

# (str) Icon of the application
#icon.filename = %(source.dir)s/data/icon.png

# (str) Supported orientation (one of landscape, sensorLandscape, portrait or all)
orientation = portrait

# (list) List of service to declare
#services = NAME:ENTRYPOINT_TO_PY,NAME2:ENTRYPOINT2_TO_PY

#
# OSX Specific
#

#
# author = © Copyright Info

# change the major version of python used by the app
osx.python_version = 3

# Kivy version to use
osx.kivy_version = 1.9.1

#
# Android specific
#

# (bool) Indicate if the application should be fullscreen or not
fullscreen = 0

# (string) Presplash background color (for new android toolchain)
# Supported formats are: #RRGGBB #AARRGGBB or one of the following names:
# red, blue, green, black, white, gray, cyan, magenta, yellow, lightgray,
# darkgray, grey, lightgrey, darkgrey, aqua, fuchsia, lime, maroon, navy,
# olive, purple, silver, teal.
#android.presplash_color = #FFFFFF

# (list) Permissions
#android.permissions = INTERNET

# (int) Target Android API, should be as high as possible.
#android.api = 27

# (int) Minimum API your APK will support.
#android.minapi = 21

# (int) Android SDK version to use
#android.sdk = 20

# (str) Android NDK version to use
#android.ndk = 19b

# (int) Android NDK API to use. This is the minimum API your app will support, it should usually match android.minapi.
#android.ndk_api = 21

# (bool) Use --private data storage (True) or --dir public storage (False)
#android.private_storage = True

# (str) Android NDK directory (if empty, it will be automatically downloaded.)
#android.ndk_path =

# (str) Android SDK directory (if empty, it will be automatically downloaded.)
#android.sdk_path =

# (str) ANT directory (if empty, it will be automatically downloaded.)
#android.ant_path =

# (bool) If True, then skip trying to update the Android sdk
# This can be useful to avoid excess Internet downloads or save time
# when an update is due and you just want to test/build your package
# android.skip_update = False

# (bool) If True, then automatically accept SDK license
# agreements. This is intended for automation only. If set to False,
# the default, you will be shown the license when first running
# buildozer.
# android.accept_sdk_license = False

# (str) Android entry point, default is ok for Kivy-based app
#android.entrypoint = org.renpy.android.PythonActivity

# (str) Android app theme, default is ok for Kivy-based app
# android.apptheme = "@android:style/Theme.NoTitleBar"

# (list) Pattern to whitelist for the whole project
#android.whitelist =

# (str) Path to a custom whitelist file
#android.whitelist_src =

# (str) Path to a custom blacklist file
#android.blacklist_src =

# (list) List of Java .jar files to add to the libs so that pyjnius can access
# their classes. Don't add jars that you do not need, since extra jars can slow
# down the build process. Allows wildcards matching, for example:
# OUYA-ODK/libs/*.jar
#android.add_jars = foo.jar,bar.jar,path/to/more/*.jar

# (list) List of Java files to add to the android project (can be java or a
# directory containing the files)
#android.add_src =

# (list) Android AAR archives to add (currently works only with sdl2_gradle
# bootstrap)
#android.add_aars =

# (list) Gradle dependencies to add (currently works only with sdl2_gradle
# bootstrap)
#android.gradle_dependencies =

# (list) add java compile options
# this can for example be necessary when importing certain java libraries using the 'android.gradle_dependencies' option
# see https://developer.android.com/studio/write/java8-support for further information
# android.add_compile_options = "sourceCompatibility = 1.8", "targetCompatibility = 1.8"

# (list) Gradle repositories to add {can be necessary for some android.gradle_dependencies}
# please enclose in double quotes 
# e.g. android.gradle_repositories = "maven { url 'https://kotlin.bintray.com/ktor' }"
#android.add_gradle_repositories =

# (list) packaging options to add 
# see https://google.github.io/android-gradle-dsl/current/com.android.build.gradle.internal.dsl.PackagingOptions.html
# can be necessary to solve conflicts in gradle_dependencies
# please enclose in double quotes 
# e.g. android.add_packaging_options = "exclude 'META-INF/common.kotlin_module'", "exclude 'META-INF/*.kotlin_module'"
#android.add_gradle_repositories =

# (list) Java classes to add as activities to the manifest.
#android.add_activities = com.example.ExampleActivity

# (str) OUYA Console category. Should be one of GAME or APP
# If you leave this blank, OUYA support will not be enabled
#android.ouya.category = GAME

# (str) Filename of OUYA Console icon. It must be a 732x412 png image.
#android.ouya.icon.filename = %(source.dir)s/data/ouya_icon.png

# (str) XML file to include as an intent filters in <activity> tag
#android.manifest.intent_filters =

# (str) launchMode to set for the main activity
#android.manifest.launch_mode = standard

# (list) Android additional libraries to copy into libs/armeabi
#android.add_libs_armeabi = libs/android/*.so
#android.add_libs_armeabi_v7a = libs/android-v7/*.so
#android.add_libs_arm64_v8a = libs/android-v8/*.so
#android.add_libs_x86 = libs/android-x86/*.so
#android.add_libs_mips = libs/android-mips/*.so

# (bool) Indicate whether the screen should stay on
# Don't forget to add the WAKE_LOCK permission if you set this to True
#android.wakelock = False

# (list) Android application meta-data to set (key=value format)
#android.meta_data =

# (list) Android library project to add (will be added in the
# project.properties automatically.)
#android.library_references =

# (list) Android shared libraries which will be added to AndroidManifest.xml using <uses-library> tag
#android.uses_library =

# (str) Android logcat filters to use
#android.logcat_filters = *:S python:D

# (bool) Copy library instead of making a libpymodules.so
#android.copy_libs = 1

# (str) The Android arch to build for, choices: armeabi-v7a, arm64-v8a, x86, x86_64
android.arch = armeabi-v7a

# (int) overrides automatic versionCode computation (used in build.gradle)
# this is not the same as app version and should only be edited if you know what you're doing
# android.numeric_version = 1

#
# Python for android (p4a) specific
#

# (str) python-for-android fork to use, defaults to upstream (kivy)
#p4a.fork = kivy

# (str) python-for-android branch to use, defaults to master
#p4a.branch = master

# (str) python-for-android git clone directory (if empty, it will be automatically cloned from github)
#p4a.source_dir =

# (str) The directory in which python-for-android should look for your own build recipes (if any)
#p4a.local_recipes =

# (str) Filename to the hook for p4a
#p4a.hook =

# (str) Bootstrap to use for android builds
# p4a.bootstrap = sdl2

# (int) port number to specify an explicit --port= p4a argument (eg for bootstrap flask)
#p4a.port =


#
# iOS specific
#

# (str) Path to a custom kivy-ios folder
#ios.kivy_ios_dir = ../kivy-ios
# Alternately, specify the URL and branch of a git checkout:
ios.kivy_ios_url = https://github.com/kivy/kivy-ios
ios.kivy_ios_branch = master

# Another platform dependency: ios-deploy
# Uncomment to use a custom checkout
#ios.ios_deploy_dir = ../ios_deploy
# Or specify URL and branch
ios.ios_deploy_url = https://github.com/phonegap/ios-deploy
ios.ios_deploy_branch = 1.7.0

# (str) Name of the certificate to use for signing the debug version
# Get a list of available identities: buildozer ios list_identities
#ios.codesign.debug = "iPhone Developer: <lastname> <firstname> (<hexstring>)"

# (str) Name of the certificate to use for signing the release version
#ios.codesign.release = %(ios.codesign.debug)s


[buildozer]

# (int) Log level (0 = error only, 1 = info, 2 = debug (with command output))
log_level = 2

# (int) Display warning if buildozer is run as root (0 = False, 1 = True)
warn_on_root = 1

# (str) Path to build artifact storage, absolute or relative to spec file
# build_dir = ./.buildozer

# (str) Path to build output (i.e. .apk, .ipa) storage
# bin_dir = ./bin

#    -----------------------------------------------------------------------------
#    List as sections
#
#    You can define all the "list" as [section:key].
#    Each line will be considered as a option to the list.
#    Let's take [app] / source.exclude_patterns.
#    Instead of doing:
#
#[app]
#source.exclude_patterns = license,data/audio/*.wav,data/images/original/*
#
#    This can be translated into:
#
#[app:source.exclude_patterns]
#license
#data/audio/*.wav
#data/images/original/*
#


#    -----------------------------------------------------------------------------
#    Profiles
#
#    You can extend section / key with a profile
#    For example, you want to deploy a demo version of your application without
#    HD content. You could first change the title to add "(demo)" in the name
#    and extend the excluded directories to remove the HD content.
#
#[app@demo]
#title = My Application (demo)
#
#[app:source.exclude_patterns@demo]
#images/hd/*
#
#    Then, invoke the command line with the "demo" profile:
#
#buildozer --profile demo android debug

If you want to specify things like the icon, requirements, loading screen, etc., you should edit this file. After making all the desired edits to your application, run buildozer -v android debug from your app directory to build and compile your application. This may take a while, especially if you have a slow machine.

After the process is done, your terminal should have some logs, one confirming that the build was successful:

Android successful build

You should also have an APK version of your app in your bin directory. This is the application executable that you will install and run on your phone:

Android .apk in the bin directory

Conclusion

Congratulations! If you have followed this tutorial step by step, you should have a simple random number generator app on your phone. Play around with it and tweak some values, then rebuild. Running the rebuild will not take as much time as the first build.

As you can see, building a mobile application with Python is fairly straightforward, as long as you are familiar with the framework or module you are working with. Regardless, the logic is executed the same way.

Get familiar with the Kivy module and it’s widgets. You can never know everything all at once. You only need to find a project and get your feet wet as early as possible. Happy coding.

Link: https://blog.logrocket.com/build-android-application-kivy-python-framework/

#python 

Cree Una Aplicación De Android Con El Marco Kivy Python

Si es un desarrollador de Python que está pensando en comenzar con el desarrollo móvil, entonces el marco Kivy es su mejor opción. Con Kivy, puede desarrollar aplicaciones independientes de la plataforma que compilan para iOS, Android, Windows, macOS y Linux. En este artículo, cubriremos Android específicamente porque es el más utilizado.

Construiremos una aplicación generadora de números aleatorios simple que puede instalar en su teléfono y probar cuando haya terminado. Para continuar con este artículo, debe estar familiarizado con Python. ¡Empecemos!

Primeros pasos con Kivy

Primero, necesitará un nuevo directorio para su aplicación. Asegúrese de tener Python instalado en su máquina y abra un nuevo archivo de Python. Deberá instalar el módulo Kivy desde su terminal usando cualquiera de los comandos a continuación. Para evitar conflictos de paquetes, asegúrese de instalar Kivy en un entorno virtual:

pip install kivy 
//
pip3 install kivy 

Una vez que haya instalado Kivy, debería ver un mensaje de éxito de su terminal que se parece a las capturas de pantalla a continuación:

Instalación decepcionada

Instalación exitosa de Kivy

 

A continuación, navegue a la carpeta de su proyecto. En el main.pyarchivo, necesitaremos importar el módulo Kivy y especificar qué versión queremos. Puede usar Kivy v2.0.0, pero si tiene un teléfono inteligente anterior a Android 8.0, le recomiendo usar Kivy v1.9.0. Puede jugar con las diferentes versiones durante la compilación para ver las diferencias en las características y el rendimiento.

