Angular
Introduction
Angular Versions
- Angular 1.0 is the old version of angular along with AngularJS
- Angular, starts at 2 and skips 3 and is now at 9 is the version this page is about
Benefits
- Compiles with ES6
- Use modules
- Built in Internationalisation and Accessibility
- Comes with Router, http, forms, rxjs, etc
- Supports Progress Web Apps, (Mobile, Web like React)
- Server-side rendering (render page on server)
- One-way data flow (like React update from parent down)
- Dependency injection
- Uses zone.js to detect change before rendering
- Like React, multiple rendering targets, Browser/DOM, Server Side, Mobile Apps, Desktops
Angular CLI
When we build JavaScript we have to manage
- Module Handling
- Minifying
- Shims (compatibility to legacy code)
- Zone.js wrapper
- Bundling
- Transpilation, compiling to ESx (babel)
Then Angular CLI can
- Create new application
- New components/service/pipe
- Serve up the Application
- Linting
- Testing
- Building
Sample App
This is the sample app I built
The files for the example can be found at [1]
Components
Introduction
Components comprise of
- Template
- Class
- Metadata
Starting the App
Here is the index.html which has the pm-root tag inside it to denote a component.
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>APM</title>
<base href="/">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="icon" type="image/x-icon" href="favicon.ico">
</head>
<body>
<pm-root></pm-root>
</body>
</html>
Here is a sample app.module (possibly main) used.
import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { AppComponent } from './app.component';
@NgModule({
declarations: [
AppComponent
],
imports: [
BrowserModule
],
bootstrap: [AppComponent]
})
export class AppModule { }
And finally the component we defined.
import { Component } from '@angular/core';
@Component({
selector: 'pm-root',
template: `
<div>
<h1>{{pageTitle}}</h1>
<div>My First Component</div>
</div>
`
})
export class AppComponent {
pageTitle: string = 'Angular: Getting Started 2';
}