1657735200
A Fully Customizable Swift Library for Easy Creating UITableView Based
Former is a fully customizable Swift library for easy creating UITableView based form.
Submitting Issues
Click HERE to get started with filing a bug report. Please use this template to ensure that your issue doesn't get closed due to lack of information.
Submitting Feature Requests
Click HERE to get started with filing a feature request. Please use this template to ensure that your feature request doesn't get denied due to lack of information. Also please keep in mind that while we desire to make this work as well as possible for everyone we won't be able to accomodate all feature requests due to lack of time or alignment with the direction of the plugin, and you may need to consider contributing even if we agree that a feature would benefit the plugin.
Demo
Contents
Requirements
- Xcode 10+
- Swift 4.2+
- iOS 10.0+
Still wanna use iOS7 and swift 2.2 or 2.3?
-> You can use 1.4.0 instead.
Installation
CocoaPods
Add the following line to your Podfile:
use_frameworks!
target 'YOUR_TARGET_NAME' do
pod 'Former'
end
Carthage
Add the following line to your Cartfile:
github "ra1028/Former"
Usage
You can set the cell's appearance and events-callback at the same time.
ViewController and Cell do not need to override the provided defaults.
Simple Example
import Former
final class ViewController: FormViewController {
override func viewDidLoad() {
super.viewDidLoad()
let labelRow = LabelRowFormer<FormLabelCell>()
.configure { row in
row.text = "Label Cell"
}.onSelected { row in
// Do Something
}
let inlinePickerRow = InlinePickerRowFormer<FormInlinePickerCell, Int>() {
$0.titleLabel.text = "Inline Picker Cell"
}.configure { row in
row.pickerItems = (1...5).map {
InlinePickerItem(title: "Option\($0)", value: Int($0))
}
}.onValueChanged { item in
// Do Something
}
let header = LabelViewFormer<FormLabelHeaderView>() { view in
view.titleLabel.text = "Label Header"
}
let section = SectionFormer(rowFormer: labelRow, inlinePickerRow)
.set(headerViewFormer: header)
former.append(sectionFormer: section)
}
}
RowFormer
RowFormer is the base class of the class that manages the cell. A cell that is managed by the RowFormer class should conform to the corresponding protocol. Each of the RowFormer classes exposes event handling in functions named "on*" (e.g., onSelected, onValueChanged, etc...)
Default provided RowFormer classes and the protocols that corresponding to it are listed below.
| Demo | Class | Protocol | Default provided cell |
|---|---|---|---|
| Free | CustomRowFormer | None | None |
 | LabelRowFormer | LabelFormableRow | FormLabelCell |
 | TextFieldRowFormer | TextFieldFormableRow | FormTextFieldCell |
 | TextViewRowFormer | TextViewFormableRow | FormTextViewCell |
 | CheckRowFormer | CheckFormableRow | FormCheckCell |
 | SwitchRowFormer | SwitchFormableRow | FormSwitchCell |
 | StepperRowFormer | StepperFormableRow | FormStepperCell |
 | SegmentedRowFormer | SegmentedFormableRow | FormSegmentedCell |
 | SliderRowFormer | SliderFormableRow | FormSliderCell |
 | PickerRowFormer | PickerFormableRow | FormPickerCell |
 | DatePickerRowFormer | DatePickerFormableRow | FormDatePickerCell |
 | SelectorPickerRowFormer | SelectorPickerFormableRow | FormSelectorPickerCell |
 | SelectorDatePickerRowFormer | SelectorDatePickerFormableRow | FormSelectorDatePickerCell |
 | InlinePickerRowFormer | InlinePickerFormableRow | FormInlinePickerCell |
 | InlineDatePickerRowFormer | InlineDatePickerFormableRow | FormInlineDatePickerCell |
example with LabelRowFormer
let labelRow = LabelRowFormer<YourLabelCell>(instantiateType: .Nib(nibName: "YourLabelCell")) {
$0.titleLabel.textColor = .blackColor()
}.configure { row in
row.rowHeight = 44
row.text = "Label Cell"
}.onSelected { row in
print("\(row.text) Selected !!")
}
update the cell
row.update()
row.update { row in
row.text = "Updated title"
}
row.cellUpdate { cell in
cell.titleLabel.textColor = .redColor()
}
get cell instance
let cell = row.cell
print(cell.titleLabel.text)
set dynamic row height
row.dynamicRowHeight { tableView, indexPath -> CGFloat in
return 100
}
ViewFormer
ViewFormer is base class of the class that manages the HeaderFooterView.
A HeaderFooterView that is managed by the ViewFormer class should conform to the corresponding protocol. Default provided ViewFormer classes and the protocols that correspond to it are listed below.
| Demo | Class | Protocol | Default provided cell |
|---|---|---|---|
| Free | CustomViewFormer | None | None |
 | LabelViewFormer | LabelFormableView | FormLabelHeaderView FormLabelFooterView |
example with LabelViewFormer
let headerView = LabelViewFormer<YourLabelView>(instantiateType: .Nib(nibName: "YourLabelView")) {
$0.titleLabel.textColor = .blackColor()
}.configure { view in
view.viewHeight = 30
view.text = "Label HeaderFooter View"
}
SectionFormer
SectionFormer is a class that represents the Section of TableView.