Agregue el número de versión justo después de la import kivylínea de la siguiente manera:

kivy.require('1.9.0')

Ahora, crearemos una clase que básicamente definirá nuestra aplicación; Voy a nombrar el mío RandomNumber. Esta clase heredará la appclase de Kivy. Por lo tanto, debe importar appagregando from kivy.app import App:

class RandomNumber(App): 

En la RandomNumberclase, deberá agregar una función llamada build, que toma un selfparámetro. Para devolver la interfaz de usuario, usaremos la buildfunción. Por ahora, lo tengo devuelto como una simple etiqueta. Para hacerlo, deberá importar Labelusando la línea from kivy.uix.label import Label:

import kivy
from kivy.app import App
from kivy.uix.label import Label

class RandomNumber(App):
  def build(self):
    return Label(text="Random Number Generator")

¡Ahora, el esqueleto de nuestra aplicación está completo! Antes de continuar, debe crear una instancia de la RandomNumberclase y ejecutarla en su terminal o IDE para ver la interfaz:

importar kivy de kivy.app importar aplicación de kivy.uix.label clase de etiqueta de importación RandomNumber(App): def build(self): return Label(text="Generador de números aleatorios") randomApp = RandomNumber() randomApp.run()

Cuando ejecuta la instancia de clase con el texto Random Number Generator, debería ver una interfaz o ventana simple que se parece a la siguiente captura de pantalla:

 

Interfaz simple después de ejecutar el código.

No podrá ejecutar el texto en Android hasta que haya terminado de construir todo.

Externalización de la interfaz

A continuación, necesitaremos una forma de subcontratar la interfaz. Primero, crearemos un archivo Kivy en nuestro directorio que albergará la mayor parte de nuestro trabajo de diseño. Querrá nombrar este archivo con el mismo nombre que su clase usando letras minúsculas y una .kvextensión. Kivy asociará automáticamente el nombre de la clase y el nombre del archivo, pero es posible que no funcione en Android si son exactamente iguales.

Dentro de ese .kvarchivo, debe especificar el diseño de su aplicación, incluidos elementos como la etiqueta, los botones, los formularios, etc. Para simplificar esta demostración, agregaré una etiqueta para el título Random Number, una etiqueta que servirá como marcador de posición. para el número aleatorio que se genera _, y un Generatebotón que llama a la generatefunción.

Mi .kvarchivo se parece al siguiente código, pero puede jugar con los diferentes valores para que se ajusten a sus requisitos:

<boxLayout>:
    orientation: "vertical"
    Label:
        text: "Random Number"
        font_size: 30
        color: 0, 0.62, 0.96

    Label:
        text: "_"
        font_size: 30

    Button:
        text: "Generate"
        font_size: 15 

En el main.pyarchivo, ya no necesita la Labeldeclaración de importación porque el archivo Kivy se encarga de su interfaz de usuario. Sin embargo, necesita importar boxlayout, que utilizará en el archivo Kivy.

En su archivo principal, debe agregar la declaración de importación y editar su main.pyarchivo para leer return BoxLayout()el buildmétodo:

from kivy.uix.boxlayout import BoxLayout

Si ejecuta el comando anterior, debería ver una interfaz simple que tiene el título del número aleatorio, el _marcador de posición y el generatebotón en el que se puede hacer clic:

Aplicación de números aleatorios renderizada

Tenga en cuenta que no tuvo que importar nada para que funcione el archivo Kivy. Básicamente, cuando ejecuta la aplicación, regresa boxlayoutbuscando un archivo dentro del archivo Kivy con el mismo nombre que su clase. Tenga en cuenta que esta es una interfaz simple y puede hacer que su aplicación sea tan robusta como desee. Asegúrese de consultar la documentación del idioma Kv .

Generar la función de números aleatorios

Ahora que nuestra aplicación está casi terminada, necesitaremos una función simple para generar números aleatorios cuando un usuario haga clic en el generatebotón y luego mostrar ese número aleatorio en la interfaz de la aplicación. Para hacerlo, necesitaremos cambiar algunas cosas en nuestros archivos.

Primero, importaremos el módulo que usaremos para generar un número aleatorio con import random. Luego, crearemos una función o método que llame al número generado. Para esta demostración, usaré un rango entre 0y 2000. Generar el número aleatorio es simple con el random.randint(0, 2000)comando. Agregaremos esto a nuestro código en un momento.

A continuación, crearemos otra clase que será nuestra propia versión del box layout. Nuestra clase tendrá que heredar la box layoutclase, que alberga el método para generar números aleatorios y representarlos en la interfaz:

class MyRoot(BoxLayout):
    def __init__(self):
        super(MyRoot, self).__init__()

Dentro de esa clase, crearemos el generatemétodo, que no solo generará números aleatorios, sino que también manipulará la etiqueta que controla lo que se muestra como número aleatorio en el archivo Kivy.

Para acomodar este método, primero necesitaremos hacer cambios en el .kvarchivo. Dado que la MyRootclase ha heredado el box layout, puede crear MyRootel elemento de nivel superior en su .kvarchivo:

<MyRoot>:
    BoxLayout:
        orientation: "vertical"
        Label:
            text: "Random Number"
            font_size: 30
            color: 0, 0.62, 0.96

        Label:
            text: "_"
            font_size: 30

        Button:
            text: "Generate"
            font_size: 15

Tenga en cuenta que todavía mantiene todas las especificaciones de la interfaz de usuario con sangría en el archivo Box Layout. Después de esto, debe agregar una identificación a la etiqueta que contendrá los números generados, lo que facilita la manipulación cuando generatese llama a la función. Debe especificar la relación entre la ID en este archivo y otra en el código principal en la parte superior, justo antes de la BoxLayoutlínea:

<MyRoot>:
    random_label: random_label
    BoxLayout:
        orientation: "vertical"
        Label:
            text: "Random Number"
            font_size: 30
            color: 0, 0.62, 0.96

        Label:
            id: random_label
            text: "_"
            font_size: 30

        Button:
            text: "Generate"
            font_size: 15

La random_label: random_labellínea básicamente significa que la etiqueta con el ID random_labelse asignará a random_labelen el main.pyarchivo, lo que significa que cualquier acción que manipula random_labelserán mapeados en la etiqueta con el nombre especificado.

Ahora podemos crear el método para generar el número aleatorio en el archivo principal:

def generate_number(self):
    self.random_label.text = str(random.randint(0, 2000))

# notice how the class method manipulates the text attributre of the random label by a# ssigning it a new random number generate by the 'random.randint(0, 2000)' funcion. S# ince this the random number generated is an integer, typecasting is required to make # it a string otherwise you will get a typeError in your terminal when you run it.

La MyRootclase debería parecerse al siguiente código:

class MyRoot(BoxLayout):
    def __init__(self):
        super(MyRoot, self).__init__()

    def generate_number(self):
        self.random_label.text = str(random.randint(0, 2000))

¡Felicidades! Ya ha terminado con el archivo principal de la aplicación. Lo único que queda por hacer es asegurarse de llamar a esta función cuando se haga generateclic en el botón. Solo necesita agregar la línea on_press: root.generate_number()a la parte de selección de botones de su .kvarchivo:

<MyRoot>:
    random_label: random_label
    BoxLayout:
        orientation: "vertical"
        Label:
            text: "Random Number"
            font_size: 30
            color: 0, 0.62, 0.96

        Label:
            id: random_label
            text: "_"
            font_size: 30

        Button:
            text: "Generate"
            font_size: 15
            on_press: root.generate_number()

Ahora, puede ejecutar la aplicación.

Compilando nuestra aplicación en Android

Antes de compilar nuestra aplicación en Android, tengo malas noticias para los usuarios de Windows. Necesitará Linux o macOS para compilar su aplicación de Android. Sin embargo, no necesita tener una distribución de Linux separada, en su lugar, puede usar una máquina virtual.

Para compilar y generar una .apkaplicación Android completa , usaremos una herramienta llamada Buildozer . Instalemos Buildozer a través de nuestra terminal usando uno de los siguientes comandos:

pip3 install buildozer
//
pip install buildozer

Ahora, instalaremos algunas de las dependencias requeridas de Buildozer. Estoy en Linux Ergo, así que usaré comandos específicos de Linux. Debe ejecutar estos comandos uno por uno:

sudo apt update
sudo apt install -y git zip unzip openjdk-13-jdk python3-pip autoconf libtool pkg-config zlib1g-dev libncurses5-dev libncursesw5-dev libtinfo5 cmake libffi-dev libssl-dev

pip3 install --upgrade Cython==0.29.19 virtualenv 

# add the following line at the end of your ~/.bashrc file
export PATH=$PATH:~/.local/bin/

Después de ejecutar los comandos específicos, ejecute buildozer init. Debería ver un resultado similar a la captura de pantalla a continuación:

Inicialización exitosa de Buildozer

El comando anterior crea un .specarchivo Buildozer , que puede usar para hacer especificaciones para su aplicación, incluido el nombre de la aplicación, el ícono, etc. El .specarchivo debe verse como el bloque de código a continuación:

[app]

# (str) Title of your application
title = My Application

# (str) Package name
package.name = myapp

# (str) Package domain (needed for android/ios packaging)
package.domain = org.test

# (str) Source code where the main.py live
source.dir = .

# (list) Source files to include (let empty to include all the files)
source.include_exts = py,png,jpg,kv,atlas

# (list) List of inclusions using pattern matching
#source.include_patterns = assets/*,images/*.png

# (list) Source files to exclude (let empty to not exclude anything)
#source.exclude_exts = spec

# (list) List of directory to exclude (let empty to not exclude anything)
#source.exclude_dirs = tests, bin

# (list) List of exclusions using pattern matching
#source.exclude_patterns = license,images/*/*.jpg

# (str) Application versioning (method 1)
version = 0.1

# (str) Application versioning (method 2)
# version.regex = __version__ = \['"\](.*)['"]
# version.filename = %(source.dir)s/main.py

# (list) Application requirements
# comma separated e.g. requirements = sqlite3,kivy
requirements = python3,kivy

# (str) Custom source folders for requirements
# Sets custom source for any requirements with recipes
# requirements.source.kivy = ../../kivy

# (list) Garden requirements
#garden_requirements =

# (str) Presplash of the application
#presplash.filename = %(source.dir)s/data/presplash.png

# (str) Icon of the application
#icon.filename = %(source.dir)s/data/icon.png

# (str) Supported orientation (one of landscape, sensorLandscape, portrait or all)
orientation = portrait

# (list) List of service to declare
#services = NAME:ENTRYPOINT_TO_PY,NAME2:ENTRYPOINT2_TO_PY

#
# OSX Specific
#

#
# author = © Copyright Info

# change the major version of python used by the app
osx.python_version = 3

# Kivy version to use
osx.kivy_version = 1.9.1

#
# Android specific
#

# (bool) Indicate if the application should be fullscreen or not
fullscreen = 0

# (string) Presplash background color (for new android toolchain)
# Supported formats are: #RRGGBB #AARRGGBB or one of the following names:
# red, blue, green, black, white, gray, cyan, magenta, yellow, lightgray,
# darkgray, grey, lightgrey, darkgrey, aqua, fuchsia, lime, maroon, navy,
# olive, purple, silver, teal.
#android.presplash_color = #FFFFFF

# (list) Permissions
#android.permissions = INTERNET

# (int) Target Android API, should be as high as possible.
#android.api = 27

# (int) Minimum API your APK will support.
#android.minapi = 21

# (int) Android SDK version to use
#android.sdk = 20

# (str) Android NDK version to use
#android.ndk = 19b

# (int) Android NDK API to use. This is the minimum API your app will support, it should usually match android.minapi.
#android.ndk_api = 21

# (bool) Use --private data storage (True) or --dir public storage (False)
#android.private_storage = True

# (str) Android NDK directory (if empty, it will be automatically downloaded.)
#android.ndk_path =

# (str) Android SDK directory (if empty, it will be automatically downloaded.)
#android.sdk_path =

# (str) ANT directory (if empty, it will be automatically downloaded.)
#android.ant_path =

# (bool) If True, then skip trying to update the Android sdk
# This can be useful to avoid excess Internet downloads or save time
# when an update is due and you just want to test/build your package
# android.skip_update = False

