Zachary Palmer

Zachary Palmer

1562904290

Creating a Modal Dialog in Angular 8 with TypeScript

There are plenty of plugins and libraries out there that include modal windows, in the past I used them myself when I needed to add a modal to a new project. The main issue I have with 3rd party plugins is that they usually contain a lot of features I don’t need which adds unnecessary bloat to my Angular app, so a while ago I took some time to implement a custom modal window to see how difficult it would be and also to remove the magic & mystery I had in my mind about exactly how modals work.

When I finished I was pleasantly surprised at the relatively small amount of code required to implement a custom modal window, most of the modal ‘magic’ is done with a handful of CSS styles (see modal.component.less) while Angular / TypeScript is just used for showing and hiding the modal windows.

Running the Angular 8 Modal Dialog Locally

  1. Install NodeJS and NPM from https://nodejs.org/en/download/.
  2. Download or clone the project source code from https://github.com/cornflourblue/angular-8-custom-modal
  3. Install all required npm packages by running npm install from the command line in the project root folder (where the package.json is located).
  4. Start the application by running npm start from the command line in the project root folder.

NOTE: You can also run the app directly using the Angular CLI command ng serve --open. To do this first install the Angular CLI globally on your system with the command npm install -g @angular/cli.

Adding Custom Modals to Your Angular 8 App

To add modals to your Angular 8 application you’ll need to copy the /src/app/_modal folder and contents from the example project, the folder contains the modal module and associated files, including:

  • modal.model.less - LESS/CSS styles for displaying modal dialogs, this is where the modal “magic” happens.
  • modal.component.html - modal component template that contains the wrapper html for displaying modal dialogs.
  • modal.component.ts - modal component with the logic for displaying modal dialogs.
  • modal.module.ts - modal module that encapsulates the modal component so it can be imported by the app module.
  • modal.service.ts - modal service that can be used by any angular component to open and close modal dialogs.
  • index.ts - barrel file that re-exports the modal module and service so they can be imported using only the folder path instead of the full path to each file, and also enables importing from multiple files with a single import.

Import the Modal Module into your App Module

To make the modal component available to your Angular 8 application you need to add the ModalModule to the imports array of your App Module (app.module.ts). See the app module from the example app below, the modal module is imported on line 5 and added to the imports array of the app module on line 16.

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule } from '@angular/forms';

import { ModalModule } from './_modal';
import { appRoutingModule } from './app.routing';

import { AppComponent } from './app.component';
import { HomeComponent } from './home';
import { TestPageComponent } from './test-page';

@NgModule({
    imports: [
        BrowserModule,
        FormsModule,
        ModalModule,
        appRoutingModule
    ],
    declarations: [
        AppComponent,
        HomeComponent,
        TestPageComponent
    ],
    bootstrap: [AppComponent]
})

export class AppModule { }

Add the tag to pages where you want to display modals

To add a modal dialog to any page simply add the tag along with the content for the modal. You can put any content you like inside the element. You can also update the modal LESS/CSS if you want to change the styles of the modals, e.g to make them smaller or add CSS animation transitions.

IMPORTANT: A unique id is required for each modal on a page, it can be any string e.g. 'custom-modal-1'. The id string is used by the modal service to keep track of each active modal in the angular app, so the service knows which modal to open/close based on the id passed to the modalService.open() and modalService.close() methods e.g. modalService.open('custom-modal-1').

Here is the home component template from the example app (/src/app/home/home.component.html) that contains two modals, each is opened by a button click, and the first modal contains an input text field that allows you to edit the bodyText displayed in the template.


    # Home

    
{{bodyText}}

    Open Modal 1
    Open Modal 2



    # A Custom Modal!

    
Home page text: 

    Close



    # A Tall Custom Modal!

    Close
	

Opening & Closing Angular 8 Modal Dialogs

To open a modal call the modalService.open() method with the id of the modal you want to open, e.g. modalService.open('custom-modal-1'). To close a modal call the modalService.close() method with the id of the modal you want to close, e.g. modalService.close('custom-modal-1').

By default modals are closed on background click, to disable this remove the chunk of code in the modal component (/src/app/_modal/modal.component.ts) located directly below the comment // close modal on background click.