SectionFormer can append, add, insert, remove the RowFormer and set the ViewFormer.
example
let section = SectionFormer(rowFormer: row1, row2, row3)
.set(headerViewFormer: headerView)
.set(footerViewFormer: footerView)
add the cell
section.append(rowFormer: row1, row2, row3)
section.add(rowFormers: rows)
section.insert(rowFormer: row, toIndex: 3)
section.insert(rowFormer: row, below: otherRow)
// etc...
remove the cell
section.remove(0)
section.remove(0...5)
section.remove(rowFormer: row)
// etc...
set the HeaderFooterViewe
section.set(headerViewFormer: headerView)
section.set(footerViewFormer: footerView)
Former
Former is a class that manages the entire form.
Examples is below.
add the section or cell
former.append(sectionFormer: row)
former.add(sectionFormers: rows)
former.insert(sectionFormer: section, toSection: 0)
former.insert(rowFormer: row, toIndexPath: indexPath)
former.insert(sectionFormer: section, above: otherSection)
former.insert(rowFormers: row, below: otherRow)
// etc...
// with animation
former.insertUpdate(sectionFormer: section, toSection: 0, rowAnimation: .Automatic)
former.insertUpdate(rowFormer: row, toIndexPath: indexPath, rowAnimation: .Left)
former.insertUpdate(sectionFormer: section, below: otherSection, rowAnimation: .Fade)
former.insertUpdate(rowFormers: rows, above: otherRow, rowAnimation: .Bottom)
// etc...
remove the section or cell
former.removeAll()
former.remove(rowFormer: row1, row2)
former.remove(sectionFormer: section1, section2)
// etc...
// with animation
former.removeAllUpdate(.Fade)
former.removeUpdate(sectionFormers: sections, rowAnimation: .Middle)
// etc...
Select and deselect the cell
former.select(indexPath: indexPath, animated: true, scrollPosition: .Middle)
former.select(rowFormer: row, animated: true)
former.deselect(true)
// etc...
end editing
former.endEditing()
become editing next/previous cell
if former.canBecomeEditingNext() {
former.becomeEditingNext()
}
if former.canBecomeEditingPrevious() {
former.becomeEditingPrevious()
}
functions to setting event handling
public func onCellSelected(handler: (NSIndexPath -> Void)) -> Self
public func onScroll(handler: ((scrollView: UIScrollView) -> Void)) -> Self
public func onBeginDragging(handler: (UIScrollView -> Void)) -> Self
public func willDeselectCell(handler: (NSIndexPath -> NSIndexPath?)) -> Self
public func willDisplayCell(handler: (NSIndexPath -> Void)) -> Self
public func willDisplayHeader(handler: (/*section:*/Int -> Void)) -> Self
public func willDisplayFooter(handler: (/*section:*/Int -> Void)) -> Self
public func didDeselectCell(handler: (NSIndexPath -> Void)) -> Self
public func didEndDisplayingCell(handler: (NSIndexPath -> Void)) -> Self
public func didEndDisplayingHeader(handler: (/*section:*/Int -> Void)) -> Self
public func didEndDisplayingFooter(handler: (/*section:*/Int -> Void)) -> Self
public func didHighlightCell(handler: (NSIndexPath -> Void)) -> Self
public func didUnHighlightCell(handler: (NSIndexPath -> Void)) -> Self
Customizability
ViewController
There is no need to inherit from the FormViewController class.
Instead, create an instance of UITableView and Former, as in the following example.
final class YourViewController: UIViewController {
private let tableView: UITableView = UITableView(frame: CGRect.zero, style: .Grouped) // It may be IBOutlet. Not forget to addSubview.
private lazy var former: Former = Former(tableView: self.tableView)
...
Cell There is likewise no need to inherit from the default provided cell class (FormLabelCell etc ...); only conform to the corresponding protocol. You can use Nibs, of course. An example with LabelRowFormer:
final class YourCell: UITableViewCell, LabelFormableRow {
// MARK: LabelFormableRow
func formTextLabel() -> UILabel? {
return titleLabel
}
func formSubTextLabel() -> UILabel? {
return subTitleLabel
}
func updateWithRowFormer(rowFormer: RowFormer) {
// Do something
}
// MARK: UITableViewCell
var titleLabel: UILabel?
var subTitleLabel: UILabel?
...
RowFormer If you want to create a custom RowFormer, make your class inherit from BaseRowFormer and comply with the Formable protocol.
It must conform to ConfigurableInlineForm. In the case of InlineRowFomer, conform to the UpdatableSelectorForm case of SelectorRowFormer. Please look at the source code for details.
Examples of RowFormer using cells with two UITextFields:
public protocol DoubleTextFieldFormableRow: FormableRow {
func formTextField1() -> UITextField
func formTextField2() -> UITextField
}
public final class DoubleTextFieldRowFormer<T: UITableViewCell where T: DoubleTextFieldFormableRow>
: BaseRowFormer<T>, Formable {
// MARK: Public
override public var canBecomeEditing: Bool {
return enabled
}
public var text1: String?
public var text2: String?
public required init(instantiateType: Former.InstantiateType = .Class, cellSetup: (T -> Void)? = nil) {
super.init(instantiateType: instantiateType, cellSetup: cellSetup)
}
public final func onText1Changed(handler: (String -> Void)) -> Self {
onText1Changed = handler
return self
}
public final func onText2Changed(handler: (String -> Void)) -> Self {
onText2Changed = handler
return self
}
open override func cellInitialized(cell: T) {
super.cellInitialized(cell)
cell.formTextField1().addTarget(self, action: "text1Changed:", forControlEvents: .EditingChanged)
cell.formTextField2().addTarget(self, action: "text2Changed:", forControlEvents: .EditingChanged)
}
open override func update() {
super.update()
cell.selectionStyle = .None
let textField1 = cell.formTextField1()
let textField2 = cell.formTextField2()
textField1.text = text1
textField2.text = text2
}
// MARK: Private
private final var onText1Changed: (String -> Void)?
private final var onText2Changed: (String -> Void)?
private dynamic func text1Changed(textField: UITextField) {
if enabled {
let text = textField.text ?? ""
self.text1 = text
onText1Changed?(text)
}
}
private dynamic func text2Changed(textField: UITextField) {
if enabled {
let text = textField.text ?? ""
self.text2 = text
onText2Changed?(text)
}
}
}
Contributing
If you're interesting in helping us improve and maintain Former, it is highly encouraged that you fork the repository and submit a pull request with your updates.