# (bool) If True, then automatically accept SDK license
# agreements. This is intended for automation only. If set to False,
# the default, you will be shown the license when first running
# buildozer.
# android.accept_sdk_license = False

# (str) Android entry point, default is ok for Kivy-based app
#android.entrypoint = org.renpy.android.PythonActivity

# (str) Android app theme, default is ok for Kivy-based app
# android.apptheme = "@android:style/Theme.NoTitleBar"

# (list) Pattern to whitelist for the whole project
#android.whitelist =

# (str) Path to a custom whitelist file
#android.whitelist_src =

# (str) Path to a custom blacklist file
#android.blacklist_src =

# (list) List of Java .jar files to add to the libs so that pyjnius can access
# their classes. Don't add jars that you do not need, since extra jars can slow
# down the build process. Allows wildcards matching, for example:
# OUYA-ODK/libs/*.jar
#android.add_jars = foo.jar,bar.jar,path/to/more/*.jar

# (list) List of Java files to add to the android project (can be java or a
# directory containing the files)
#android.add_src =

# (list) Android AAR archives to add (currently works only with sdl2_gradle
# bootstrap)
#android.add_aars =

# (list) Gradle dependencies to add (currently works only with sdl2_gradle
# bootstrap)
#android.gradle_dependencies =

# (list) add java compile options
# this can for example be necessary when importing certain java libraries using the 'android.gradle_dependencies' option
# see https://developer.android.com/studio/write/java8-support for further information
# android.add_compile_options = "sourceCompatibility = 1.8", "targetCompatibility = 1.8"

# (list) Gradle repositories to add {can be necessary for some android.gradle_dependencies}
# please enclose in double quotes 
# e.g. android.gradle_repositories = "maven { url 'https://kotlin.bintray.com/ktor' }"
#android.add_gradle_repositories =

# (list) packaging options to add 
# see https://google.github.io/android-gradle-dsl/current/com.android.build.gradle.internal.dsl.PackagingOptions.html
# can be necessary to solve conflicts in gradle_dependencies
# please enclose in double quotes 
# e.g. android.add_packaging_options = "exclude 'META-INF/common.kotlin_module'", "exclude 'META-INF/*.kotlin_module'"
#android.add_gradle_repositories =

# (list) Java classes to add as activities to the manifest.
#android.add_activities = com.example.ExampleActivity

# (str) OUYA Console category. Should be one of GAME or APP
# If you leave this blank, OUYA support will not be enabled
#android.ouya.category = GAME

# (str) Filename of OUYA Console icon. It must be a 732x412 png image.
#android.ouya.icon.filename = %(source.dir)s/data/ouya_icon.png

# (str) XML file to include as an intent filters in <activity> tag
#android.manifest.intent_filters =

# (str) launchMode to set for the main activity
#android.manifest.launch_mode = standard

# (list) Android additional libraries to copy into libs/armeabi
#android.add_libs_armeabi = libs/android/*.so
#android.add_libs_armeabi_v7a = libs/android-v7/*.so
#android.add_libs_arm64_v8a = libs/android-v8/*.so
#android.add_libs_x86 = libs/android-x86/*.so
#android.add_libs_mips = libs/android-mips/*.so

# (bool) Indicate whether the screen should stay on
# Don't forget to add the WAKE_LOCK permission if you set this to True
#android.wakelock = False

# (list) Android application meta-data to set (key=value format)
#android.meta_data =

# (list) Android library project to add (will be added in the
# project.properties automatically.)
#android.library_references =

# (list) Android shared libraries which will be added to AndroidManifest.xml using <uses-library> tag
#android.uses_library =

# (str) Android logcat filters to use
#android.logcat_filters = *:S python:D

# (bool) Copy library instead of making a libpymodules.so
#android.copy_libs = 1

# (str) The Android arch to build for, choices: armeabi-v7a, arm64-v8a, x86, x86_64
android.arch = armeabi-v7a

# (int) overrides automatic versionCode computation (used in build.gradle)
# this is not the same as app version and should only be edited if you know what you're doing
# android.numeric_version = 1

#
# Python for android (p4a) specific
#

# (str) python-for-android fork to use, defaults to upstream (kivy)
#p4a.fork = kivy

# (str) python-for-android branch to use, defaults to master
#p4a.branch = master

# (str) python-for-android git clone directory (if empty, it will be automatically cloned from github)
#p4a.source_dir =

# (str) The directory in which python-for-android should look for your own build recipes (if any)
#p4a.local_recipes =

# (str) Filename to the hook for p4a
#p4a.hook =

# (str) Bootstrap to use for android builds
# p4a.bootstrap = sdl2

# (int) port number to specify an explicit --port= p4a argument (eg for bootstrap flask)
#p4a.port =


#
# iOS specific
#

# (str) Path to a custom kivy-ios folder
#ios.kivy_ios_dir = ../kivy-ios
# Alternately, specify the URL and branch of a git checkout:
ios.kivy_ios_url = https://github.com/kivy/kivy-ios
ios.kivy_ios_branch = master

# Another platform dependency: ios-deploy
# Uncomment to use a custom checkout
#ios.ios_deploy_dir = ../ios_deploy
# Or specify URL and branch
ios.ios_deploy_url = https://github.com/phonegap/ios-deploy
ios.ios_deploy_branch = 1.7.0

# (str) Name of the certificate to use for signing the debug version
# Get a list of available identities: buildozer ios list_identities
#ios.codesign.debug = "iPhone Developer: <lastname> <firstname> (<hexstring>)"

# (str) Name of the certificate to use for signing the release version
#ios.codesign.release = %(ios.codesign.debug)s


[buildozer]

# (int) Log level (0 = error only, 1 = info, 2 = debug (with command output))
log_level = 2

# (int) Display warning if buildozer is run as root (0 = False, 1 = True)
warn_on_root = 1

# (str) Path to build artifact storage, absolute or relative to spec file
# build_dir = ./.buildozer

# (str) Path to build output (i.e. .apk, .ipa) storage
# bin_dir = ./bin

#    -----------------------------------------------------------------------------
#    List as sections
#
#    You can define all the "list" as [section:key].
#    Each line will be considered as a option to the list.
#    Let's take [app] / source.exclude_patterns.
#    Instead of doing:
#
#[app]
#source.exclude_patterns = license,data/audio/*.wav,data/images/original/*
#
#    This can be translated into:
#
#[app:source.exclude_patterns]
#license
#data/audio/*.wav
#data/images/original/*
#


#    -----------------------------------------------------------------------------
#    Profiles
#
#    You can extend section / key with a profile
#    For example, you want to deploy a demo version of your application without
#    HD content. You could first change the title to add "(demo)" in the name
#    and extend the excluded directories to remove the HD content.
#
#[app@demo]
#title = My Application (demo)
#
#[app:source.exclude_patterns@demo]
#images/hd/*
#
#    Then, invoke the command line with the "demo" profile:
#
#buildozer --profile demo android debug

Si desea especificar cosas como el ícono, los requisitos, la pantalla de carga, etc., debe editar este archivo. Después de realizar todas las ediciones deseadas en su aplicación, ejecute buildozer -v android debugdesde el directorio de su aplicación para construir y compilar su aplicación. Esto puede llevar un tiempo, especialmente si tiene una máquina lenta.

Una vez finalizado el proceso, su terminal debería tener algunos registros, uno que confirme que la compilación fue exitosa:

Construcción exitosa de Android

También debe tener una versión APK de su aplicación en su directorio bin. Este es el ejecutable de la aplicación que instalará y ejecutará en su teléfono:

Android .apk en el directorio bin

Conclusión

¡Felicidades! Si ha seguido este tutorial paso a paso, debería tener una aplicación simple de generador de números aleatorios en su teléfono. Juega con él y ajusta algunos valores, luego reconstruye. Ejecutar la reconstrucción no llevará tanto tiempo como la primera compilación.

Como puede ver, crear una aplicación móvil con Python es bastante sencillo , siempre que esté familiarizado con el marco o módulo con el que está trabajando. Independientemente, la lógica se ejecuta de la misma manera.

Familiarícese con el módulo Kivy y sus widgets. Nunca se puede saber todo a la vez. Solo necesita encontrar un proyecto y mojarse los pies lo antes posible. Codificación feliz.

Enlace: https://blog.logrocket.com/build-android-application-kivy-python-framework/

#python 

KivyPythonフレームワークを使用してAndroidアプリケーションを構築する

あなたがモバイル開発を始めることを考えているPython開発者なら、Kivyフレームワークが最善の策です。Kivyを使用すると、iOS、Android、Windows、macOS、およびLinux用にコンパイルされるプラットフォームに依存しないアプリケーションを開発できます。この記事では、Androidが最も使用されているため、特にAndroidについて説明します。

簡単な乱数ジェネレーターアプリを作成します。このアプリを携帯電話にインストールして、完了したらテストできます。この記事を続けるには、Pythonに精通している必要があります。始めましょう！

Kivyを使い始める

まず、アプリ用の新しいディレクトリが必要になります。マシンにPythonがインストールされていることを確認し、新しいPythonファイルを開きます。以下のコマンドのいずれかを使用して、ターミナルからKivyモジュールをインストールする必要があります。パッケージの競合を避けるために、Kivyを仮想環境にインストールしていることを確認してください。

pip install kivy 
//
pip3 install kivy 

Kivyをインストールすると、以下のスクリーンショットのような成功メッセージがターミナルから表示されます。

がっかりしたインストール

Kivyのインストールに成功

 

次に、プロジェクトフォルダに移動します。このmain.pyファイルで、Kivyモジュールをインポートし、必要なバージョンを指定する必要があります。Kivy v2.0.0を使用できますが、Android 8.0より古いスマートフォンを使用している場合は、Kivyv1.9.0を使用することをお勧めします。ビルド中にさまざまなバージョンをいじって、機能とパフォーマンスの違いを確認できます。

import kivy次のように、行の直後にバージョン番号を追加します。

kivy.require('1.9.0')

次に、基本的にアプリを定義するクラスを作成します。私の名前を付けますRandomNumber。このクラスはappKivyからクラスを継承します。したがって、次appを追加してインポートする必要がありますfrom kivy.app import App。

class RandomNumber(App): 

ではRandomNumberクラスは、呼び出された関数を追加する必要がありますbuildとり、selfパラメータを。実際にUIを返すには、このbuild関数を使用します。今のところ、単純なラベルとして返送しています。そのためには、次Labelの行を使用してインポートする必要がありますfrom kivy.uix.label import Label。

import kivy
from kivy.app import App
from kivy.uix.label import Label

class RandomNumber(App):
  def build(self):
    return Label(text="Random Number Generator")

これで、アプリのスケルトンが完成しました。先に進む前に、RandomNumberクラスのインスタンスを作成し、ターミナルまたはIDEで実行して、インターフェイスを確認する必要があります。

import kivy from kivy.app import App from kivy.uix.label import Label class RandomNumber（App）：def build（self）：return Label（text = "Random Number Generator"）randomApp = RandomNumber（）randomApp.run（）

テキストを使用してクラスインスタンスを実行すると、Random Number Generator次のスクリーンショットのような単純なインターフェイスまたはウィンドウが表示されます。

 

コードを実行した後のシンプルなインターフェイス

すべての構築が完了するまで、Androidでテキストを実行することはできません。

インターフェースのアウトソーシング

次に、インターフェースをアウトソーシングする方法が必要になります。まず、ディレクトリにKivyファイルを作成します。このファイルには、ほとんどの設計作業が含まれています。このファイルには、小文字と.kv拡張子を使用して、クラスと同じ名前を付けることができます。Kivyはクラス名とファイル名を自動的に関連付けますが、それらがまったく同じである場合、Androidでは機能しない可能性があります。