Here is the home component from the example app (/src/app/home/home.component.ts), it contains methods for opening and closing modals (openModal() and closeModal()) that call the corresponding methods of the modal service.

import { Component, OnInit } from '@angular/core';

import { ModalService } from '../_modal';

@Component({ templateUrl: 'home.component.html' })
export class HomeComponent implements OnInit {
    bodyText: string;

    constructor(private modalService: ModalService) { }

    ngOnInit() {
        this.bodyText = 'This text can be updated in modal 1';
    }

    openModal(id: string) {
        this.modalService.open(id);
    }

    closeModal(id: string) {
        this.modalService.close(id);
    }
}	

Breakdown of the Angular 8 Custom Modal Code

Below is a breakdown of the pieces of code used to implement custom modal dialogs in Angular 8 & TypeScript, you don’t need to know the details of how it all works to use the modals in your project, it’s only if you’re interested in the nuts and bolts or if you want to modify the underlying code or behaviour.

LESS/CSS Styles for Angular 8 Modal Dialogs

These are the styles applied to the custom modal dialogs in this example, they could also be used in non-angular projects as it’s just pure LESS/CSS.

I prefixed the modal element and classes with jw- to prevent conflicts with 3rd party css libraries such as Bootstrap.

/* MODAL STYLES
-------------------------------*/
jw-modal {
    /* modals are hidden by default */
    display: none;

    .jw-modal {
        /* modal container fixed across whole screen */
        position: fixed;
        top: 0;
        right: 0;
        bottom: 0;
        left: 0;

        /* z-index must be higher than .jw-modal-background */
        z-index: 1000;
        
        /* enables scrolling for tall modals */
        overflow: auto;

        .jw-modal-body {
            padding: 20px;
            background: #fff;

            /* margin exposes part of the modal background */
            margin: 40px;
        }
    }

    .jw-modal-background {
        /* modal background fixed across whole screen */
        position: fixed;
        top: 0;
        right: 0;
        bottom: 0;
        left: 0;

        /* semi-transparent black  */
        background-color: #000;
        opacity: 0.75;
        
        /* z-index must be below .jw-modal and above everything else  */
        z-index: 900;
    }
}

body.jw-modal-open {
    /* body overflow is hidden to hide main scrollbar when modal window is open */
    overflow: hidden;
}	

Angular 8 Modal Service

The Angular 8 modal service manages the communication that’s required between page components and modal components. It maintains a list of available modals on the page and exposes methods for interacting with those modals.

import { Injectable } from '@angular/core';

@Injectable({ providedIn: 'root' })
export class ModalService {
    private modals: any[] = [];

    add(modal: any) {
        // add modal to array of active modals
        this.modals.push(modal);
    }

    remove(id: string) {
        // remove modal from array of active modals
        this.modals = this.modals.filter(x => x.id !== id);
    }

    open(id: string) {
        // open modal specified by id
        const modal = this.modals.find(x => x.id === id);
        modal.open();
    }

    close(id: string) {
        // close modal specified by id
        const modal = this.modals.find(x => x.id === id);
        modal.close();
    }
}	

Angular 8 Modal Component

The custom modal component is used to add modal windows anywhere in your angular application by using the `` tag. Each modal instance adds itself to the modal service when it loads by calling modalService.add(this) from the ngOnInit Angular lifecycle method, and removes itself from the modal service when it is destroyed by calling modalService.remove(this.id) from the ngOnDestroy Angular lifecycle method.

import { Component, ViewEncapsulation, ElementRef, Input, OnInit, OnDestroy } from '@angular/core';

import { ModalService } from './modal.service';

@Component({ 
    selector: 'jw-modal', 
    templateUrl: 'modal.component.html', 
    styleUrls: ['modal.component.less'],
    encapsulation: ViewEncapsulation.None
})
export class ModalComponent implements OnInit, OnDestroy {
    @Input() id: string;
    private element: any;

    constructor(private modalService: ModalService, private el: ElementRef) {
        this.element = el.nativeElement;
    }

    ngOnInit(): void {
        // ensure id attribute exists
        if (!this.id) {
            console.error('modal must have an id');
            return;
        }

        // move element to bottom of page (just before ) so it can be displayed above everything else
        document.body.appendChild(this.element);