If you do chose to submit a pull request, please make sure to clearly document what changes you have made in the description of the PR.
License
Former is available under the MIT license. See the LICENSE file for more info.
Author: ra1028
Source code: https://github.com/ra1028/Former
License: MIT license
#swift
What is GEEK
Buddha Community
1655630160
PyTumblr: A Python Tumblr API v2 Client
PyTumblr
Installation
Install via pip:
$ pip install pytumblrInstall from source:
$ git clone https://github.com/tumblr/pytumblr.git
$ cd pytumblr
$ python setup.py installUsage
Create a client
A pytumblr.TumblrRestClient is the object you'll make all of your calls to the Tumblr API through. Creating one is this easy:
client = pytumblr.TumblrRestClient(
'<consumer_key>',
'<consumer_secret>',
'<oauth_token>',
'<oauth_secret>',
)
client.info() # Grabs the current user informationTwo easy ways to get your credentials to are:
- The built-in
interactive_console.pytool (if you already have a consumer key & secret) - The Tumblr API console at https://api.tumblr.com/console
- Get sample login code at https://api.tumblr.com/console/calls/user/info
Supported Methods
User Methods
client.info() # get information about the authenticating user
client.dashboard() # get the dashboard for the authenticating user
client.likes() # get the likes for the authenticating user
client.following() # get the blogs followed by the authenticating user
client.follow('codingjester.tumblr.com') # follow a blog
client.unfollow('codingjester.tumblr.com') # unfollow a blog
client.like(id, reblogkey) # like a post
client.unlike(id, reblogkey) # unlike a postBlog Methods
client.blog_info(blogName) # get information about a blog
client.posts(blogName, **params) # get posts for a blog
client.avatar(blogName) # get the avatar for a blog
client.blog_likes(blogName) # get the likes on a blog
client.followers(blogName) # get the followers of a blog
client.blog_following(blogName) # get the publicly exposed blogs that [blogName] follows
client.queue(blogName) # get the queue for a given blog
client.submission(blogName) # get the submissions for a given blogPost Methods
Creating posts
PyTumblr lets you create all of the various types that Tumblr supports. When using these types there are a few defaults that are able to be used with any post type.
The default supported types are described below.
- state - a string, the state of the post. Supported types are published, draft, queue, private
- tags - a list, a list of strings that you want tagged on the post. eg: ["testing", "magic", "1"]
- tweet - a string, the string of the customized tweet you want. eg: "Man I love my mega awesome post!"
- date - a string, the customized GMT that you want
- format - a string, the format that your post is in. Support types are html or markdown
- slug - a string, the slug for the url of the post you want
We'll show examples throughout of these default examples while showcasing all the specific post types.
Creating a photo post
Creating a photo post supports a bunch of different options plus the described default options * caption - a string, the user supplied caption * link - a string, the "click-through" url for the photo * source - a string, the url for the photo you want to use (use this or the data parameter) * data - a list or string, a list of filepaths or a single file path for multipart file upload
#Creates a photo post using a source URL
client.create_photo(blogName, state="published", tags=["testing", "ok"],
source="https://68.media.tumblr.com/b965fbb2e501610a29d80ffb6fb3e1ad/tumblr_n55vdeTse11rn1906o1_500.jpg")
#Creates a photo post using a local filepath
client.create_photo(blogName, state="queue", tags=["testing", "ok"],
tweet="Woah this is an incredible sweet post [URL]",
data="/Users/johnb/path/to/my/image.jpg")
#Creates a photoset post using several local filepaths
client.create_photo(blogName, state="draft", tags=["jb is cool"], format="markdown",
data=["/Users/johnb/path/to/my/image.jpg", "/Users/johnb/Pictures/kittens.jpg"],
caption="## Mega sweet kittens")Creating a text post
Creating a text post supports the same options as default and just a two other parameters * title - a string, the optional title for the post. Supports markdown or html * body - a string, the body of the of the post. Supports markdown or html
#Creating a text post
client.create_text(blogName, state="published", slug="testing-text-posts", title="Testing", body="testing1 2 3 4")Creating a quote post
Creating a quote post supports the same options as default and two other parameter * quote - a string, the full text of the qote. Supports markdown or html * source - a string, the cited source. HTML supported
#Creating a quote post
client.create_quote(blogName, state="queue", quote="I am the Walrus", source="Ringo")Creating a link post
- title - a string, the title of post that you want. Supports HTML entities.
- url - a string, the url that you want to create a link post for.
- description - a string, the desciption of the link that you have
#Create a link post
client.create_link(blogName, title="I like to search things, you should too.", url="https://duckduckgo.com",
description="Search is pretty cool when a duck does it.")Creating a chat post
Creating a chat post supports the same options as default and two other parameters * title - a string, the title of the chat post * conversation - a string, the text of the conversation/chat, with diablog labels (no html)
#Create a chat post
chat = """John: Testing can be fun!
Renee: Testing is tedious and so are you.
John: Aw.
