Karim Aya

Karim Aya

1554263984

Angular Directives Tutorial

In this post, we go over three popular directive in Angular and show you how to implement them in your code.

A directive is an add-on or an extension to Angular features, used for optimizing your reusable code.

There are three types of directives in Angular (component, attribute, and structural).

Component Directives

A component is a directive with a template. Basically, whatever we do in Angular is a component. It is a reusable part of the whole application.

Here is an example of a simple animation component that rotates the div by 180 degrees when clicked.

Template:

<div (click)="animateDiv(animatediv)" #animatediv class="animateDiv">CLICK ME</div>

TS file:

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

@Component({

  selector: ‘app-animation’,

  templateUrl: ‘./animation.component.html’,

  styleUrls: [‘./animation.component.css’]

})

export class AnimationComponent implements OnInit {

  constructor() { }

public animateDiv(receivedObj){

 receivedObj.style.;

  }

}

Attribute Directives

An attribute directive changes the way a component, element, or directive looks. Attribute directives are used to give a better look and feel to our element. Some of the commonly used attribute directives in Angular are: ngStylengSwitchngModelngClass.

Below is an example of a simple component showing how to use the ngStyle irectived. It assigns the background color as blue if the item is a fruit and green if it is a vegetable.

<ul *ngFor=“let item of items”>
  <li class=“item” [ngStyle]=“{‘backgroundColor’:getBgColor(item.type)}” >
{{ item.name
</li>
</ul>
export class ItemsComponent {

  public items = [

    {id:1,name:‘APPLE’,type:‘fruit’},

    {id:1,name:‘TURNIP’,type:‘vegetable’},

    {id:1,name:‘ORANGE’,type:‘fruit’}

  ];

  public getBgColor(type){

    if(type == ‘fruit’){

      return ‘blue’;

    }else{

      return ‘green’;

    }

  }

}

Structural Directives

As the name suggests, a structural directive changes the structure of a component, element, or directive. Basically, it is used to manipulate the DOM. Some of the commonly used structural directives in Angular are ngIf and ngFor.

Below is a simple component showing the usage of the ngIf directive. This component toggles the div on the click of the button.

Template:

<button (click)>TOGGLE</button>

<div class=“showDiv” *>I AM VISIBLE</div>

TS file:

export class ToggleComponent {

public showDiv:boolean = true; 

public toggleDiv(){

  this.showDiv = !this.showDiv;

}

}

Building Custom Directives

We can also create custom directives based on our requirements and use them throughout the application.

Example

Template:

<p appPaintGreen>I AM A GREEN PARAGRAPH</p>

TS File:

import { Directive, ElementRef } from ‘@angular/core’;

@Directive({

  selector: ‘[appPaintGreen]’

})

export class PaintGreenDirective {

  constructor(private el:ElementRef) {

    // el here contains the object in which you are using this directive

    el.nativeElement.style.backgroundColor = ‘green’;

    el.nativeElement.;

  }

}

Conclusion

Directives are basically custom elements that give some extra capability to an element. They can be used based to make our components flexible in both appearance and functionality.

Originally published by Mamatamayee parida at https://dzone.com

Learn More

☞ Angular 7 (formerly Angular 2) - The Complete Guide

☞ Learn and Understand AngularJS

☞ Angular Crash Course for Busy Developers

☞ The Complete Angular Course: Beginner to Advanced

☞ Angular (Angular 2+) & NodeJS - The MEAN Stack Guide

☞ Become a JavaScript developer - Learn (React, Node,Angular)

☞ Angular (Full App) with Angular Material, Angularfire & NgRx

☞ The Web Developer Bootcamp

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Angular Directives Tutorial
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

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

akshay L

akshay L

1613737472

Angular Tutorial | Angular Tutorial For Beginners | Angular Training | Intellipaat

In this Angular tutorial you will learn what is angular, angular architecture, what is typescript, Data binding & interpolation, angular components, Variable Declaration & Function Declaration, Encapsulation & Polymorphism in Angular, Angular Routing and Navigation, various angular basic & advanced concepts, hands-on demo on how to import & export data in angular, Angular JS vs Angular vs React JS and angular CLI among others.

#angular tutorial #angular tutorial for beginners #angular training

Salman Ahmad

1588747755

Deploy Angular 10/9 App to Production with Firebase Hosting

In this tutorial, I am going to share with you How to Deploy Angular 10/9 App to Production with Firebase Hosting?.

#angular #firebase #popular tutorials #angualr firebase deploy #angular app #angular tutorial #firebase tutorial

Ayyaz Zafar

1624138795

Angular Material Autocomplete - Multiple Use Cases covered

Learn How to use Angular Material Autocomplete Suggestions Search Input. I covered multiple use cases.

Please watch this video. I hope this video would be helpful for you to understand it and use it in your projects

Please subscribe: https://www.youtube.com/channel/UCL5nKCmpReJZZMe9_bYR89w

#angular #angular-material #angular-js #autocomplete #angular-material-autocomplete #angular-tutorial