        // close modal on background click
        this.element.addEventListener('click', el => {
            if (el.target.className === 'jw-modal') {
                this.close();
            }
        });

        // add self (this modal instance) to the modal service so it's accessible from controllers
        this.modalService.add(this);
    }

    // remove self from modal service when component is destroyed
    ngOnDestroy(): void {
        this.modalService.remove(this.id);
        this.element.remove();
    }

    // open modal
    open(): void {
        this.element.style.display = 'block';
        document.body.classList.add('jw-modal-open');
    }

    // close modal
    close(): void {
        this.element.style.display = 'none';
        document.body.classList.remove('jw-modal-open');
    }
}	

Angular 8 Modal Component Template

The modal component template contains just a couple of wrapper divs for the modal content and a div for the modal background. The element is replaced by Angular with the contents you set inside the element, this is called Angular content projection.


    
        
    


	

Thanks for reading

If you liked this post, share it with all of your programming buddies!

Follow us on Facebook | Twitter

#angular #typescript #web-development

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Buddha Community

Creating a Modal Dialog in Angular 8 with TypeScript
Clara  Gutmann

Clara Gutmann

1598727360

Angular 8 Updates And Summary of New Features

Angular 8 Updates And Summary of New Features is today’s topic. Angular 8 arrives with an impressive list of changes and improvements including the much-anticipated Ivy compiler as an opt-in feature. You can check out  Angular 7 features and updates if you have not seen yet. In this blog, we have written some articles about  Angular 7 Crud,  Angular 7 Routing,  Angular ngClass,  Angular ngFor.

Angular 8 Updates And Summary

See the following updates.

TypeScript 3.4

Angular 8.0 is now supported TypeScript 3.4, and even requires it, so you will need to upgrade.

You can look at what  TypeScript 3.3 and  TypeScript 3.4 brings on the table on official Microsoft blog.

#angular #typescript #angular 7 crud #angular 7 routing #angular 8

Christa  Stehr

Christa Stehr

1598940617

Install Angular - Angular Environment Setup Process

Angular is a TypeScript based framework that works in synchronization with HTML, CSS, and JavaScript. To work with angular, domain knowledge of these 3 is required.

  1. Installing Node.js and npm
  2. Installing Angular CLI
  3. Creating workspace
  4. Deploying your First App

In this article, you will get to know about the Angular Environment setup process. After reading this article, you will be able to install, setup, create, and launch your own application in Angular. So let’s start!!!

Angular environment setup

Install Angular in Easy Steps

For Installing Angular on your Machine, there are 2 prerequisites:

  • Node.js
  • npm Package Manager
Node.js

First you need to have Node.js installed as Angular require current, active LTS or maintenance LTS version of Node.js

Download and Install Node.js version suitable for your machine’s operating system.

Npm Package Manager

Angular, Angular CLI and Angular applications are dependent on npm packages. By installing Node.js, you have automatically installed the npm Package manager which will be the base for installing angular in your system. To check the presence of npm client and Angular version check of npm client, run this command:

  1. npm -v

Installing Angular CLI

  • Open Terminal/Command Prompt
  • To install Angular CLI, run the below command:
  1. npm install -g @angular/cli

installing angular CLI

· After executing the command, Angular CLI will get installed within some time. You can check it using the following command

  1. ng --version

Workspace Creation

Now as your Angular CLI is installed, you need to create a workspace to work upon your application. Methods for it are:

  • Using CLI
  • Using Visual Studio Code
1. Using CLI

To create a workspace:

  • Navigate to the desired directory where you want to create your workspace using cd command in the Terminal/Command prompt
  • Then in the directory write this command on your terminal and provide the name of the app which you want to create. In my case I have mentioned DataFlair:
  1. Ng new YourAppName

create angular workspace

  • After running this command, it will prompt you to select from various options about the CSS and other functionalities.

angular CSS options

  • To leave everything to default, simply press the Enter or the Return key.

angular setup

#angular tutorials #angular cli install #angular environment setup #angular version check #download angular #install angular #install angular cli

Clara  Gutmann

Clara Gutmann

1598716260

Angular 8 CRUD Example | Angular 8 Tutorial For Beginners

Angular 8 CRUD is a basic operation to learn Angular from scratch. We will learn how to build a small web application that inserts, read data, update and delete data from the database. You will learn how to create a MEAN Stack web application. In this Angular 8 Tutorial Example, you will learn a new framework by building a crud application.