"""
client.create_chat(blogName, title="Renee just doesn't understand.", conversation=chat, tags=["renee", "testing"])Creating an audio post
Creating an audio post allows for all default options and a has 3 other parameters. The only thing to keep in mind while dealing with audio posts is to make sure that you use the external_url parameter or data. You cannot use both at the same time. * caption - a string, the caption for your post * external_url - a string, the url of the site that hosts the audio file * data - a string, the filepath of the audio file you want to upload to Tumblr
#Creating an audio file
client.create_audio(blogName, caption="Rock out.", data="/Users/johnb/Music/my/new/sweet/album.mp3")
#lets use soundcloud!
client.create_audio(blogName, caption="Mega rock out.", external_url="https://soundcloud.com/skrillex/sets/recess")Creating a video post
Creating a video post allows for all default options and has three other options. Like the other post types, it has some restrictions. You cannot use the embed and data parameters at the same time. * caption - a string, the caption for your post * embed - a string, the HTML embed code for the video * data - a string, the path of the file you want to upload
#Creating an upload from YouTube
client.create_video(blogName, caption="Jon Snow. Mega ridiculous sword.",
embed="http://www.youtube.com/watch?v=40pUYLacrj4")
#Creating a video post from local file
client.create_video(blogName, caption="testing", data="/Users/johnb/testing/ok/blah.mov")Editing a post
Updating a post requires you knowing what type a post you're updating. You'll be able to supply to the post any of the options given above for updates.
client.edit_post(blogName, id=post_id, type="text", title="Updated")
client.edit_post(blogName, id=post_id, type="photo", data="/Users/johnb/mega/awesome.jpg")Reblogging a Post
Reblogging a post just requires knowing the post id and the reblog key, which is supplied in the JSON of any post object.
client.reblog(blogName, id=125356, reblog_key="reblog_key")Deleting a post
Deleting just requires that you own the post and have the post id
client.delete_post(blogName, 123456) # Deletes your post :(A note on tags: When passing tags, as params, please pass them as a list (not a comma-separated string):
client.create_text(blogName, tags=['hello', 'world'], ...)Getting notes for a post
In order to get the notes for a post, you need to have the post id and the blog that it is on.
data = client.notes(blogName, id='123456')The results include a timestamp you can use to make future calls.
data = client.notes(blogName, id='123456', before_timestamp=data["_links"]["next"]["query_params"]["before_timestamp"])Tagged Methods
# get posts with a given tag
client.tagged(tag, **params)Using the interactive console
This client comes with a nice interactive console to run you through the OAuth process, grab your tokens (and store them for future use).
You'll need pyyaml installed to run it, but then it's just:
$ python interactive-console.pyand away you go! Tokens are stored in ~/.tumblr and are also shared by other Tumblr API clients like the Ruby client.
Running tests
The tests (and coverage reports) are run with nose, like this:
python setup.py testAuthor: tumblr
Source Code: https://github.com/tumblr/pytumblr
License: Apache-2.0 license
1669003576
Exploring Mutable and Immutable in Python
In this Python article, let's learn about Mutable and Immutable in Python.
Mutable and Immutable in Python
Mutable is a fancy way of saying that the internal state of the object is changed/mutated. So, the simplest definition is: An object whose internal state can be changed is mutable. On the other hand, immutable doesn’t allow any change in the object once it has been created.
Both of these states are integral to Python data structure. If you want to become more knowledgeable in the entire Python Data Structure, take this free course which covers multiple data structures in Python including tuple data structure which is immutable. You will also receive a certificate on completion which is sure to add value to your portfolio.
Mutable Definition
Mutable is when something is changeable or has the ability to change. In Python, ‘mutable’ is the ability of objects to change their values. These are often the objects that store a collection of data.
Immutable Definition
Immutable is the when no change is possible over time. In Python, if the value of an object cannot be changed over time, then it is known as immutable. Once created, the value of these objects is permanent.
List of Mutable and Immutable objects
Objects of built-in type that are mutable are:
- Lists
- Sets
- Dictionaries
- User-Defined Classes (It purely depends upon the user to define the characteristics)
Objects of built-in type that are immutable are:
- Numbers (Integer, Rational, Float, Decimal, Complex & Booleans)
- Strings
- Tuples
- Frozen Sets
- User-Defined Classes (It purely depends upon the user to define the characteristics)
Object mutability is one of the characteristics that makes Python a dynamically typed language. Though Mutable and Immutable in Python is a very basic concept, it can at times be a little confusing due to the intransitive nature of immutability.
Objects in Python
In Python, everything is treated as an object. Every object has these three attributes:
- Identity – This refers to the address that the object refers to in the computer’s memory.
- Type – This refers to the kind of object that is created. For example- integer, list, string etc.
- Value – This refers to the value stored by the object. For example – List=[1,2,3] would hold the numbers 1,2 and 3
While ID and Type cannot be changed once it’s created, values can be changed for Mutable objects.
Check out this free python certificate course to get started with Python.
Mutable Objects in Python
I believe, rather than diving deep into the theory aspects of mutable and immutable in Python, a simple code would be the best way to depict what it means in Python. Hence, let us discuss the below code step-by-step:
#Creating a list which contains name of Indian cities
cities = [‘Delhi’, ‘Mumbai’, ‘Kolkata’]
# Printing the elements from the list cities, separated by a comma & space
for city in cities:
print(city, end=’, ’)
Output [1]: Delhi, Mumbai, Kolkata
#Printing the location of the object created in the memory address in hexadecimal format
print(hex(id(cities)))
Output [2]: 0x1691d7de8c8
#Adding a new city to the list cities
cities.append(‘Chennai’)
#Printing the elements from the list cities, separated by a comma & space
for city in cities:
print(city, end=’, ’)
Output [3]: Delhi, Mumbai, Kolkata, Chennai
#Printing the location of the object created in the memory address in hexadecimal format
print(hex(id(cities)))
Output [4]: 0x1691d7de8c8
The above example shows us that we were able to change the internal state of the object ‘cities’ by adding one more city ‘Chennai’ to it, yet, the memory address of the object did not change. This confirms that we did not create a new object, rather, the same object was changed or mutated. Hence, we can say that the object which is a type of list with reference variable name ‘cities’ is a MUTABLE OBJECT.
