Angular Basics

Welcome back everyone! This course is designed specifically for beginners to learn Angular. We'll cover fundamentals, explore new features, and build practical projects. This is part of a comprehensive series.

Introduction to Web Development

• Two Sides in Web Development
  • Front End (Client Side): Loads in the browser and handles user interactions.
  • Back End (Server Side): Loads in the server and handles data responses.

Traditional Front End Development

• HTML: Builds the structure of web pages.
• CSS: Makes web pages user-friendly with colors, fonts, and layouts.
• JavaScript: Adds functionality to web pages (e.g., DOM manipulation, events).
  • DOM Manipulation: Document Object Model management using JavaScript.

Emergence of Front End Frameworks

• Challenges with Vanilla JavaScript: Buggy and time-consuming DOM manipulation.
• Google and Meta Solutions:
  • Angular: A front-end framework built using JavaScript, developed by Google.
  • React: Another front-end library by Meta.

Understanding Angular

• Key Points:
  • Not a new programming language, built on JavaScript.
  • Improves and speeds up the developer experience.
  • Uses standard web technologies (HTML, CSS, JavaScript) with syntax enhancements.
• SPA (Single Page Applications):
  • Definition: Apps that don’t reload during views and work within a browser.
  • Examples: Facebook, Google Maps, Gmail, Twitter, Google Drive, GitHub.
  • Benefits: Responsive, no constant wait for client-server communication.

Setting Up Angular Environment

• Angular CLI: Command Line Interface tool for Angular.
• Installing Angular CLI:
  1. Install Node Package Manager (NPM) bundled with Node.js.
  2. Run npm install -g @angular/cli to install Angular CLI globally.
• Generating Angular Application:
  • Initialize using ng new <project-name>.
  • Example: ng new my-app.

Angular Components

• Component Design:
  • Central part of Angular applications.
  • Each component represents a part of the view with its own template, style, and logic.
• Creating Components:
  • Manual method: Create TypeScript, HTML, and CSS files, import necessary modules.
  • Using Angular CLI: ng generate component <component-name>.
  • Benefits: Reusability and maintainability.

Data Binding

• Types of Data Binding:
  • String Interpolation: Embedding dynamic values in an HTML template.
  • Property Binding: Binding DOM properties to component properties.
  • Class Binding: Dynamically add or remove CSS classes.
  • Style Binding: Dynamically bind styles to elements.
  • Event Binding: Handling events like clicks or keypresses.
  • Two-way Binding: Sync data between the view and component in both directions using [(ngModel)].

Directives in Angular

• Types of Directives:
  • Component Directives: Angular components themselves.
  • Structural Directives: Alter the layout by adding/removing DOM elements (e.g., *ngIf, *ngFor, *ngSwitch).
  • Attribute Directives: Change appearance/behavior of an element (e.g., ngClass, ngStyle).
• Structural Directives Examples:
  • *ngIf: Conditionally include/exclude elements based on a boolean value.
  • *ngFor: Repeat an HTML element for each item in a collection.
  • ngSwitch and ngSwitchCase: Display one of many elements based on a matching criterion.

Advanced Angular Features

• Handling Arrays and Objects:
  • Using *ngFor to loop through arrays.
  • Differentiating between arrays of primitives and objects.
  • Using index and trackBy with *ngFor for better performance.
• Angular Change Detection:
  • Angular automatically detects changes and updates the DOM.
  • Example: Adding/deleting items in a list in real-time without page refresh.
• ng-template:
  • Define template blocks for later use.
  • Not rendered in the DOM until called explicitly.
  • Useful for reusable code snippets or complex dynamic templates.

Conclusion

• Recap: We covered the fundamentals of Angular, discussed its core concepts such as components and directives, explored different types of data binding, and briefly introduced advanced topics like handling arrays, change detection, and ng-template.
• Next Steps: Stay tuned for in-depth lessons and exciting challenges to master advanced Angular features.