New features of Angular 8

You check out the new features in brief on my  Angular 8 New Features post.

I have designed this Angular 8 CRUD Tutorial, especially for newcomers, and it will help you to up and running with the latest version of Angular, which is right now 8.

#angular #angular 8 #angular 8 crud

Zachary Palmer

Zachary Palmer

1562904290

Creating a Modal Dialog in Angular 8 with TypeScript

There are plenty of plugins and libraries out there that include modal windows, in the past I used them myself when I needed to add a modal to a new project. The main issue I have with 3rd party plugins is that they usually contain a lot of features I don’t need which adds unnecessary bloat to my Angular app, so a while ago I took some time to implement a custom modal window to see how difficult it would be and also to remove the magic & mystery I had in my mind about exactly how modals work.

When I finished I was pleasantly surprised at the relatively small amount of code required to implement a custom modal window, most of the modal ‘magic’ is done with a handful of CSS styles (see modal.component.less) while Angular / TypeScript is just used for showing and hiding the modal windows.

Running the Angular 8 Modal Dialog Locally

  1. Install NodeJS and NPM from https://nodejs.org/en/download/.
  2. Download or clone the project source code from https://github.com/cornflourblue/angular-8-custom-modal
  3. Install all required npm packages by running npm install from the command line in the project root folder (where the package.json is located).
  4. Start the application by running npm start from the command line in the project root folder.

NOTE: You can also run the app directly using the Angular CLI command ng serve --open. To do this first install the Angular CLI globally on your system with the command npm install -g @angular/cli.

Adding Custom Modals to Your Angular 8 App

To add modals to your Angular 8 application you’ll need to copy the /src/app/_modal folder and contents from the example project, the folder contains the modal module and associated files, including:

  • modal.model.less - LESS/CSS styles for displaying modal dialogs, this is where the modal “magic” happens.
  • modal.component.html - modal component template that contains the wrapper html for displaying modal dialogs.
  • modal.component.ts - modal component with the logic for displaying modal dialogs.
  • modal.module.ts - modal module that encapsulates the modal component so it can be imported by the app module.
  • modal.service.ts - modal service that can be used by any angular component to open and close modal dialogs.
  • index.ts - barrel file that re-exports the modal module and service so they can be imported using only the folder path instead of the full path to each file, and also enables importing from multiple files with a single import.

Import the Modal Module into your App Module

To make the modal component available to your Angular 8 application you need to add the ModalModule to the imports array of your App Module (app.module.ts). See the app module from the example app below, the modal module is imported on line 5 and added to the imports array of the app module on line 16.

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule } from '@angular/forms';

import { ModalModule } from './_modal';
import { appRoutingModule } from './app.routing';

import { AppComponent } from './app.component';
import { HomeComponent } from './home';
import { TestPageComponent } from './test-page';

@NgModule({
    imports: [
        BrowserModule,
        FormsModule,
        ModalModule,
        appRoutingModule
    ],
    declarations: [
        AppComponent,
        HomeComponent,
        TestPageComponent
    ],
    bootstrap: [AppComponent]
})

export class AppModule { }

Add the tag to pages where you want to display modals

To add a modal dialog to any page simply add the tag along with the content for the modal. You can put any content you like inside the element. You can also update the modal LESS/CSS if you want to change the styles of the modals, e.g to make them smaller or add CSS animation transitions.

IMPORTANT: A unique id is required for each modal on a page, it can be any string e.g. 'custom-modal-1'. The id string is used by the modal service to keep track of each active modal in the angular app, so the service knows which modal to open/close based on the id passed to the modalService.open() and modalService.close() methods e.g. modalService.open('custom-modal-1').

Here is the home component template from the example app (/src/app/home/home.component.html) that contains two modals, each is opened by a button click, and the first modal contains an input text field that allows you to edit the bodyText displayed in the template.