Let us now discuss the term IMMUTABLE. Considering that we understood what mutable stands for, it is obvious that the definition of immutable will have ‘NOT’ included in it. Here is the simplest definition of immutable– An object whose internal state can NOT be changed is IMMUTABLE.
Again, if you try and concentrate on different error messages, you have encountered, thrown by the respective IDE; you use you would be able to identify the immutable objects in Python. For instance, consider the below code & associated error message with it, while trying to change the value of a Tuple at index 0.
#Creating a Tuple with variable name ‘foo’
foo = (1, 2)
#Changing the index[0] value from 1 to 3
foo[0] = 3
TypeError: 'tuple' object does not support item assignment
Immutable Objects in Python
Once again, a simple code would be the best way to depict what immutable stands for. Hence, let us discuss the below code step-by-step:
#Creating a Tuple which contains English name of weekdays
weekdays = ‘Sunday’, ‘Monday’, ‘Tuesday’, ‘Wednesday’, ‘Thursday’, ‘Friday’, ‘Saturday’
# Printing the elements of tuple weekdays
print(weekdays)
Output [1]: (‘Sunday’, ‘Monday’, ‘Tuesday’, ‘Wednesday’, ‘Thursday’, ‘Friday’, ‘Saturday’)
#Printing the location of the object created in the memory address in hexadecimal format
print(hex(id(weekdays)))
Output [2]: 0x1691cc35090
#tuples are immutable, so you cannot add new elements, hence, using merge of tuples with the # + operator to add a new imaginary day in the tuple ‘weekdays’
weekdays += ‘Pythonday’,
#Printing the elements of tuple weekdays
print(weekdays)
Output [3]: (‘Sunday’, ‘Monday’, ‘Tuesday’, ‘Wednesday’, ‘Thursday’, ‘Friday’, ‘Saturday’, ‘Pythonday’)
#Printing the location of the object created in the memory address in hexadecimal format
print(hex(id(weekdays)))
Output [4]: 0x1691cc8ad68
This above example shows that we were able to use the same variable name that is referencing an object which is a type of tuple with seven elements in it. However, the ID or the memory location of the old & new tuple is not the same. We were not able to change the internal state of the object ‘weekdays’. The Python program manager created a new object in the memory address and the variable name ‘weekdays’ started referencing the new object with eight elements in it. Hence, we can say that the object which is a type of tuple with reference variable name ‘weekdays’ is an IMMUTABLE OBJECT.
Also Read: Understanding the Exploratory Data Analysis (EDA) in Python
Where can you use mutable and immutable objects:
Mutable objects can be used where you want to allow for any updates. For example, you have a list of employee names in your organizations, and that needs to be updated every time a new member is hired. You can create a mutable list, and it can be updated easily.
Immutability offers a lot of useful applications to different sensitive tasks we do in a network centred environment where we allow for parallel processing. By creating immutable objects, you seal the values and ensure that no threads can invoke overwrite/update to your data. This is also useful in situations where you would like to write a piece of code that cannot be modified. For example, a debug code that attempts to find the value of an immutable object.
Watch outs: Non transitive nature of Immutability:
OK! Now we do understand what mutable & immutable objects in Python are. Let’s go ahead and discuss the combination of these two and explore the possibilities. Let’s discuss, as to how will it behave if you have an immutable object which contains the mutable object(s)? Or vice versa? Let us again use a code to understand this behaviour–
#creating a tuple (immutable object) which contains 2 lists(mutable) as it’s elements
#The elements (lists) contains the name, age & gender
person = (['Ayaan', 5, 'Male'], ['Aaradhya', 8, 'Female'])
#printing the tuple
print(person)
Output [1]: (['Ayaan', 5, 'Male'], ['Aaradhya', 8, 'Female'])
#printing the location of the object created in the memory address in hexadecimal format
print(hex(id(person)))
Output [2]: 0x1691ef47f88
#Changing the age for the 1st element. Selecting 1st element of tuple by using indexing [0] then 2nd element of the list by using indexing [1] and assigning a new value for age as 4
person[0][1] = 4
#printing the updated tuple
print(person)
Output [3]: (['Ayaan', 4, 'Male'], ['Aaradhya', 8, 'Female'])
#printing the location of the object created in the memory address in hexadecimal format
print(hex(id(person)))
Output [4]: 0x1691ef47f88
In the above code, you can see that the object ‘person’ is immutable since it is a type of tuple. However, it has two lists as it’s elements, and we can change the state of lists (lists being mutable). So, here we did not change the object reference inside the Tuple, but the referenced object was mutated.
