Anuradha Bandara

How Web Page Creates?
 HTML (Structure)
 Css (Style)
 Javascript (Behavior)
◦ HTML tags create objects.
 In other words……Document Object Model(DOM)
◦ <SCRIPT></SCRIPT>
 Once page found this tag – Start download the javascript.
◦ JavaScript lets you manipulate the DOM.
◦ Css – do the styles.

What is DOM?
 The Document Object Model (DOM) is an application programming
interface (API) for valid HTML and well-formed XML documents. It
defines the logical structure of documents and the way a document
is accessed and manipulated.

DOM Structure

DOM Structure

What is Angularjs?
 A JavaScript framework for creating
dynamic web applications
 Open Source
◦ GitHub:
https://github.com/angular/angular.js
◦ MIT License
 Uses jQuery
◦ jQuery 1.7.1 or above
◦ jQLite

MVC or MVW….
 Model
◦ The data
 View
◦ The interface
◦ How the data is presented to the user
 Whatever
(Controller/Services/Directives/Filters)
◦ The behavior
◦ Modifying / updating the models

How Angularjs works?
 bindJQuery() : Either one of jQuery or jqLite is bound to angular.
 angularInit(document, bootstrap) : method which checks for ng-app module
 bootstrap(element) : method which is invoked once an ng-app module is found
◦ Invoke createInjector() method which returns dependency injector
◦ The dependency injector invokes the compilation and linking process with some of the following
key parameters:
 Scope object – Reference to rootScope
 Reference to element with ng-app
 Compile service
 Reference to dependency injector

How Angularjs works? Cont…
 compile(element): bind events to the element
 compile(element)(scope): bind element to the scope
◦ At this phase compiler will look for every directive and creates the watchers ($watch) that are
needed.
 scope.$apply(function{}): Finally, the $apply method is invoked on
the scope object
As a result of execution of $apply
method, the view appears……

How Angularjs works? Cont…

Reusable components with
directives….
 A directive is an extension of the HTML vocabulary that allows us to
create new behaviours. This technology lets the developers create
reusable components that can be used within the whole application.
 The directive can be applied as an
◦ Attribute
◦ Element
◦ Class
◦ Comment
 we can use ng-model, ng:model, ng_model,data-ng-model,
and x-ng-model in the HTML markup.

AngularJS built-in directives...
 ngApp - defines the root of an AngularJS application
 ngController - attach any controller to the view
◦ Nested Controllers
 ngBind – act as same as {{expression}}
 ngBindHtml – bind plain html

AngularJS built-in directives...
 ngRepeat - iterate over arrays and objects.
 ngModel - attaches the element to a property in
the scope
 ngClick – bind any custom behavior to the click
event of the element
 ngDisable – disable elements based on the
Boolean value of an expression.
 ngClass – dynamically apply a class to an element
 ngOptions – create the options of a select element
 ngStyle – apply the dynamic style configuration
demand

AngularJS built-in directives...
 ngShow/ngHide – apply visibility of an element
based on its
display property.
 ngIf - prevents the rendering of an element in our template
 ngClick – bind any custom behavior to the click
event of the element
 ngInclude – include other external HTML fragments in to
pages

Create own Directory
Directive properties

Dependency Injection
and Services…
 Services
◦ Use to isolating the business logic in the application
 Lazily instantiated – Angular only instantiates a service when an application component depends on it.
 Singletons – Each component dependent on a service gets a reference to the single instance generated
by the service factory.
 No UI
 Dependency Injection
◦ A software design pattern that deals with how components get hold of
their dependencies.
◦ eg :

Dependency Injection
and Services…
 Custom Services
◦ We can define our own custom services in different ways in angular js app
and use them wherever required
 Service()
 Factory()
 Provider()

Dependency Injection
and Services…
 Creating services with the factory
◦ You give angular a function
◦ Angular create an object
◦ add properties to it
◦ return that same object

Dependency Injection
and Services…
 Creating services with the Service
◦ You give angular a function
◦ Angular will instantiated with the ‘new’ keyword
◦ add properties to “this”
◦ return “this”

Dependency Injection
and Services…
 Creating services with the Provider
◦ You give angular a function
◦ angular will call its $get function
◦ return value from the $get function

Data handling…
 Expressions
 Filters
 Form validations

Data handling…
 Expressions
◦ An expression is a simple piece of code
that will be evaluated by the framework
and can be written between double curly
brackets
eg : {{car.plate}}

Data handling…
 Filters
◦ perfect solution to easily perform any data manipulation.
 Eg :
 {{expression | filter}}
 {{expression | filter1 | filter2}}
◦ Currency
 {{ 10 | currency}} => $10.00 (take locale currency)
 {{ 10 | currency:'R$'}} => R$ 10.00
◦ Date
 {{ car.entrance | date }} => Dec 10, 2014
 {{ car.entrance | date:'MMMM dd/MM/yyyy HH:mm:ss' }} =>
December 10/12/2013 21:42:10.

Data handling…
 Filters
◦ Filter
◦ Json
 {{ car | json }} =>

Data handling…
 Filters
◦ limitTo – limit size to 10
 {{ expression | limitTo:10 }}
◦ Lowercase – convert to lowercase
 {{ expression | lowercase }}
◦ Number – limit two decimal places
 {{ 10 | number:2 }} => 10.00
◦ Orderby – orderby String/Array
 {{ expression | orderBy:predicate:reverse }}

Data handling…
 Creating custom filters

Data handling…
 Form validations
 $pristine =>form is not modified
 $dirty => form is modified

Data handling…
 Form validations
 $error => It accumulates the detailed list of
everything that happens with the form

Data Binding – Two way
 Data-binding in Angular apps is the automatic synchronization of
data between the model and view components.
 The view is a projection of the model at all times. When the model
changes, the view reflects the change, and vice versa.

How Data binding works?
Exactly what happen when you do event on a
browser….
 browser is waiting for events / user interactions.
 click on a button or write into an input.
 fire browser event loop.
 browser will make the appropriate changes in the DOM

How Data binding works?
How angulerjs reacts?
 When you create ui component using directive
 Add $watch to watch list call $digest
 After fire event loop $digest loop will be fired.
 It checks values are updated.
 Call $apply()
As a result of execution of $apply method, the view
updated……

Scope….
 scope is an object that refers to the application model
 Scopes are arranged in hierarchical structure which mimic the DOM
structure of the application
 Create connection between view & controller

$rootscope / $parent / $scope
You give angular a functionYou give angular a function

Exercise..
 Writing own directory…
◦ Replace label with dropdown when click
the edit button.
◦ When user change the dropdown
automatically update the model.

Thank you….