    # Home

    
{{bodyText}}

    Open Modal 1
    Open Modal 2



    # A Custom Modal!

    
Home page text: 

    Close



    # A Tall Custom Modal!

    Close
	

Opening & Closing Angular 8 Modal Dialogs

To open a modal call the modalService.open() method with the id of the modal you want to open, e.g. modalService.open('custom-modal-1'). To close a modal call the modalService.close() method with the id of the modal you want to close, e.g. modalService.close('custom-modal-1').

By default modals are closed on background click, to disable this remove the chunk of code in the modal component (/src/app/_modal/modal.component.ts) located directly below the comment // close modal on background click.

Here is the home component from the example app (/src/app/home/home.component.ts), it contains methods for opening and closing modals (openModal() and closeModal()) that call the corresponding methods of the modal service.

import { Component, OnInit } from '@angular/core';

import { ModalService } from '../_modal';

@Component({ templateUrl: 'home.component.html' })
export class HomeComponent implements OnInit {
    bodyText: string;

    constructor(private modalService: ModalService) { }

    ngOnInit() {
        this.bodyText = 'This text can be updated in modal 1';
    }

    openModal(id: string) {
        this.modalService.open(id);
    }

    closeModal(id: string) {
        this.modalService.close(id);
    }
}	

Breakdown of the Angular 8 Custom Modal Code

Below is a breakdown of the pieces of code used to implement custom modal dialogs in Angular 8 & TypeScript, you don’t need to know the details of how it all works to use the modals in your project, it’s only if you’re interested in the nuts and bolts or if you want to modify the underlying code or behaviour.

LESS/CSS Styles for Angular 8 Modal Dialogs

These are the styles applied to the custom modal dialogs in this example, they could also be used in non-angular projects as it’s just pure LESS/CSS.

I prefixed the modal element and classes with jw- to prevent conflicts with 3rd party css libraries such as Bootstrap.

/* MODAL STYLES
-------------------------------*/
jw-modal {
    /* modals are hidden by default */
    display: none;

    .jw-modal {
        /* modal container fixed across whole screen */
        position: fixed;
        top: 0;
        right: 0;
        bottom: 0;
        left: 0;

        /* z-index must be higher than .jw-modal-background */
        z-index: 1000;
        
        /* enables scrolling for tall modals */
        overflow: auto;

        .jw-modal-body {
            padding: 20px;
            background: #fff;

            /* margin exposes part of the modal background */
            margin: 40px;
        }
    }

    .jw-modal-background {
        /* modal background fixed across whole screen */
        position: fixed;
        top: 0;
        right: 0;
        bottom: 0;
        left: 0;

        /* semi-transparent black  */
        background-color: #000;
        opacity: 0.75;
        
        /* z-index must be below .jw-modal and above everything else  */
        z-index: 900;
    }
}

body.jw-modal-open {
    /* body overflow is hidden to hide main scrollbar when modal window is open */
    overflow: hidden;
}	

Angular 8 Modal Service

The Angular 8 modal service manages the communication that’s required between page components and modal components. It maintains a list of available modals on the page and exposes methods for interacting with those modals.

import { Injectable } from '@angular/core';

@Injectable({ providedIn: 'root' })
export class ModalService {
    private modals: any[] = [];

    add(modal: any) {
        // add modal to array of active modals
        this.modals.push(modal);
    }

    remove(id: string) {
        // remove modal from array of active modals
        this.modals = this.modals.filter(x => x.id !== id);
    }

    open(id: string) {
        // open modal specified by id
        const modal = this.modals.find(x => x.id === id);
        modal.open();
    }

    close(id: string) {
        // close modal specified by id
        const modal = this.modals.find(x => x.id === id);
        modal.close();
    }
}	

Angular 8 Modal Component

The custom modal component is used to add modal windows anywhere in your angular application by using the `` tag. Each modal instance adds itself to the modal service when it loads by calling modalService.add(this) from the ngOnInit Angular lifecycle method, and removes itself from the modal service when it is destroyed by calling modalService.remove(this.id) from the ngOnDestroy Angular lifecycle method.

import { Component, ViewEncapsulation, ElementRef, Input, OnInit, OnDestroy } from '@angular/core';

import { ModalService } from './modal.service';