Also Read: Real-Time Object Detection Using TensorFlow
Same way, let’s explore how it will behave if you have a mutable object which contains an immutable object? Let us again use a code to understand the behaviour–
#creating a list (mutable object) which contains tuples(immutable) as it’s elements
list1 = [(1, 2, 3), (4, 5, 6)]
#printing the list
print(list1)
Output [1]: [(1, 2, 3), (4, 5, 6)]
#printing the location of the object created in the memory address in hexadecimal format
print(hex(id(list1)))
Output [2]: 0x1691d5b13c8 #changing object reference at index 0
list1[0] = (7, 8, 9)
#printing the list
Output [3]: [(7, 8, 9), (4, 5, 6)]#printing the location of the object created in the memory address in hexadecimal format
print(hex(id(list1)))
Output [4]: 0x1691d5b13c8
As an individual, it completely depends upon you and your requirements as to what kind of data structure you would like to create with a combination of mutable & immutable objects. I hope that this information will help you while deciding the type of object you would like to select going forward.
Before I end our discussion on IMMUTABILITY, allow me to use the word ‘CAVITE’ when we discuss the String and Integers. There is an exception, and you may see some surprising results while checking the truthiness for immutability. For instance:
#creating an object of integer type with value 10 and reference variable name ‘x’
x = 10
#printing the value of ‘x’
print(x)
Output [1]: 10
#Printing the location of the object created in the memory address in hexadecimal format
print(hex(id(x)))
Output [2]: 0x538fb560
#creating an object of integer type with value 10 and reference variable name ‘y’
y = 10
#printing the value of ‘y’
print(y)
Output [3]: 10
#Printing the location of the object created in the memory address in hexadecimal format
print(hex(id(y)))
Output [4]: 0x538fb560
As per our discussion and understanding, so far, the memory address for x & y should have been different, since, 10 is an instance of Integer class which is immutable. However, as shown in the above code, it has the same memory address. This is not something that we expected. It seems that what we have understood and discussed, has an exception as well.
Quick check – Python Data Structures
Immutability of Tuple
Tuples are immutable and hence cannot have any changes in them once they are created in Python. This is because they support the same sequence operations as strings. We all know that strings are immutable. The index operator will select an element from a tuple just like in a string. Hence, they are immutable.
Exceptions in immutability
Like all, there are exceptions in the immutability in python too. Not all immutable objects are really mutable. This will lead to a lot of doubts in your mind. Let us just take an example to understand this.
Consider a tuple ‘tup’.
Now, if we consider tuple tup = (‘GreatLearning’,[4,3,1,2]) ;
We see that the tuple has elements of different data types. The first element here is a string which as we all know is immutable in nature. The second element is a list which we all know is mutable. Now, we all know that the tuple itself is an immutable data type. It cannot change its contents. But, the list inside it can change its contents. So, the value of the Immutable objects cannot be changed but its constituent objects can. change its value.
FAQs
1. Difference between mutable vs immutable in Python?
| Mutable Object | Immutable Object |
| State of the object can be modified after it is created. | State of the object can’t be modified once it is created. |
| They are not thread safe. | They are thread safe |
| Mutable classes are not final. | It is important to make the class final before creating an immutable object. |
2. What are the mutable and immutable data types in Python?
- Some mutable data types in Python are:
list, dictionary, set, user-defined classes.
- Some immutable data types are:
int, float, decimal, bool, string, tuple, range.
3. Are lists mutable in Python?
Lists in Python are mutable data types as the elements of the list can be modified, individual elements can be replaced, and the order of elements can be changed even after the list has been created.
(Examples related to lists have been discussed earlier in this blog.)
4. Why are tuples called immutable types?
Tuple and list data structures are very similar, but one big difference between the data types is that lists are mutable, whereas tuples are immutable. The reason for the tuple’s immutability is that once the elements are added to the tuple and the tuple has been created; it remains unchanged.
A programmer would always prefer building a code that can be reused instead of making the whole data object again. Still, even though tuples are immutable, like lists, they can contain any Python object, including mutable objects.
5. Are sets mutable in Python?
A set is an iterable unordered collection of data type which can be used to perform mathematical operations (like union, intersection, difference etc.). Every element in a set is unique and immutable, i.e. no duplicate values should be there, and the values can’t be changed. However, we can add or remove items from the set as the set itself is mutable.
6. Are strings mutable in Python?
Strings are not mutable in Python. Strings are a immutable data types which means that its value cannot be updated.
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Original article source at: https://www.mygreatlearning.com
1657735200
A Fully Customizable Swift Library for Easy Creating UITableView Based
Former is a fully customizable Swift library for easy creating UITableView based form.
Submitting Issues
Click HERE to get started with filing a bug report. Please use this template to ensure that your issue doesn't get closed due to lack of information.
Submitting Feature Requests
Click HERE to get started with filing a feature request. Please use this template to ensure that your feature request doesn't get denied due to lack of information. Also please keep in mind that while we desire to make this work as well as possible for everyone we won't be able to accomodate all feature requests due to lack of time or alignment with the direction of the plugin, and you may need to consider contributing even if we agree that a feature would benefit the plugin.
Demo
Contents
Requirements
- Xcode 10+
- Swift 4.2+
- iOS 10.0+
Still wanna use iOS7 and swift 2.2 or 2.3?
-> You can use 1.4.0 instead.
Installation
CocoaPods
Add the following line to your Podfile:
use_frameworks!
target 'YOUR_TARGET_NAME' do
pod 'Former'
end
Carthage
Add the following line to your Cartfile:
github "ra1028/Former"
Usage
You can set the cell's appearance and events-callback at the same time.
ViewController and Cell do not need to override the provided defaults.