その.kvファイル内で、ラベル、ボタン、フォームなどの要素を含むアプリのレイアウトを指定する必要があります。このデモを簡単にするために、タイトルRandom Numberのラベル、プレースホルダーとして機能するラベルを追加します。生成される乱数_、および関数Generateを呼び出すボタンgenerate。

私の.kvファイルは以下のコードのように見えますが、要件に合わせてさまざまな値をいじることができます。

<boxLayout>:
    orientation: "vertical"
    Label:
        text: "Random Number"
        font_size: 30
        color: 0, 0.62, 0.96

    Label:
        text: "_"
        font_size: 30

    Button:
        text: "Generate"
        font_size: 15 

このmain.pyファイルではLabel、KivyファイルがUIを処理するため、importステートメントは不要になりました。ただし、boxlayoutKivyファイルで使用するをインポートする必要があります。

メインファイルで、importステートメントを追加し、main.pyファイルを編集return BoxLayout()してbuildメソッドで読み取る必要があります。

from kivy.uix.boxlayout import BoxLayout

上記のコマンドを実行すると、乱数のタイトル、_プレースホルダー、およびクリック可能なgenerateボタンを備えたシンプルなインターフェイスが表示されます。

レンダリングされた乱数アプリ

Kivyファイルを機能させるために何もインポートする必要がなかったことに注意してください。基本的に、アプリを実行するboxlayoutと、クラスと同じ名前のKivyファイル内のファイルを検索して戻ります。これはシンプルなインターフェースであり、アプリを必要に応じて堅牢にすることができます。Kv言語のドキュメントを必ず確認してください。

乱数関数を生成する

アプリがほぼ完成したので、ユーザーがgenerateボタンをクリックしたときに乱数を生成し、その乱数をアプリのインターフェイスにレンダリングする簡単な関数が必要になります。そのためには、ファイル内のいくつかの変更を行う必要があります。

まず、で乱数を生成するために使用するモジュールをインポートしますimport random。次に、生成された番号を呼び出す関数またはメソッドを作成します。このデモでは、私は間の範囲を使用します0と2000。このrandom.randint(0, 2000)コマンドを使用すると、乱数を簡単に生成できます。これをすぐにコードに追加します。

次に、独自のバージョンとなる別のクラスを作成しますbox layout。このbox layoutクラスは、乱数を生成してインターフェイス上でレンダリングするメソッドを含むクラスを継承する必要があります。

class MyRoot(BoxLayout):
    def __init__(self):
        super(MyRoot, self).__init__()

そのクラス内で、generate乱数を生成するだけでなく、Kivyファイルに乱数として表示されるものを制御するラベルを操作するメソッドを作成します。

この方法に対応するには、最初に.kvファイルに変更を加える必要があります。以来MyRootクラスが継承しているbox layout、あなたが作ることができるMyRootあなたのトップレベルの要素.kvファイルを：

<MyRoot>:
    BoxLayout:
        orientation: "vertical"
        Label:
            text: "Random Number"
            font_size: 30
            color: 0, 0.62, 0.96

        Label:
            text: "_"
            font_size: 30

        Button:
            text: "Generate"
            font_size: 15

でインデントされたすべてのUI仕様を保持していることに注意してくださいBox Layout。この後、生成された番号を保持するIDをラベルに追加して、generate関数が呼び出されたときに簡単に操作できるようにする必要があります。このファイルのIDと、上部のメインコードの別のIDとの関係を、次のBoxLayout行の直前に指定する必要があります。

<MyRoot>:
    random_label: random_label
    BoxLayout:
        orientation: "vertical"
        Label:
            text: "Random Number"
            font_size: 30
            color: 0, 0.62, 0.96

        Label:
            id: random_label
            text: "_"
            font_size: 30

        Button:
            text: "Generate"
            font_size: 15

このrandom_label: random_label行は基本的に、IDrandom_labelを持つラベルがファイルrandom_label内にマップされることをmain.py意味します。つまり、操作random_labelするアクションはすべて、指定された名前のラベルにマップされます。

これで、メインファイルに乱数を生成するメソッドを作成できます。

def generate_number(self):
    self.random_label.text = str(random.randint(0, 2000))

# notice how the class method manipulates the text attributre of the random label by a# ssigning it a new random number generate by the 'random.randint(0, 2000)' funcion. S# ince this the random number generated is an integer, typecasting is required to make # it a string otherwise you will get a typeError in your terminal when you run it.

MyRootこのクラスは、以下のコードのようになります。

class MyRoot(BoxLayout):
    def __init__(self):
        super(MyRoot, self).__init__()

    def generate_number(self):
        self.random_label.text = str(random.randint(0, 2000))

おめでとう！これで、アプリのメインファイルが完成しました。あとは、generateボタンがクリックされたときに必ずこの関数を呼び出すようにしてください。ファイルのon_press: root.generate_number()ボタン選択部分に行を追加するだけで済み.kvます。

<MyRoot>:
    random_label: random_label
    BoxLayout:
        orientation: "vertical"
        Label:
            text: "Random Number"
            font_size: 30
            color: 0, 0.62, 0.96

        Label:
            id: random_label
            text: "_"
            font_size: 30

        Button:
            text: "Generate"
            font_size: 15
            on_press: root.generate_number()

これで、アプリを実行できます。

Androidでアプリをコンパイルする

Androidでアプリをコンパイルする前に、Windowsユーザーにとって悪いニュースがあります。Androidアプリケーションをコンパイルするには、LinuxまたはmacOSが必要です。ただし、個別のLinuxディストリビューションを用意する必要はなく、代わりに仮想マシンを使用できます。

完全なAndroid.apkアプリケーションをコンパイルして生成するには、Buildozerというツールを使用します。以下のコマンドのいずれかを使用して、ターミナルからBuildozerをインストールしましょう。

pip3 install buildozer
//
pip install buildozer

次に、Buildozerに必要な依存関係のいくつかをインストールします。私はLinuxErgoを使用しているので、Linux固有のコマンドを使用します。これらのコマンドを1つずつ実行する必要があります。

sudo apt update
sudo apt install -y git zip unzip openjdk-13-jdk python3-pip autoconf libtool pkg-config zlib1g-dev libncurses5-dev libncursesw5-dev libtinfo5 cmake libffi-dev libssl-dev

pip3 install --upgrade Cython==0.29.19 virtualenv 

# add the following line at the end of your ~/.bashrc file
export PATH=$PATH:~/.local/bin/

特定のコマンドを実行した後、を実行しbuildozer initます。以下のスクリーンショットのような出力が表示されます。

Buildozerの初期化が成功しました

上記のコマンドはBuildozer.specファイルを作成します。このファイルを使用して、アプリの名前やアイコンなどをアプリに指定.specできます。ファイルは次のコードブロックのようになります。

[app]

# (str) Title of your application
title = My Application

# (str) Package name
package.name = myapp

# (str) Package domain (needed for android/ios packaging)
package.domain = org.test

# (str) Source code where the main.py live
source.dir = .

# (list) Source files to include (let empty to include all the files)
source.include_exts = py,png,jpg,kv,atlas

# (list) List of inclusions using pattern matching
#source.include_patterns = assets/*,images/*.png

# (list) Source files to exclude (let empty to not exclude anything)
#source.exclude_exts = spec

# (list) List of directory to exclude (let empty to not exclude anything)
#source.exclude_dirs = tests, bin

# (list) List of exclusions using pattern matching
#source.exclude_patterns = license,images/*/*.jpg

# (str) Application versioning (method 1)
version = 0.1

# (str) Application versioning (method 2)
# version.regex = __version__ = \['"\](.*)['"]
# version.filename = %(source.dir)s/main.py

# (list) Application requirements
# comma separated e.g. requirements = sqlite3,kivy
requirements = python3,kivy

# (str) Custom source folders for requirements
# Sets custom source for any requirements with recipes
# requirements.source.kivy = ../../kivy

# (list) Garden requirements
#garden_requirements =

# (str) Presplash of the application
#presplash.filename = %(source.dir)s/data/presplash.png

# (str) Icon of the application
#icon.filename = %(source.dir)s/data/icon.png

# (str) Supported orientation (one of landscape, sensorLandscape, portrait or all)
orientation = portrait

# (list) List of service to declare
#services = NAME:ENTRYPOINT_TO_PY,NAME2:ENTRYPOINT2_TO_PY

#
# OSX Specific
#

#
# author = © Copyright Info

# change the major version of python used by the app
osx.python_version = 3

# Kivy version to use
osx.kivy_version = 1.9.1

#
# Android specific
#

# (bool) Indicate if the application should be fullscreen or not
fullscreen = 0

# (string) Presplash background color (for new android toolchain)
# Supported formats are: #RRGGBB #AARRGGBB or one of the following names:
# red, blue, green, black, white, gray, cyan, magenta, yellow, lightgray,
# darkgray, grey, lightgrey, darkgrey, aqua, fuchsia, lime, maroon, navy,
# olive, purple, silver, teal.
#android.presplash_color = #FFFFFF

# (list) Permissions
#android.permissions = INTERNET

# (int) Target Android API, should be as high as possible.
#android.api = 27

# (int) Minimum API your APK will support.
#android.minapi = 21

# (int) Android SDK version to use
#android.sdk = 20

# (str) Android NDK version to use
#android.ndk = 19b

# (int) Android NDK API to use. This is the minimum API your app will support, it should usually match android.minapi.
#android.ndk_api = 21

# (bool) Use --private data storage (True) or --dir public storage (False)
#android.private_storage = True

# (str) Android NDK directory (if empty, it will be automatically downloaded.)
#android.ndk_path =

# (str) Android SDK directory (if empty, it will be automatically downloaded.)
#android.sdk_path =

# (str) ANT directory (if empty, it will be automatically downloaded.)
#android.ant_path =

# (bool) If True, then skip trying to update the Android sdk
# This can be useful to avoid excess Internet downloads or save time
# when an update is due and you just want to test/build your package
# android.skip_update = False

# (bool) If True, then automatically accept SDK license
# agreements. This is intended for automation only. If set to False,
# the default, you will be shown the license when first running
# buildozer.
# android.accept_sdk_license = False

# (str) Android entry point, default is ok for Kivy-based app
#android.entrypoint = org.renpy.android.PythonActivity

# (str) Android app theme, default is ok for Kivy-based app
# android.apptheme = "@android:style/Theme.NoTitleBar"

# (list) Pattern to whitelist for the whole project
#android.whitelist =

# (str) Path to a custom whitelist file
#android.whitelist_src =

# (str) Path to a custom blacklist file
#android.blacklist_src =

# (list) List of Java .jar files to add to the libs so that pyjnius can access
# their classes. Don't add jars that you do not need, since extra jars can slow
# down the build process. Allows wildcards matching, for example:
# OUYA-ODK/libs/*.jar
#android.add_jars = foo.jar,bar.jar,path/to/more/*.jar

# (list) List of Java files to add to the android project (can be java or a
# directory containing the files)
#android.add_src =

# (list) Android AAR archives to add (currently works only with sdl2_gradle
# bootstrap)
#android.add_aars =

# (list) Gradle dependencies to add (currently works only with sdl2_gradle
# bootstrap)
#android.gradle_dependencies =

# (list) add java compile options
# this can for example be necessary when importing certain java libraries using the 'android.gradle_dependencies' option
# see https://developer.android.com/studio/write/java8-support for further information
# android.add_compile_options = "sourceCompatibility = 1.8", "targetCompatibility = 1.8"