@Component({ 
    selector: 'jw-modal', 
    templateUrl: 'modal.component.html', 
    styleUrls: ['modal.component.less'],
    encapsulation: ViewEncapsulation.None
})
export class ModalComponent implements OnInit, OnDestroy {
    @Input() id: string;
    private element: any;

    constructor(private modalService: ModalService, private el: ElementRef) {
        this.element = el.nativeElement;
    }

    ngOnInit(): void {
        // ensure id attribute exists
        if (!this.id) {
            console.error('modal must have an id');
            return;
        }

        // move element to bottom of page (just before ) so it can be displayed above everything else
        document.body.appendChild(this.element);

        // close modal on background click
        this.element.addEventListener('click', el => {
            if (el.target.className === 'jw-modal') {
                this.close();
            }
        });

        // add self (this modal instance) to the modal service so it's accessible from controllers
        this.modalService.add(this);
    }

    // remove self from modal service when component is destroyed
    ngOnDestroy(): void {
        this.modalService.remove(this.id);
        this.element.remove();
    }

    // open modal
    open(): void {
        this.element.style.display = 'block';
        document.body.classList.add('jw-modal-open');
    }

    // close modal
    close(): void {
        this.element.style.display = 'none';
        document.body.classList.remove('jw-modal-open');
    }
}	

Angular 8 Modal Component Template

The modal component template contains just a couple of wrapper divs for the modal content and a div for the modal background. The element is replaced by Angular with the contents you set inside the element, this is called Angular content projection.


    
        
    


	

Thanks for reading

If you liked this post, share it with all of your programming buddies!

Follow us on Facebook | Twitter

#angular #typescript #web-development

Roberta  Ward

Roberta Ward

1593184320

Basics of Angular: Part-1

What is Angular? What it does? How we implement it in a project? So, here are some basics of angular to let you learn more about angular.

Angular is a Typescript-based open-source front-end web application platform. The Angular Team at Google and a community of individuals and corporations lead it. Angular lets you extend HTML’s syntax to express your apps’ components clearly. The angular resolves challenges while developing a single page and cross-platform applications. So, here the meaning of the single-page applications in angular is that the index.html file serves the app. And, the index.html file links other files to it.

We build angular applications with basic concepts which are NgModules. It provides a compilation context for components. At the beginning of an angular project, the command-line interface provides a built-in component which is the root component. But, NgModule can add a number of additional components. These can be created through a template or loaded from a router. This is what a compilation context about.

What is a Component in Angular?

Components are key features in Angular. It controls a patch of the screen called a view. A couple of components that we create on our own helps to build a whole application. In the end, the root component or the app component holds our entire application. The component has its business logic that it does to support the view inside the class. The class interacts with the view through an API of properties and methods. All the components added by us in the application are not linked to the index.html. But, they link to the app.component.html through the selectors. A component can be a component and not only a typescript class by adding a decorator @Component. Then, for further access, a class can import it. The decorator contains some metadata like selector, template, and style. Here’s an example of how a component decorator looks like:

@Component({
    selector: 'app-root',
    templateUrl: 'app.component.html',
    styleUrls: ['app.component.scss']
})

Role of App Module

Modules are the package of functionalities of our app. It gives Angular the information about which features does my app has and what feature it uses. It is an empty Typescript class, but we transform it by adding a decorator @NgModule. So, we have four properties that we set up on the object pass to @NgModule. The four properties are declarations, imports, providers, and bootstrap. All the built-in new components add up to the declarations array in @NgModule.

@NgModule({
declarations: [
  AppComponent,
],
imports: [
  BrowserModule,
  HttpClientModule,
  AppRoutingModule,
  FormsModule
],
bootstrap: [AppComponent]
})

What is Data Binding?

Data Binding is the communication between the Typescript code of the component and the template. So, we have different kinds of data binding given below:

  • When there is a requirement to output data from our Typescript code in the HTML template. String interpolation handles this purpose like {{data}} in HTML file. Property Binding is also used for this purpose like [property] = “data”.
  • When we want to trigger any event like clicking a button. Event Binding works while we react to user events like (event) = “expression”.
  • When we can react to user events and output something at the same time. Two-way Binding is used like [(ngModel)] = “data”.

image for understanding data binding

#angular #javascript #tech blogs #user interface (ui) #angular #angular fundamentals #angular tutorial #basics of angular