Simple Example
import Former
final class ViewController: FormViewController {
override func viewDidLoad() {
super.viewDidLoad()
let labelRow = LabelRowFormer<FormLabelCell>()
.configure { row in
row.text = "Label Cell"
}.onSelected { row in
// Do Something
}
let inlinePickerRow = InlinePickerRowFormer<FormInlinePickerCell, Int>() {
$0.titleLabel.text = "Inline Picker Cell"
}.configure { row in
row.pickerItems = (1...5).map {
InlinePickerItem(title: "Option\($0)", value: Int($0))
}
}.onValueChanged { item in
// Do Something
}
let header = LabelViewFormer<FormLabelHeaderView>() { view in
view.titleLabel.text = "Label Header"
}
let section = SectionFormer(rowFormer: labelRow, inlinePickerRow)
.set(headerViewFormer: header)
former.append(sectionFormer: section)
}
}
RowFormer
RowFormer is the base class of the class that manages the cell. A cell that is managed by the RowFormer class should conform to the corresponding protocol. Each of the RowFormer classes exposes event handling in functions named "on*" (e.g., onSelected, onValueChanged, etc...)
Default provided RowFormer classes and the protocols that corresponding to it are listed below.
| Demo | Class | Protocol | Default provided cell |
|---|---|---|---|
| Free | CustomRowFormer | None | None |
| LabelRowFormer | LabelFormableRow | FormLabelCell |
| TextFieldRowFormer | TextFieldFormableRow | FormTextFieldCell |
| TextViewRowFormer | TextViewFormableRow | FormTextViewCell |
| CheckRowFormer | CheckFormableRow | FormCheckCell |
| SwitchRowFormer | SwitchFormableRow | FormSwitchCell |
| StepperRowFormer | StepperFormableRow | FormStepperCell |
| SegmentedRowFormer | SegmentedFormableRow | FormSegmentedCell |
| SliderRowFormer | SliderFormableRow | FormSliderCell |
| PickerRowFormer | PickerFormableRow | FormPickerCell |
| DatePickerRowFormer | DatePickerFormableRow | FormDatePickerCell |
| SelectorPickerRowFormer | SelectorPickerFormableRow | FormSelectorPickerCell |
| SelectorDatePickerRowFormer | SelectorDatePickerFormableRow | FormSelectorDatePickerCell |
| InlinePickerRowFormer | InlinePickerFormableRow | FormInlinePickerCell |
| InlineDatePickerRowFormer | InlineDatePickerFormableRow | FormInlineDatePickerCell |
example with LabelRowFormer
let labelRow = LabelRowFormer<YourLabelCell>(instantiateType: .Nib(nibName: "YourLabelCell")) {
$0.titleLabel.textColor = .blackColor()
}.configure { row in
row.rowHeight = 44
row.text = "Label Cell"
}.onSelected { row in
print("\(row.text) Selected !!")
}
update the cell
row.update()
row.update { row in
row.text = "Updated title"
}
row.cellUpdate { cell in
cell.titleLabel.textColor = .redColor()
}
get cell instance
let cell = row.cell
print(cell.titleLabel.text)
set dynamic row height
row.dynamicRowHeight { tableView, indexPath -> CGFloat in
return 100
}
ViewFormer
ViewFormer is base class of the class that manages the HeaderFooterView.
A HeaderFooterView that is managed by the ViewFormer class should conform to the corresponding protocol. Default provided ViewFormer classes and the protocols that correspond to it are listed below.
| Demo | Class | Protocol | Default provided cell |
|---|---|---|---|
| Free | CustomViewFormer | None | None |
| LabelViewFormer | LabelFormableView | FormLabelHeaderView FormLabelFooterView |
example with LabelViewFormer
let headerView = LabelViewFormer<YourLabelView>(instantiateType: .Nib(nibName: "YourLabelView")) {
$0.titleLabel.textColor = .blackColor()
}.configure { view in
view.viewHeight = 30
view.text = "Label HeaderFooter View"
}
SectionFormer
SectionFormer is a class that represents the Section of TableView.
SectionFormer can append, add, insert, remove the RowFormer and set the ViewFormer.
example
let section = SectionFormer(rowFormer: row1, row2, row3)
.set(headerViewFormer: headerView)
.set(footerViewFormer: footerView)
add the cell
section.append(rowFormer: row1, row2, row3)
section.add(rowFormers: rows)
section.insert(rowFormer: row, toIndex: 3)
section.insert(rowFormer: row, below: otherRow)
// etc...
remove the cell
section.remove(0)
section.remove(0...5)
section.remove(rowFormer: row)
// etc...
set the HeaderFooterViewe
section.set(headerViewFormer: headerView)
section.set(footerViewFormer: footerView)
Former
Former is a class that manages the entire form.
Examples is below.
add the section or cell
former.append(sectionFormer: row)
former.add(sectionFormers: rows)
former.insert(sectionFormer: section, toSection: 0)
former.insert(rowFormer: row, toIndexPath: indexPath)
former.insert(sectionFormer: section, above: otherSection)
former.insert(rowFormers: row, below: otherRow)
// etc...
// with animation
former.insertUpdate(sectionFormer: section, toSection: 0, rowAnimation: .Automatic)
former.insertUpdate(rowFormer: row, toIndexPath: indexPath, rowAnimation: .Left)
former.insertUpdate(sectionFormer: section, below: otherSection, rowAnimation: .Fade)
former.insertUpdate(rowFormers: rows, above: otherRow, rowAnimation: .Bottom)
// etc...
remove the section or cell
former.removeAll()
former.remove(rowFormer: row1, row2)
former.remove(sectionFormer: section1, section2)
// etc...
// with animation
former.removeAllUpdate(.Fade)
former.removeUpdate(sectionFormers: sections, rowAnimation: .Middle)
// etc...