# (list) Gradle repositories to add {can be necessary for some android.gradle_dependencies}
# please enclose in double quotes 
# e.g. android.gradle_repositories = "maven { url 'https://kotlin.bintray.com/ktor' }"
#android.add_gradle_repositories =

# (list) packaging options to add 
# see https://google.github.io/android-gradle-dsl/current/com.android.build.gradle.internal.dsl.PackagingOptions.html
# can be necessary to solve conflicts in gradle_dependencies
# please enclose in double quotes 
# e.g. android.add_packaging_options = "exclude 'META-INF/common.kotlin_module'", "exclude 'META-INF/*.kotlin_module'"
#android.add_gradle_repositories =

# (list) Java classes to add as activities to the manifest.
#android.add_activities = com.example.ExampleActivity

# (str) OUYA Console category. Should be one of GAME or APP
# If you leave this blank, OUYA support will not be enabled
#android.ouya.category = GAME

# (str) Filename of OUYA Console icon. It must be a 732x412 png image.
#android.ouya.icon.filename = %(source.dir)s/data/ouya_icon.png

# (str) XML file to include as an intent filters in <activity> tag
#android.manifest.intent_filters =

# (str) launchMode to set for the main activity
#android.manifest.launch_mode = standard

# (list) Android additional libraries to copy into libs/armeabi
#android.add_libs_armeabi = libs/android/*.so
#android.add_libs_armeabi_v7a = libs/android-v7/*.so
#android.add_libs_arm64_v8a = libs/android-v8/*.so
#android.add_libs_x86 = libs/android-x86/*.so
#android.add_libs_mips = libs/android-mips/*.so

# (bool) Indicate whether the screen should stay on
# Don't forget to add the WAKE_LOCK permission if you set this to True
#android.wakelock = False

# (list) Android application meta-data to set (key=value format)
#android.meta_data =

# (list) Android library project to add (will be added in the
# project.properties automatically.)
#android.library_references =

# (list) Android shared libraries which will be added to AndroidManifest.xml using <uses-library> tag
#android.uses_library =

# (str) Android logcat filters to use
#android.logcat_filters = *:S python:D

# (bool) Copy library instead of making a libpymodules.so
#android.copy_libs = 1

# (str) The Android arch to build for, choices: armeabi-v7a, arm64-v8a, x86, x86_64
android.arch = armeabi-v7a

# (int) overrides automatic versionCode computation (used in build.gradle)
# this is not the same as app version and should only be edited if you know what you're doing
# android.numeric_version = 1

#
# Python for android (p4a) specific
#

# (str) python-for-android fork to use, defaults to upstream (kivy)
#p4a.fork = kivy

# (str) python-for-android branch to use, defaults to master
#p4a.branch = master

# (str) python-for-android git clone directory (if empty, it will be automatically cloned from github)
#p4a.source_dir =

# (str) The directory in which python-for-android should look for your own build recipes (if any)
#p4a.local_recipes =

# (str) Filename to the hook for p4a
#p4a.hook =

# (str) Bootstrap to use for android builds
# p4a.bootstrap = sdl2

# (int) port number to specify an explicit --port= p4a argument (eg for bootstrap flask)
#p4a.port =


#
# iOS specific
#

# (str) Path to a custom kivy-ios folder
#ios.kivy_ios_dir = ../kivy-ios
# Alternately, specify the URL and branch of a git checkout:
ios.kivy_ios_url = https://github.com/kivy/kivy-ios
ios.kivy_ios_branch = master

# Another platform dependency: ios-deploy
# Uncomment to use a custom checkout
#ios.ios_deploy_dir = ../ios_deploy
# Or specify URL and branch
ios.ios_deploy_url = https://github.com/phonegap/ios-deploy
ios.ios_deploy_branch = 1.7.0

# (str) Name of the certificate to use for signing the debug version
# Get a list of available identities: buildozer ios list_identities
#ios.codesign.debug = "iPhone Developer: <lastname> <firstname> (<hexstring>)"

# (str) Name of the certificate to use for signing the release version
#ios.codesign.release = %(ios.codesign.debug)s


[buildozer]

# (int) Log level (0 = error only, 1 = info, 2 = debug (with command output))
log_level = 2

# (int) Display warning if buildozer is run as root (0 = False, 1 = True)
warn_on_root = 1

# (str) Path to build artifact storage, absolute or relative to spec file
# build_dir = ./.buildozer

# (str) Path to build output (i.e. .apk, .ipa) storage
# bin_dir = ./bin

#    -----------------------------------------------------------------------------
#    List as sections
#
#    You can define all the "list" as [section:key].
#    Each line will be considered as a option to the list.
#    Let's take [app] / source.exclude_patterns.
#    Instead of doing:
#
#[app]
#source.exclude_patterns = license,data/audio/*.wav,data/images/original/*
#
#    This can be translated into:
#
#[app:source.exclude_patterns]
#license
#data/audio/*.wav
#data/images/original/*
#


#    -----------------------------------------------------------------------------
#    Profiles
#
#    You can extend section / key with a profile
#    For example, you want to deploy a demo version of your application without
#    HD content. You could first change the title to add "(demo)" in the name
#    and extend the excluded directories to remove the HD content.
#
#[app@demo]
#title = My Application (demo)
#
#[app:source.exclude_patterns@demo]
#images/hd/*
#
#    Then, invoke the command line with the "demo" profile:
#
#buildozer --profile demo android debug

アイコン、要件、ロード画面などを指定する場合は、このファイルを編集する必要があります。アプリケーションに必要なすべての編集を行った後buildozer -v android debug、アプリディレクトリから実行して、アプリケーションをビルドおよびコンパイルします。特に低速のマシンを使用している場合は、これに時間がかかることがあります。

プロセスが完了すると、端末にいくつかのログが表示され、ビルドが成功したことを確認できます。

Androidの成功したビルド

また、binディレクトリにアプリのAPKバージョンが必要です。これは、携帯電話にインストールして実行するアプリケーションの実行可能ファイルです。

binディレクトリのAndroid.apk

結論

おめでとう！このチュートリアルをステップバイステップで実行した場合は、電話に単純な乱数ジェネレーターアプリがインストールされているはずです。それをいじって、いくつかの値を微調整してから、再構築してください。再構築の実行は、最初のビルドほど時間はかかりません。

ご覧のとおり、Pythonを使用したモバイルアプリケーションの構築は、使用しているフレームワークまたはモジュールに精通している限り、かなり簡単です。とにかく、ロジックは同じ方法で実行されます。

Kivyモジュールとそのウィジェットに慣れてください。すべてを一度に知ることはできません。プロジェクトを見つけて、できるだけ早く足を濡らすだけです。ハッピーコーディング。

リンク：https：//blog.logrocket.com/build-android-application-kivy-python-framework/

#python 

EasyMDE: Simple, Beautiful and Embeddable JavaScript Markdown Editor

EasyMDE - Markdown Editor 

This repository is a fork of SimpleMDE, made by Sparksuite. Go to the dedicated section for more information.

A drop-in JavaScript text area replacement for writing beautiful and understandable Markdown. EasyMDE allows users who may be less experienced with Markdown to use familiar toolbar buttons and shortcuts.

In addition, the syntax is rendered while editing to clearly show the expected result. Headings are larger, emphasized words are italicized, links are underlined, etc.

EasyMDE also features both built-in auto saving and spell checking. The editor is entirely customizable, from theming to toolbar buttons and javascript hooks.

Try the demo

Quick access

• EasyMDE - Markdown Editor
  • Quick access
  • Install EasyMDE
  • How to use
    • Loading the editor
    • Editor functions
  • Configuration
    • Options list
    • Options example
    • Toolbar icons
    • Toolbar customization
    • Keyboard shortcuts
  • Advanced use
    • Event handling
    • Removing EasyMDE from text area
    • Useful methods
  • How it works
  • SimpleMDE fork
  • Hacking EasyMDE
  • Contributing
  • License

Install EasyMDE

Via npm:

npm install easymde

Via the UNPKG CDN:

<link rel="stylesheet" href="https://unpkg.com/easymde/dist/easymde.min.css">
<script src="https://unpkg.com/easymde/dist/easymde.min.js"></script>

Or jsDelivr:

<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/easymde/dist/easymde.min.css">
<script src="https://cdn.jsdelivr.net/npm/easymde/dist/easymde.min.js"></script>

How to use

Loading the editor

After installing and/or importing the module, you can load EasyMDE onto the first textarea element on the web page:

<textarea></textarea>
<script>
const easyMDE = new EasyMDE();
</script>

Alternatively you can select a specific textarea, via JavaScript:

<textarea id="my-text-area"></textarea>
<script>
const easyMDE = new EasyMDE({element: document.getElementById('my-text-area')});
</script>

Editor functions

Use easyMDE.value() to get the content of the editor:

<script>
easyMDE.value();
</script>

Use easyMDE.value(val) to set the content of the editor:

<script>
easyMDE.value('New input for **EasyMDE**');
</script>

Configuration

Options list

• autoDownloadFontAwesome: If set to true, force downloads Font Awesome (used for icons). If set to false, prevents downloading. Defaults to undefined, which will intelligently check whether Font Awesome has already been included, then download accordingly.
• autofocus: If set to true, focuses the editor automatically. Defaults to false.
• autosave: Saves the text that's being written and will load it back in the future. It will forget the text when the form it's contained in is submitted.
  • enabled: If set to true, saves the text automatically. Defaults to false.
  • delay: Delay between saves, in milliseconds. Defaults to 10000 (10 seconds).
  • submit_delay: Delay before assuming that submit of the form failed and saving the text, in milliseconds. Defaults to autosave.delay or 10000 (10 seconds).
  • uniqueId: You must set a unique string identifier so that EasyMDE can autosave. Something that separates this from other instances of EasyMDE elsewhere on your website.
  • timeFormat: Set DateTimeFormat. More information see DateTimeFormat instances. Default locale: en-US, format: hour:minute.
  • text: Set text for autosave.
• autoRefresh: Useful, when initializing the editor in a hidden DOM node. If set to { delay: 300 }, it will check every 300 ms if the editor is visible and if positive, call CodeMirror's refresh().
• blockStyles: Customize how certain buttons that style blocks of text behave.
  • bold: Can be set to ** or __. Defaults to **.
  • code: Can be set to ``` or ~~~. Defaults to ```.
  • italic: Can be set to * or _. Defaults to *.
• unorderedListStyle: can be *, - or +. Defaults to *.
• scrollbarStyle: Chooses a scrollbar implementation. The default is "native", showing native scrollbars. The core library also provides the "null" style, which completely hides the scrollbars. Addons can implement additional scrollbar models.
• element: The DOM element for the textarea element to use. Defaults to the first textarea element on the page.
• forceSync: If set to true, force text changes made in EasyMDE to be immediately stored in original text area. Defaults to false.
• hideIcons: An array of icon names to hide. Can be used to hide specific icons shown by default without completely customizing the toolbar.
• indentWithTabs: If set to false, indent using spaces instead of tabs. Defaults to true.
• initialValue: If set, will customize the initial value of the editor.
• previewImagesInEditor: - EasyMDE will show preview of images, false by default, preview for images will appear only for images on separate lines.
• imagesPreviewHandler: - A custom function for handling the preview of images. Takes the parsed string between the parantheses of the image markdown ![]( ) as argument and returns a string that serves as the src attribute of the <img> tag in the preview. Enables dynamic previewing of images in the frontend without having to upload them to a server, allows copy-pasting of images to the editor with preview.
• insertTexts: Customize how certain buttons that insert text behave. Takes an array with two elements. The first element will be the text inserted before the cursor or highlight, and the second element will be inserted after. For example, this is the default link value: ["[", "](http://)"].
  • horizontalRule
  • image
  • link
  • table
• lineNumbers: If set to true, enables line numbers in the editor.
• lineWrapping: If set to false, disable line wrapping. Defaults to true.
• minHeight: Sets the minimum height for the composition area, before it starts auto-growing. Should be a string containing a valid CSS value like "500px". Defaults to "300px".
• maxHeight: Sets fixed height for the composition area. minHeight option will be ignored. Should be a string containing a valid CSS value like "500px". Defaults to undefined.
• onToggleFullScreen: A function that gets called when the editor's full screen mode is toggled. The function will be passed a boolean as parameter, true when the editor is currently going into full screen mode, or false.
• parsingConfig: Adjust settings for parsing the Markdown during editing (not previewing).
  • allowAtxHeaderWithoutSpace: If set to true, will render headers without a space after the #. Defaults to false.
  • strikethrough: If set to false, will not process GFM strikethrough syntax. Defaults to true.
  • underscoresBreakWords: If set to true, let underscores be a delimiter for separating words. Defaults to false.
• overlayMode: Pass a custom codemirror overlay mode to parse and style the Markdown during editing.
  • mode: A codemirror mode object.
  • combine: If set to false, will replace CSS classes returned by the default Markdown mode. Otherwise the classes returned by the custom mode will be combined with the classes returned by the default mode. Defaults to true.
• placeholder: If set, displays a custom placeholder message.
• previewClass: A string or array of strings that will be applied to the preview screen when activated. Defaults to "editor-preview".
• previewRender: Custom function for parsing the plaintext Markdown and returning HTML. Used when user previews.
• promptURLs: If set to true, a JS alert window appears asking for the link or image URL. Defaults to false.
• promptTexts: Customize the text used to prompt for URLs.
  • image: The text to use when prompting for an image's URL. Defaults to URL of the image:.
  • link: The text to use when prompting for a link's URL. Defaults to URL for the link:.
• uploadImage: If set to true, enables the image upload functionality, which can be triggered by drag and drop, copy-paste and through the browse-file window (opened when the user click on the upload-image icon). Defaults to false.
• imageMaxSize: Maximum image size in bytes, checked before upload (note: never trust client, always check the image size at server-side). Defaults to 1024 * 1024 * 2 (2 MB).
• imageAccept: A comma-separated list of mime-types used to check image type before upload (note: never trust client, always check file types at server-side). Defaults to image/png, image/jpeg.
• imageUploadFunction: A custom function for handling the image upload. Using this function will render the options imageMaxSize, imageAccept, imageUploadEndpoint and imageCSRFToken ineffective.
  • The function gets a file and onSuccess and onError callback functions as parameters. onSuccess(imageUrl: string) and onError(errorMessage: string)
• imageUploadEndpoint: The endpoint where the images data will be sent, via an asynchronous POST request. The server is supposed to save this image, and return a JSON response.
  • if the request was successfully processed (HTTP 200 OK): {"data": {"filePath": "<filePath>"}} where filePath is the path of the image (absolute if imagePathAbsolute is set to true, relative if otherwise);
  • otherwise: {"error": "<errorCode>"}, where errorCode can be noFileGiven (HTTP 400 Bad Request), typeNotAllowed (HTTP 415 Unsupported Media Type), fileTooLarge (HTTP 413 Payload Too Large) or importError (see errorMessages below). If errorCode is not one of the errorMessages, it is alerted unchanged to the user. This allows for server-side error messages. No default value.
• imagePathAbsolute: If set to true, will treat imageUrl from imageUploadFunction and filePath returned from imageUploadEndpoint as an absolute rather than relative path, i.e. not prepend window.location.origin to it.
• imageCSRFToken: CSRF token to include with AJAX call to upload image. For various instances like Django, Spring and Laravel.
• imageCSRFName: CSRF token filed name to include with AJAX call to upload image, applied when imageCSRFToken has value, defaults to csrfmiddlewaretoken.
• imageCSRFHeader: If set to true, passing CSRF token via header. Defaults to false, which pass CSRF through request body.
• imageTexts: Texts displayed to the user (mainly on the status bar) for the import image feature, where #image_name#, #image_size# and #image_max_size# will replaced by their respective values, that can be used for customization or internationalization:
  • sbInit: Status message displayed initially if uploadImage is set to true. Defaults to Attach files by drag and dropping or pasting from clipboard..
  • sbOnDragEnter: Status message displayed when the user drags a file to the text area. Defaults to Drop image to upload it..
  • sbOnDrop: Status message displayed when the user drops a file in the text area. Defaults to Uploading images #images_names#.
  • sbProgress: Status message displayed to show uploading progress. Defaults to Uploading #file_name#: #progress#%.
  • sbOnUploaded: Status message displayed when the image has been uploaded. Defaults to Uploaded #image_name#.
  • sizeUnits: A comma-separated list of units used to display messages with human-readable file sizes. Defaults to B, KB, MB (example: 218 KB). You can use B,KB,MB instead if you prefer without whitespaces (218KB).
• errorMessages: Errors displayed to the user, using the errorCallback option, where #image_name#, #image_size# and #image_max_size# will replaced by their respective values, that can be used for customization or internationalization:
  • noFileGiven: The server did not receive any file from the user. Defaults to You must select a file..
  • typeNotAllowed: The user send a file type which doesn't match the imageAccept list, or the server returned this error code. Defaults to This image type is not allowed..
  • fileTooLarge: The size of the image being imported is bigger than the imageMaxSize, or if the server returned this error code. Defaults to Image #image_name# is too big (#image_size#).\nMaximum file size is #image_max_size#..
  • importError: An unexpected error occurred when uploading the image. Defaults to Something went wrong when uploading the image #image_name#..
• errorCallback: A callback function used to define how to display an error message. Defaults to (errorMessage) => alert(errorMessage).
• renderingConfig: Adjust settings for parsing the Markdown during previewing (not editing).
  • codeSyntaxHighlighting: If set to true, will highlight using highlight.js. Defaults to false. To use this feature you must include highlight.js on your page or pass in using the hljs option. For example, include the script and the CSS files like:
    <script src="https://cdn.jsdelivr.net/highlight.js/latest/highlight.min.js"></script>
<link rel="stylesheet" href="https://cdn.jsdelivr.net/highlight.js/latest/styles/github.min.css">
  • hljs: An injectible instance of highlight.js. If you don't want to rely on the global namespace (window.hljs), you can provide an instance here. Defaults to undefined.
  • markedOptions: Set the internal Markdown renderer's options. Other renderingConfig options will take precedence.
  • singleLineBreaks: If set to false, disable parsing GitHub Flavored Markdown (GFM) single line breaks. Defaults to true.
  • sanitizerFunction: Custom function for sanitizing the HTML output of Markdown renderer.
• shortcuts: Keyboard shortcuts associated with this instance. Defaults to the array of shortcuts.
• showIcons: An array of icon names to show. Can be used to show specific icons hidden by default without completely customizing the toolbar.
• spellChecker: If set to false, disable the spell checker. Defaults to true. Optionally pass a CodeMirrorSpellChecker-compliant function.
• inputStyle: textarea or contenteditable. Defaults to textarea for desktop and contenteditable for mobile. contenteditable option is necessary to enable nativeSpellcheck.
• nativeSpellcheck: If set to false, disable native spell checker. Defaults to true.
• sideBySideFullscreen: If set to false, allows side-by-side editing without going into fullscreen. Defaults to true.
• status: If set to false, hide the status bar. Defaults to the array of built-in status bar items.
  • Optionally, you can set an array of status bar items to include, and in what order. You can even define your own custom status bar items.
• styleSelectedText: If set to false, remove the CodeMirror-selectedtext class from selected lines. Defaults to true.
• syncSideBySidePreviewScroll: If set to false, disable syncing scroll in side by side mode. Defaults to true.
• tabSize: If set, customize the tab size. Defaults to 2.
• theme: Override the theme. Defaults to easymde.
• toolbar: If set to false, hide the toolbar. Defaults to the array of icons.
• toolbarTips: If set to false, disable toolbar button tips. Defaults to true.
• direction: rtl or ltr. Changes text direction to support right-to-left languages. Defaults to ltr.

Options example

Most options demonstrate the non-default behavior:

const editor = new EasyMDE({
    autofocus: true,
    autosave: {
        enabled: true,
        uniqueId: "MyUniqueID",
        delay: 1000,
        submit_delay: 5000,
        timeFormat: {
            locale: 'en-US',
            format: {
                year: 'numeric',
                month: 'long',
                day: '2-digit',
                hour: '2-digit',
                minute: '2-digit',
            },
        },
        text: "Autosaved: "
    },
    blockStyles: {
        bold: "__",
        italic: "_",
    },
    unorderedListStyle: "-",
    element: document.getElementById("MyID"),
    forceSync: true,
    hideIcons: ["guide", "heading"],
    indentWithTabs: false,
    initialValue: "Hello world!",
    insertTexts: {
        horizontalRule: ["", "\n\n-----\n\n"],
        image: ["![](http://", ")"],
        link: ["[", "](https://)"],
        table: ["", "\n\n| Column 1 | Column 2 | Column 3 |\n| -------- | -------- | -------- |\n| Text     | Text      | Text     |\n\n"],
    },
    lineWrapping: false,
    minHeight: "500px",
    parsingConfig: {
        allowAtxHeaderWithoutSpace: true,
        strikethrough: false,
        underscoresBreakWords: true,
    },
    placeholder: "Type here...",

    previewClass: "my-custom-styling",
    previewClass: ["my-custom-styling", "more-custom-styling"],

    previewRender: (plainText) => customMarkdownParser(plainText), // Returns HTML from a custom parser
    previewRender: (plainText, preview) => { // Async method
        setTimeout(() => {
            preview.innerHTML = customMarkdownParser(plainText);
        }, 250);

        return "Loading...";
    },
    promptURLs: true,
    promptTexts: {
        image: "Custom prompt for URL:",
        link: "Custom prompt for URL:",
    },
    renderingConfig: {
        singleLineBreaks: false,
        codeSyntaxHighlighting: true,
        sanitizerFunction: (renderedHTML) => {
            // Using DOMPurify and only allowing <b> tags
            return DOMPurify.sanitize(renderedHTML, {ALLOWED_TAGS: ['b']})
        },
    },
    shortcuts: {
        drawTable: "Cmd-Alt-T"
    },
    showIcons: ["code", "table"],
    spellChecker: false,
    status: false,
    status: ["autosave", "lines", "words", "cursor"], // Optional usage
    status: ["autosave", "lines", "words", "cursor", {
        className: "keystrokes",
        defaultValue: (el) => {
            el.setAttribute('data-keystrokes', 0);
        },
        onUpdate: (el) => {
            const keystrokes = Number(el.getAttribute('data-keystrokes')) + 1;
            el.innerHTML = `${keystrokes} Keystrokes`;
            el.setAttribute('data-keystrokes', keystrokes);
        },
    }], // Another optional usage, with a custom status bar item that counts keystrokes
    styleSelectedText: false,
    sideBySideFullscreen: false,
    syncSideBySidePreviewScroll: false,
    tabSize: 4,
    toolbar: false,
    toolbarTips: false,
});

Toolbar icons

Below are the built-in toolbar icons (only some of which are enabled by default), which can be reorganized however you like. "Name" is the name of the icon, referenced in the JavaScript. "Action" is either a function or a URL to open. "Class" is the class given to the icon. "Tooltip" is the small tooltip that appears via the title="" attribute. Note that shortcut hints are added automatically and reflect the specified action if it has a key bind assigned to it (i.e. with the value of action set to bold and that of tooltip set to Bold, the final text the user will see would be "Bold (Ctrl-B)").

Additionally, you can add a separator between any icons by adding "|" to the toolbar array.

