JavaScript-Demos/demos/controller-as-directive-angularjs/index.htm at master · gregorycode/JavaScript-Demos · GitHub

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<!doctype html>
<html ng-app="Demo">
<head>
	<meta charset="utf-8" />

	<title>
		Implementing Controller-As Using A Directive In AngularJS 1.0.8
	</title>

	<style type="text/css">

		a[ ng-click ] {
			color: red ;
			cursor: pointer ;
			text-decoration: underline ;
		}

	</style>
</head>
<body>

	<h1>
		Implementing Controller-As Using A Directive In AngularJS 1.0.8
	</h1>

	<!-- NOTE: As vm. -->
	<div ng-controller="AppController" as="vm">

		<p>
			<a ng-click="vm.toggleSections()">Toggle Sections</a>
		</p>

		<div ng-switch="vm.section">

			<!-- NOTE: As vm. -->
			<p
				ng-switch-when="firstSection"
				ng-controller="FirstController" as="vm">

				{{ vm.title }}

			</p>

			<!-- NOTE: As vm. -->
			<p
				ng-switch-when="secondSection"
				ng-controller="SecondController" as="vm">

				{{ vm.title }}

			</p>

		</div>

	</div>


	<!-- Load scripts. -->
	<script type="text/javascript" src="../../vendor/jquery/jquery-2.0.3.min.js"></script>
	<script type="text/javascript" src="../../vendor/angularjs/angular-1.0.8.min.js"></script>
	<script type="text/javascript">

		// Create an application module for our demo.
		var app = angular.module( "Demo", [] );


		// -------------------------------------------------- //
		// -------------------------------------------------- //


		// I control the root of the application.
		app.controller(
			"AppController",
			function() {

				// I represent the currently-selected section.
				this.section = "firstSection";


				// I switch the currently-selected section.
				this.toggleSections = function() {

					this.section = ( this.section === "firstSection" )
						? "secondSection"
						: "firstSection"
					;

				};

			}
		);


		// -------------------------------------------------- //
		// -------------------------------------------------- //


		// I simply demonstrate that the "vm" reference works.
		app.controller(
			"FirstController",
			function() {

				this.title = "First controller, for the win!";

			}
		);

		// I simply demonstrate that the "vm" reference works.
		app.controller(
			"SecondController",
			function() {

				this.title = "Second controller, heck yeah!";

			}
		);


		// -------------------------------------------------- //
		// -------------------------------------------------- //


		// I attempt to implement (some of) the "controller-as" syntax in AngularJS
		// 1.0.8. This treats the related ngController as an item of the "view model"
		// in the HTML.
		// --
		// CAUTION: This does NOT make the scope unavailable in the view-model; it simply
		// augments the scope with a circular reference.
		app.directive(
			"as",
			function() {

				// I copy the ngController instance reference into the scope so that it
				// can be used to reference the Controller inside the View.
				function prelink( scope, element, attributes, controller ) {

					scope[ attributes.as ] = controller;

					// Injecting the controller into the scope is likely to create a
					// circular object reference: Controller -> Scope -> Controller. As
					// such, let's take extra care to try to break up the reference in
					// order to help with garbage collection.
					scope.$on(
						"$destroy",
						function handleDestroyEvent() {

							scope[ attributes.as ] = null;

							// Also, now that we've created a closure, it may be helpful to
							// clear "closed over" variable references.
							scope = element = attributes = controller = null;

						}
					);

				}


				// Return the directive configuration.
				// --
				// NOTE: We are using the "prelink" phase so that the controller reference
				// is available to the linking the phase of the nested directives.
				// --
				// NOTE: ngController runs at priority 500.
				return({
					link: {
						pre: prelink
					},
					priority: 499,
					require: "ngController",
					restrict: "A"
				});

			}
		);

	</script>

</body>
</html>