Select and deselect the cell
former.select(indexPath: indexPath, animated: true, scrollPosition: .Middle)
former.select(rowFormer: row, animated: true)
former.deselect(true)
// etc...
end editing
former.endEditing()
become editing next/previous cell
if former.canBecomeEditingNext() {
former.becomeEditingNext()
}
if former.canBecomeEditingPrevious() {
former.becomeEditingPrevious()
}
functions to setting event handling
public func onCellSelected(handler: (NSIndexPath -> Void)) -> Self
public func onScroll(handler: ((scrollView: UIScrollView) -> Void)) -> Self
public func onBeginDragging(handler: (UIScrollView -> Void)) -> Self
public func willDeselectCell(handler: (NSIndexPath -> NSIndexPath?)) -> Self
public func willDisplayCell(handler: (NSIndexPath -> Void)) -> Self
public func willDisplayHeader(handler: (/*section:*/Int -> Void)) -> Self
public func willDisplayFooter(handler: (/*section:*/Int -> Void)) -> Self
public func didDeselectCell(handler: (NSIndexPath -> Void)) -> Self
public func didEndDisplayingCell(handler: (NSIndexPath -> Void)) -> Self
public func didEndDisplayingHeader(handler: (/*section:*/Int -> Void)) -> Self
public func didEndDisplayingFooter(handler: (/*section:*/Int -> Void)) -> Self
public func didHighlightCell(handler: (NSIndexPath -> Void)) -> Self
public func didUnHighlightCell(handler: (NSIndexPath -> Void)) -> Self
Customizability
ViewController
There is no need to inherit from the FormViewController class.
Instead, create an instance of UITableView and Former, as in the following example.
final class YourViewController: UIViewController {
private let tableView: UITableView = UITableView(frame: CGRect.zero, style: .Grouped) // It may be IBOutlet. Not forget to addSubview.
private lazy var former: Former = Former(tableView: self.tableView)
...
Cell There is likewise no need to inherit from the default provided cell class (FormLabelCell etc ...); only conform to the corresponding protocol. You can use Nibs, of course. An example with LabelRowFormer:
final class YourCell: UITableViewCell, LabelFormableRow {
// MARK: LabelFormableRow
func formTextLabel() -> UILabel? {
return titleLabel
}
func formSubTextLabel() -> UILabel? {
return subTitleLabel
}
func updateWithRowFormer(rowFormer: RowFormer) {
// Do something
}
// MARK: UITableViewCell
var titleLabel: UILabel?
var subTitleLabel: UILabel?
...
RowFormer If you want to create a custom RowFormer, make your class inherit from BaseRowFormer and comply with the Formable protocol.
It must conform to ConfigurableInlineForm. In the case of InlineRowFomer, conform to the UpdatableSelectorForm case of SelectorRowFormer. Please look at the source code for details.
Examples of RowFormer using cells with two UITextFields:
public protocol DoubleTextFieldFormableRow: FormableRow {
func formTextField1() -> UITextField
func formTextField2() -> UITextField
}
public final class DoubleTextFieldRowFormer<T: UITableViewCell where T: DoubleTextFieldFormableRow>
: BaseRowFormer<T>, Formable {
// MARK: Public
override public var canBecomeEditing: Bool {
return enabled
}
public var text1: String?
public var text2: String?
public required init(instantiateType: Former.InstantiateType = .Class, cellSetup: (T -> Void)? = nil) {
super.init(instantiateType: instantiateType, cellSetup: cellSetup)
}
public final func onText1Changed(handler: (String -> Void)) -> Self {
onText1Changed = handler
return self
}
public final func onText2Changed(handler: (String -> Void)) -> Self {
onText2Changed = handler
return self
}
open override func cellInitialized(cell: T) {
super.cellInitialized(cell)
cell.formTextField1().addTarget(self, action: "text1Changed:", forControlEvents: .EditingChanged)
cell.formTextField2().addTarget(self, action: "text2Changed:", forControlEvents: .EditingChanged)
}
open override func update() {
super.update()
cell.selectionStyle = .None
let textField1 = cell.formTextField1()
let textField2 = cell.formTextField2()
textField1.text = text1
textField2.text = text2
}
// MARK: Private
private final var onText1Changed: (String -> Void)?
private final var onText2Changed: (String -> Void)?
private dynamic func text1Changed(textField: UITextField) {
if enabled {
let text = textField.text ?? ""
self.text1 = text
onText1Changed?(text)
}
}
private dynamic func text2Changed(textField: UITextField) {
if enabled {
let text = textField.text ?? ""
self.text2 = text
onText2Changed?(text)
}
}
}
Contributing
If you're interesting in helping us improve and maintain Former, it is highly encouraged that you fork the repository and submit a pull request with your updates.
If you do chose to submit a pull request, please make sure to clearly document what changes you have made in the description of the PR.
License
Former is available under the MIT license. See the LICENSE file for more info.
Author: ra1028
Source code: https://github.com/ra1028/Former
License: MIT license
#swift
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10 Free Online Resources To Learn Swift Language
Swift is a fast and efficient general-purpose programming language that provides real-time feedback and can be seamlessly incorporated into existing Objective-C code. This is why developers are able to write safer, more reliable code while saving time. It aims to be the best language that can be used for various purposes ranging from systems programming to mobile as well as desktop apps and scaling up to cloud services.
Below here, we list down the 10 best online resources to learn Swift language.
(The list is in no particular order)
#developers corner #free online resources to learn swift language #learn swift #learn swift free #learn swift online free #resources to learn swift #swift language #swift programming
1609999986
Top Swift Development Companies | Top Swift Developers - TopDevelopers.co
A thoroughly researched list of top Swift developers with ratings & reviews to help find the best Swift development companies around the world.
#swift development service providers #best swift development companies #top swift development companies #swift development solutions #top swift developers #swift