Name	Action	Tooltip Class
bold	toggleBold	Bold fa fa-bold
italic	toggleItalic	Italic fa fa-italic
strikethrough	toggleStrikethrough	Strikethrough fa fa-strikethrough
heading	toggleHeadingSmaller	Heading fa fa-header
heading-smaller	toggleHeadingSmaller	Smaller Heading fa fa-header
heading-bigger	toggleHeadingBigger	Bigger Heading fa fa-lg fa-header
heading-1	toggleHeading1	Big Heading fa fa-header header-1
heading-2	toggleHeading2	Medium Heading fa fa-header header-2
heading-3	toggleHeading3	Small Heading fa fa-header header-3
code	toggleCodeBlock	Code fa fa-code
quote	toggleBlockquote	Quote fa fa-quote-left
unordered-list	toggleUnorderedList	Generic List fa fa-list-ul
ordered-list	toggleOrderedList	Numbered List fa fa-list-ol
clean-block	cleanBlock	Clean block fa fa-eraser
link	drawLink	Create Link fa fa-link
image	drawImage	Insert Image fa fa-picture-o
table	drawTable	Insert Table fa fa-table
horizontal-rule	drawHorizontalRule	Insert Horizontal Line fa fa-minus
preview	togglePreview	Toggle Preview fa fa-eye no-disable
side-by-side	toggleSideBySide	Toggle Side by Side fa fa-columns no-disable no-mobile
fullscreen	toggleFullScreen	Toggle Fullscreen fa fa-arrows-alt no-disable no-mobile
guide	This link	Markdown Guide fa fa-question-circle
undo	undo	Undo fa fa-undo
redo	redo	Redo fa fa-redo

Toolbar customization

Customize the toolbar using the toolbar option.

Only the order of existing buttons:

const easyMDE = new EasyMDE({
    toolbar: ["bold", "italic", "heading", "|", "quote"]
});

All information and/or add your own icons

const easyMDE = new EasyMDE({
    toolbar: [
        {
            name: "bold",
            action: EasyMDE.toggleBold,
            className: "fa fa-bold",
            title: "Bold",
        },
        "italics", // shortcut to pre-made button
        {
            name: "custom",
            action: (editor) => {
                // Add your own code
            },
            className: "fa fa-star",
            title: "Custom Button",
            attributes: { // for custom attributes
                id: "custom-id",
                "data-value": "custom value" // HTML5 data-* attributes need to be enclosed in quotation marks ("") because of the dash (-) in its name.
            }
        },
        "|" // Separator
        // [, ...]
    ]
});

Put some buttons on dropdown menu

const easyMDE = new EasyMDE({
    toolbar: [{
                name: "heading",
                action: EasyMDE.toggleHeadingSmaller,
                className: "fa fa-header",
                title: "Headers",
            },
            "|",
            {
                name: "others",
                className: "fa fa-blind",
                title: "others buttons",
                children: [
                    {
                        name: "image",
                        action: EasyMDE.drawImage,
                        className: "fa fa-picture-o",
                        title: "Image",
                    },
                    {
                        name: "quote",
                        action: EasyMDE.toggleBlockquote,
                        className: "fa fa-percent",
                        title: "Quote",
                    },
                    {
                        name: "link",
                        action: EasyMDE.drawLink,
                        className: "fa fa-link",
                        title: "Link",
                    }
                ]
            },
        // [, ...]
    ]
});

Keyboard shortcuts

EasyMDE comes with an array of predefined keyboard shortcuts, but they can be altered with a configuration option. The list of default ones is as follows:

Shortcut (Windows / Linux)	Shortcut (macOS)	Action
Ctrl-'	Cmd-'	"toggleBlockquote"
Ctrl-B	Cmd-B	"toggleBold"
Ctrl-E	Cmd-E	"cleanBlock"
Ctrl-H	Cmd-H	"toggleHeadingSmaller"
Ctrl-I	Cmd-I	"toggleItalic"
Ctrl-K	Cmd-K	"drawLink"
Ctrl-L	Cmd-L	"toggleUnorderedList"
Ctrl-P	Cmd-P	"togglePreview"
Ctrl-Alt-C	Cmd-Alt-C	"toggleCodeBlock"
Ctrl-Alt-I	Cmd-Alt-I	"drawImage"
Ctrl-Alt-L	Cmd-Alt-L	"toggleOrderedList"
Shift-Ctrl-H	Shift-Cmd-H	"toggleHeadingBigger"
F9	F9	"toggleSideBySide"
F11	F11	"toggleFullScreen"

Here is how you can change a few, while leaving others untouched:

const editor = new EasyMDE({
    shortcuts: {
        "toggleOrderedList": "Ctrl-Alt-K", // alter the shortcut for toggleOrderedList
        "toggleCodeBlock": null, // unbind Ctrl-Alt-C
        "drawTable": "Cmd-Alt-T", // bind Cmd-Alt-T to drawTable action, which doesn't come with a default shortcut
    }
});

Shortcuts are automatically converted between platforms. If you define a shortcut as "Cmd-B", on PC that shortcut will be changed to "Ctrl-B". Conversely, a shortcut defined as "Ctrl-B" will become "Cmd-B" for Mac users.

The list of actions that can be bound is the same as the list of built-in actions available for toolbar buttons.

Advanced use

Event handling

You can catch the following list of events: https://codemirror.net/doc/manual.html#events

const easyMDE = new EasyMDE();
easyMDE.codemirror.on("change", () => {
    console.log(easyMDE.value());
});

Removing EasyMDE from text area

You can revert to the initial text area by calling the toTextArea method. Note that this clears up the autosave (if enabled) associated with it. The text area will retain any text from the destroyed EasyMDE instance.

const easyMDE = new EasyMDE();
// ...
easyMDE.toTextArea();
easyMDE = null;

If you need to remove registered event listeners (when the editor is not needed anymore), call easyMDE.cleanup().

Useful methods

The following self-explanatory methods may be of use while developing with EasyMDE.

const easyMDE = new EasyMDE();
easyMDE.isPreviewActive(); // returns boolean
easyMDE.isSideBySideActive(); // returns boolean
easyMDE.isFullscreenActive(); // returns boolean
easyMDE.clearAutosavedValue(); // no returned value

How it works

EasyMDE is a continuation of SimpleMDE.

SimpleMDE began as an improvement of lepture's Editor project, but has now taken on an identity of its own. It is bundled with CodeMirror and depends on Font Awesome.

CodeMirror is the backbone of the project and parses much of the Markdown syntax as it's being written. This allows us to add styles to the Markdown that's being written. Additionally, a toolbar and status bar have been added to the top and bottom, respectively. Previews are rendered by Marked using GitHub Flavored Markdown (GFM).

SimpleMDE fork

I originally made this fork to implement FontAwesome 5 compatibility into SimpleMDE. When that was done I submitted a pull request, which has not been accepted yet. This, and the project being inactive since May 2017, triggered me to make more changes and try to put new life into the project.

Changes include:

• FontAwesome 5 compatibility
• Guide button works when editor is in preview mode
• Links are now https:// by default
• Small styling changes
• Support for Node 8 and beyond
• Lots of refactored code
• Links in preview will open in a new tab by default
• TypeScript support

My intention is to continue development on this project, improving it and keeping it alive.

Hacking EasyMDE

You may want to edit this library to adapt its behavior to your needs. This can be done in some quick steps:

1. Follow the prerequisites and installation instructions in the contribution guide;
2. Do your changes;
3. Run gulp command, which will generate files: dist/easymde.min.css and dist/easymde.min.js;
4. Copy-paste those files to your code base, and you are done.

Contributing

Want to contribute to EasyMDE? Thank you! We have a contribution guide just for you!

---

Author: Ionaru
Source Code: https://github.com/Ionaru/easy-markdown-editor
License: MIT license

#react-native #react 

Dotnet Script: Run C# Scripts From The .NET CLI

dotnet script

Run C# scripts from the .NET CLI, define NuGet packages inline and edit/debug them in VS Code - all of that with full language services support from OmniSharp.

NuGet Packages

Name	Version	Framework(s)
dotnet-script (global tool)		net6.0, net5.0, netcoreapp3.1
Dotnet.Script (CLI as Nuget)		net6.0, net5.0, netcoreapp3.1
Dotnet.Script.Core		netcoreapp3.1 , netstandard2.0
Dotnet.Script.DependencyModel		netstandard2.0
Dotnet.Script.DependencyModel.Nuget		netstandard2.0

Installing

Prerequisites

The only thing we need to install is .NET Core 3.1 or .NET 5.0 SDK.

.NET Core Global Tool

.NET Core 2.1 introduced the concept of global tools meaning that you can install dotnet-script using nothing but the .NET CLI.

dotnet tool install -g dotnet-script

You can invoke the tool using the following command: dotnet-script
Tool 'dotnet-script' (version '0.22.0') was successfully installed.

The advantage of this approach is that you can use the same command for installation across all platforms. .NET Core SDK also supports viewing a list of installed tools and their uninstallation.

dotnet tool list -g

Package Id         Version      Commands
---------------------------------------------
dotnet-script      0.22.0       dotnet-script

dotnet tool uninstall dotnet-script -g

Tool 'dotnet-script' (version '0.22.0') was successfully uninstalled.

Windows

choco install dotnet.script

We also provide a PowerShell script for installation.

(new-object Net.WebClient).DownloadString("https://raw.githubusercontent.com/filipw/dotnet-script/master/install/install.ps1") | iex

Linux and Mac

curl -s https://raw.githubusercontent.com/filipw/dotnet-script/master/install/install.sh | bash

If permission is denied we can try with sudo

curl -s https://raw.githubusercontent.com/filipw/dotnet-script/master/install/install.sh | sudo bash

Docker

A Dockerfile for running dotnet-script in a Linux container is available. Build:

cd build
docker build -t dotnet-script -f Dockerfile ..

And run:

docker run -it dotnet-script --version

Github

You can manually download all the releases in zip format from the GitHub releases page.

Usage

Our typical helloworld.csx might look like this:

Console.WriteLine("Hello world!");

That is all it takes and we can execute the script. Args are accessible via the global Args array.

dotnet script helloworld.csx

Scaffolding

Simply create a folder somewhere on your system and issue the following command.

dotnet script init

This will create main.csx along with the launch configuration needed to debug the script in VS Code.

.
├── .vscode
│   └── launch.json
├── main.csx
└── omnisharp.json

We can also initialize a folder using a custom filename.

dotnet script init custom.csx

Instead of main.csx which is the default, we now have a file named custom.csx.

.
├── .vscode
│   └── launch.json
├── custom.csx
└── omnisharp.json

Note: Executing dotnet script init inside a folder that already contains one or more script files will not create the main.csx file.

Running scripts

Scripts can be executed directly from the shell as if they were executables.

foo.csx arg1 arg2 arg3

OSX/Linux

Just like all scripts, on OSX/Linux you need to have a #! and mark the file as executable via chmod +x foo.csx. If you use dotnet script init to create your csx it will automatically have the #! directive and be marked as executable.

The OSX/Linux shebang directive should be #!/usr/bin/env dotnet-script

#!/usr/bin/env dotnet-script
Console.WriteLine("Hello world");

You can execute your script using dotnet script or dotnet-script, which allows you to pass arguments to control your script execution more.

foo.csx arg1 arg2 arg3
dotnet script foo.csx -- arg1 arg2 arg3
dotnet-script foo.csx -- arg1 arg2 arg3

Passing arguments to scripts

All arguments after -- are passed to the script in the following way:

dotnet script foo.csx -- arg1 arg2 arg3

Then you can access the arguments in the script context using the global Args collection:

foreach (var arg in Args)
{
    Console.WriteLine(arg);
}

All arguments before -- are processed by dotnet script. For example, the following command-line

dotnet script -d foo.csx -- -d

will pass the -d before -- to dotnet script and enable the debug mode whereas the -d after -- is passed to script for its own interpretation of the argument.

