angular js - introduction
TRANSCRIPT
HTML enhanced for web apps!~Sagar Acharya
Agenda• Misunderstandings • What is angular?• SPAs• Why angular?• Features• MVC/MVVM• Directives, filters, expression• Demo • Why should we use it?• Why developer should use it?• Stats
Another JS Lib
Lots of new learning
Difficult to learn
Useful for web only ?Used for
styling purpose
What is ANGULARJS?
• It’s not a JavaScript library (As they say). There are no functions which we can directly call and use.
• It is not a DOM manipulation library like jQuery. But it uses subset of jQuery for DOM manipulation (called jqLite).
What is ANGULAR JS? (contd…)
• Focus more on HTML side of web apps.
• For MVC/MVVM design pattern
• AngularJS is a Javascript MVC framework created by Google to build properly architectured and maintenable web applications.
• “ANGULARJS is what HTML could have been if it had been designed for web application development.”
• AngularJS extends HTML with new attributes.
Single Page Application (SPA)SPA Demo
http://www.myspa.com
View View
View View
The Challenge with SPAs
DOM Manipulation History
Routing
Module Loading
Data Binding
Object Modeling
Ajax/Promises
Caching
View Loading
Solution?
Why ANGULARJS?• Defines numerous ways to organize web application at client side.
• Enhances HTML by attaching directives, custom tags, attributes, expressions, templates within HTML.
• Encourage TDD
• Encourage MVC/MVVM design pattern
• Code Reuse
• Good for Single Page Apps (SPA)
• Cool Features -> Next Slide
Key Features of ANGULARJS
ngularJS is a full-featured SPA framework
Data Binding MVC Routing
Templates
ViewModel Views
Controllers Dependency Injection
Directives
Testing
Controllers
jqLite
Validation
FactoriesHistory
MVC : Model View Controller
View
ControllerModel
1. Event or User Action or View Load
2. Maps to particular Model after fetching the data
3. Implement the Business Logic on response data and Bind it to View
View : • Renders the Model data• Send User actions/events to
controller• UI
Controller: • Define Application Behavior• Maps user actions to Model• Select view for response
Model: • Business Logic• Notify view changes• Application
Functionality• Data in general
MVVM: Model View ViewModel
View
ViewModelModel
UI
Presentation LogicBusiness Logic and Data
• User actions, commands• Data binding• Notifications
• Data Access• Update ViewModel about
change
What are Directives?
• The directives can be placed in element names, attributes, class names, as well as comments. Directives are a way to teach HTML new tricks.
• A directive is just a function which executes when the compiler encounters it in the DOM.
• <input ng-model='name'>
• Custom Defined Directives
• <span draggable>Drag ME</span>
What are Directives? (contd..)
<!DOCTYPE html><html ng-app><head> <title></title></head><body> <div class="container"> Name: <input type="text" ng-model="name" /> {{ name }} </div>
<script src="Scripts/angular.js"></script></body></html>
Directive
Directive
Data Binding Expression
Iterating with ng-repeat Directive<html data-ng-app="">...
<div class="container" data-ng-init="names=['Dave','Napur','Heedy','Shriva']">
<h3>Looping with the ng-repeat Directive</h3> <ul> <li data-ng-repeat="name in names">{{ name }}</li> </ul> </div>
...</html>
Iterate through names
Filters
Angular filters format data for display to the user.
{{ expression [| filter_name[:parameter_value] ... ] }}
{{ uppercase_expression | uppercase }}
{{ expression | filter1 | filter2 }}
Can create custom filters
Using Filters
<ul> <li data-ng-repeat="cust in customers | orderBy:'name'"> {{ cust.name | uppercase }} </li></ul>
Order customers by name property
<input type="text" data-ng-model="nameText" /><ul> <li data-ng-repeat="cust in customers | filter:nameText | orderBy:'name'"> {{ cust.name }} - {{ cust.city }}</li></ul>
Filter customers by model value
Expression
Expressions are JavaScript-like code snippets that are usually placed in bindings such as {{ expression }}
<body>
1+2={{1+2}}
</body>
Demo
Why should we use Angular JS?
• Bootstrap features
• Directives for animation & effects for interactive UI
• SPA : modern way to represent WEB APP
• Compatible with mobile app development
Why Developer should use Angular JS?
• It is developed by google.
• RESTful actions (Using one line of JS you can quickly communicate with server)
• Dependency Injection (DI) is a software design pattern that deals with how components get hold of their dependencies.
• Provides several options for testing (TDD)
• Flexibility with filters
• Good documentation & resources.
Some Statistics!
o Angular JS is 3 times faster than any external JS available till now ~Google.
More Statistics! (Interesting One)• GITHUB Stats:
• Stars:o if you star a repository, you basically want to show your appreciation as well as
keep track of repositories that you find interesting without it spamming your timeline.
o In top 3 of github stars project list, only bootstrap & node js is ahead of it.o Check stars stats:o https://github.com/search?utf8=%E2%9C%93&q=stars%3A%3E30000&type=Repos
itories&ref=searchresults• fork:
o In software engineering, a project fork happens when developers take a legal copy of source code from one software package and start independent development on it, creating a distinct piece of software.
o In top 7 of github fork project list.o Check fork stats:o https://github.com/search?utf8=%E2%9C%93&q=forks%3A%3E10000&type=Repos
itories&ref=searchresults
Resources
Documentation
• AngularJS Developer Guide
• AngularJS API
• AngularJS Tutorial
Videos
• AngularJS Fundamentals In 60-ish Minutes
• Introduction to Angular JS
• AngularJS end-to-end web app tutorial Part I