NuGet Packages

dotnet script has built-in support for referencing NuGet packages directly from within the script.

#r "nuget: AutoMapper, 6.1.0"

Note: Omnisharp needs to be restarted after adding a new package reference

Package Sources

We can define package sources using a NuGet.Config file in the script root folder. In addition to being used during execution of the script, it will also be used by OmniSharp that provides language services for packages resolved from these package sources.

As an alternative to maintaining a local NuGet.Config file we can define these package sources globally either at the user level or at the computer level as described in Configuring NuGet Behaviour

It is also possible to specify packages sources when executing the script.

dotnet script foo.csx -s https://SomePackageSource

Multiple packages sources can be specified like this:

dotnet script foo.csx -s https://SomePackageSource -s https://AnotherPackageSource

Creating DLLs or Exes from a CSX file

Dotnet-Script can create a standalone executable or DLL for your script.

Switch	Long switch	description
-o	--output	Directory where the published executable should be placed. Defaults to a 'publish' folder in the current directory.
-n	--name	The name for the generated DLL (executable not supported at this time). Defaults to the name of the script.
	--dll	Publish to a .dll instead of an executable.
-c	--configuration	Configuration to use for publishing the script [Release/Debug]. Default is "Debug"
-d	--debug	Enables debug output.
-r	--runtime	The runtime used when publishing the self contained executable. Defaults to your current runtime.

The executable you can run directly independent of dotnet install, while the DLL can be run using the dotnet CLI like this:

dotnet script exec {path_to_dll} -- arg1 arg2

Caching

We provide two types of caching, the dependency cache and the execution cache which is explained in detail below. In order for any of these caches to be enabled, it is required that all NuGet package references are specified using an exact version number. The reason for this constraint is that we need to make sure that we don't execute a script with a stale dependency graph.

Dependency Cache

In order to resolve the dependencies for a script, a dotnet restore is executed under the hood to produce a project.assets.json file from which we can figure out all the dependencies we need to add to the compilation. This is an out-of-process operation and represents a significant overhead to the script execution. So this cache works by looking at all the dependencies specified in the script(s) either in the form of NuGet package references or assembly file references. If these dependencies matches the dependencies from the last script execution, we skip the restore and read the dependencies from the already generated project.assets.json file. If any of the dependencies has changed, we must restore again to obtain the new dependency graph.

Execution cache

In order to execute a script it needs to be compiled first and since that is a CPU and time consuming operation, we make sure that we only compile when the source code has changed. This works by creating a SHA256 hash from all the script files involved in the execution. This hash is written to a temporary location along with the DLL that represents the result of the script compilation. When a script is executed the hash is computed and compared with the hash from the previous compilation. If they match there is no need to recompile and we run from the already compiled DLL. If the hashes don't match, the cache is invalidated and we recompile.

You can override this automatic caching by passing --no-cache flag, which will bypass both caches and cause dependency resolution and script compilation to happen every time we execute the script.

Cache Location

The temporary location used for caches is a sub-directory named dotnet-script under (in order of priority):

1. The path specified for the value of the environment variable named DOTNET_SCRIPT_CACHE_LOCATION, if defined and value is not empty.
2. Linux distributions only: $XDG_CACHE_HOME if defined otherwise $HOME/.cache
3. macOS only: ~/Library/Caches
4. The value returned by Path.GetTempPath for the platform.

 

Debugging

The days of debugging scripts using Console.WriteLine are over. One major feature of dotnet script is the ability to debug scripts directly in VS Code. Just set a breakpoint anywhere in your script file(s) and hit F5(start debugging)

Script Packages

Script packages are a way of organizing reusable scripts into NuGet packages that can be consumed by other scripts. This means that we now can leverage scripting infrastructure without the need for any kind of bootstrapping.

Creating a script package

A script package is just a regular NuGet package that contains script files inside the content or contentFiles folder.

The following example shows how the scripts are laid out inside the NuGet package according to the standard convention .

└── contentFiles
    └── csx
        └── netstandard2.0
            └── main.csx

This example contains just the main.csx file in the root folder, but packages may have multiple script files either in the root folder or in subfolders below the root folder.

When loading a script package we will look for an entry point script to be loaded. This entry point script is identified by one of the following.

• A script called main.csx in the root folder
• A single script file in the root folder

If the entry point script cannot be determined, we will simply load all the scripts files in the package.

The advantage with using an entry point script is that we can control loading other scripts from the package.

Consuming a script package

To consume a script package all we need to do specify the NuGet package in the #loaddirective.

The following example loads the simple-targets package that contains script files to be included in our script.

#load "nuget:simple-targets-csx, 6.0.0"

using static SimpleTargets;
var targets = new TargetDictionary();

targets.Add("default", () => Console.WriteLine("Hello, world!"));

Run(Args, targets);

Note: Debugging also works for script packages so that we can easily step into the scripts that are brought in using the #load directive.

Remote Scripts

Scripts don't actually have to exist locally on the machine. We can also execute scripts that are made available on an http(s) endpoint.

This means that we can create a Gist on Github and execute it just by providing the URL to the Gist.

This Gist contains a script that prints out "Hello World"

We can execute the script like this

dotnet script https://gist.githubusercontent.com/seesharper/5d6859509ea8364a1fdf66bbf5b7923d/raw/0a32bac2c3ea807f9379a38e251d93e39c8131cb/HelloWorld.csx

That is a pretty long URL, so why don't make it a TinyURL like this:

dotnet script https://tinyurl.com/y8cda9zt

Script Location

A pretty common scenario is that we have logic that is relative to the script path. We don't want to require the user to be in a certain directory for these paths to resolve correctly so here is how to provide the script path and the script folder regardless of the current working directory.

public static string GetScriptPath([CallerFilePath] string path = null) => path;
public static string GetScriptFolder([CallerFilePath] string path = null) => Path.GetDirectoryName(path);

Tip: Put these methods as top level methods in a separate script file and #load that file wherever access to the script path and/or folder is needed.

REPL

This release contains a C# REPL (Read-Evaluate-Print-Loop). The REPL mode ("interactive mode") is started by executing dotnet-script without any arguments.

The interactive mode allows you to supply individual C# code blocks and have them executed as soon as you press Enter. The REPL is configured with the same default set of assembly references and using statements as regular CSX script execution.

Basic usage

Once dotnet-script starts you will see a prompt for input. You can start typing C# code there.

~$ dotnet script
> var x = 1;
> x+x
2

If you submit an unterminated expression into the REPL (no ; at the end), it will be evaluated and the result will be serialized using a formatter and printed in the output. This is a bit more interesting than just calling ToString() on the object, because it attempts to capture the actual structure of the object. For example:

~$ dotnet script
> var x = new List<string>();
> x.Add("foo");
> x
List<string>(1) { "foo" }
> x.Add("bar");
> x
List<string>(2) { "foo", "bar" }
>

Inline Nuget packages

REPL also supports inline Nuget packages - meaning the Nuget packages can be installed into the REPL from within the REPL. This is done via our #r and #load from Nuget support and uses identical syntax.

~$ dotnet script
> #r "nuget: Automapper, 6.1.1"
> using AutoMapper;
> typeof(MapperConfiguration)
[AutoMapper.MapperConfiguration]
> #load "nuget: simple-targets-csx, 6.0.0";
> using static SimpleTargets;
> typeof(TargetDictionary)
[Submission#0+SimpleTargets+TargetDictionary]

Multiline mode

Using Roslyn syntax parsing, we also support multiline REPL mode. This means that if you have an uncompleted code block and press Enter, we will automatically enter the multiline mode. The mode is indicated by the * character. This is particularly useful for declaring classes and other more complex constructs.

~$ dotnet script
> class Foo {
* public string Bar {get; set;}
* }
> var foo = new Foo();

REPL commands

Aside from the regular C# script code, you can invoke the following commands (directives) from within the REPL:

Command	Description
#load	Load a script into the REPL (same as #load usage in CSX)
#r	Load an assembly into the REPL (same as #r usage in CSX)
#reset	Reset the REPL back to initial state (without restarting it)
#cls	Clear the console screen without resetting the REPL state
#exit	Exits the REPL

Seeding REPL with a script

You can execute a CSX script and, at the end of it, drop yourself into the context of the REPL. This way, the REPL becomes "seeded" with your code - all the classes, methods or variables are available in the REPL context. This is achieved by running a script with an -i flag.

For example, given the following CSX script:

var msg = "Hello World";
Console.WriteLine(msg);

When you run this with the -i flag, Hello World is printed, REPL starts and msg variable is available in the REPL context.

~$ dotnet script foo.csx -i
Hello World
>

You can also seed the REPL from inside the REPL - at any point - by invoking a #load directive pointed at a specific file. For example:

~$ dotnet script
> #load "foo.csx"
Hello World
>

Piping

The following example shows how we can pipe data in and out of a script.

The UpperCase.csx script simply converts the standard input to upper case and writes it back out to standard output.

using (var streamReader = new StreamReader(Console.OpenStandardInput()))
{
    Write(streamReader.ReadToEnd().ToUpper());
}

We can now simply pipe the output from one command into our script like this.

echo "This is some text" | dotnet script UpperCase.csx
THIS IS SOME TEXT

Debugging

The first thing we need to do add the following to the launch.config file that allows VS Code to debug a running process.

{
    "name": ".NET Core Attach",
    "type": "coreclr",
    "request": "attach",
    "processId": "${command:pickProcess}"
}

To debug this script we need a way to attach the debugger in VS Code and the simplest thing we can do here is to wait for the debugger to attach by adding this method somewhere.

public static void WaitForDebugger()
{
    Console.WriteLine("Attach Debugger (VS Code)");
    while(!Debugger.IsAttached)
    {
    }
}

To debug the script when executing it from the command line we can do something like

WaitForDebugger();
using (var streamReader = new StreamReader(Console.OpenStandardInput()))
{
    Write(streamReader.ReadToEnd().ToUpper()); // <- SET BREAKPOINT HERE
}

Now when we run the script from the command line we will get

$ echo "This is some text" | dotnet script UpperCase.csx
Attach Debugger (VS Code)

This now gives us a chance to attach the debugger before stepping into the script and from VS Code, select the .NET Core Attach debugger and pick the process that represents the executing script.

Once that is done we should see our breakpoint being hit.

Configuration(Debug/Release)

By default, scripts will be compiled using the debug configuration. This is to ensure that we can debug a script in VS Code as well as attaching a debugger for long running scripts.

There are however situations where we might need to execute a script that is compiled with the release configuration. For instance, running benchmarks using BenchmarkDotNet is not possible unless the script is compiled with the release configuration.

We can specify this when executing the script.

dotnet script foo.csx -c release

 

Nullable reference types

Starting from version 0.50.0, dotnet-script supports .Net Core 3.0 and all the C# 8 features. The way we deal with nullable references types in dotnet-script is that we turn every warning related to nullable reference types into compiler errors. This means every warning between CS8600 and CS8655 are treated as an error when compiling the script.

Nullable references types are turned off by default and the way we enable it is using the #nullable enable compiler directive. This means that existing scripts will continue to work, but we can now opt-in on this new feature.

#!/usr/bin/env dotnet-script

#nullable enable

string name = null;

Trying to execute the script will result in the following error

main.csx(5,15): error CS8625: Cannot convert null literal to non-nullable reference type.

We will also see this when working with scripts in VS Code under the problems panel.

Download Details:
Author: filipw
Source Code: https://github.com/filipw/dotnet-script
License: MIT License

#dotnet  #aspdotnet  #csharp