mirror of
https://github.com/Hopiu/angular.js.git
synced 2026-03-17 07:40:22 +00:00
790 lines
30 KiB
JavaScript
790 lines
30 KiB
JavaScript
'use strict';
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/**
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* DESIGN NOTES
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*
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* The design decisions behind the scope ware heavily favored for speed and memory consumption.
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*
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* The typical use of scope is to watch the expressions, which most of the time return the same
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* value as last time so we optimize the operation.
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*
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* Closures construction is expensive from speed as well as memory:
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* - no closures, instead ups prototypical inheritance for API
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* - Internal state needs to be stored on scope directly, which means that private state is
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* exposed as $$____ properties
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*
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* Loop operations are optimized by using while(count--) { ... }
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* - this means that in order to keep the same order of execution as addition we have to add
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* items to the array at the begging (shift) instead of at the end (push)
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*
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* Child scopes are created and removed often
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* - Using array would be slow since inserts in meddle are expensive so we use linked list
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*
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* There are few watches then a lot of observers. This is why you don't want the observer to be
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* implemented in the same way as watch. Watch requires return of initialization function which
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* are expensive to construct.
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*/
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/**
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* @ngdoc object
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* @name ng.$rootScopeProvider
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* @description
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*
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* Provider for the $rootScope service.
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*/
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/**
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* @ngdoc function
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* @name ng.$rootScopeProvider#digestTtl
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* @methodOf ng.$rootScopeProvider
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* @description
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*
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* Sets the number of digest iteration the scope should attempt to execute before giving up and
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* assuming that the model is unstable.
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*
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* The current default is 10 iterations.
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*
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* @param {number} limit The number of digest iterations.
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*/
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/**
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* @ngdoc object
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* @name ng.$rootScope
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* @description
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*
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* Every application has a single root {@link ng.$rootScope.Scope scope}.
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* All other scopes are child scopes of the root scope. Scopes provide mechanism for watching the model and provide
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* event processing life-cycle. See {@link guide/scope developer guide on scopes}.
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*/
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function $RootScopeProvider(){
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var TTL = 10;
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this.digestTtl = function(value) {
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if (arguments.length) {
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TTL = value;
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}
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return TTL;
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};
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this.$get = ['$injector', '$exceptionHandler', '$parse',
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function( $injector, $exceptionHandler, $parse) {
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/**
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* @ngdoc function
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* @name ng.$rootScope.Scope
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*
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* @description
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* A root scope can be retrieved using the {@link ng.$rootScope $rootScope} key from the
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* {@link AUTO.$injector $injector}. Child scopes are created using the
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* {@link ng.$rootScope.Scope#$new $new()} method. (Most scopes are created automatically when
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* compiled HTML template is executed.)
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*
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* Here is a simple scope snippet to show how you can interact with the scope.
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* <pre>
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angular.injector(['ng']).invoke(function($rootScope) {
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var scope = $rootScope.$new();
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scope.salutation = 'Hello';
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scope.name = 'World';
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expect(scope.greeting).toEqual(undefined);
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scope.$watch('name', function() {
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this.greeting = this.salutation + ' ' + this.name + '!';
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}); // initialize the watch
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expect(scope.greeting).toEqual(undefined);
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scope.name = 'Misko';
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// still old value, since watches have not been called yet
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expect(scope.greeting).toEqual(undefined);
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scope.$digest(); // fire all the watches
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expect(scope.greeting).toEqual('Hello Misko!');
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});
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* </pre>
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*
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* # Inheritance
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* A scope can inherit from a parent scope, as in this example:
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* <pre>
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var parent = $rootScope;
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var child = parent.$new();
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parent.salutation = "Hello";
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child.name = "World";
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expect(child.salutation).toEqual('Hello');
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child.salutation = "Welcome";
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expect(child.salutation).toEqual('Welcome');
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expect(parent.salutation).toEqual('Hello');
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* </pre>
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*
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*
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* @param {Object.<string, function()>=} providers Map of service factory which need to be provided
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* for the current scope. Defaults to {@link ng}.
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* @param {Object.<string, *>=} instanceCache Provides pre-instantiated services which should
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* append/override services provided by `providers`. This is handy when unit-testing and having
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* the need to override a default service.
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* @returns {Object} Newly created scope.
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*
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*/
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function Scope() {
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this.$id = nextUid();
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this.$$phase = this.$parent = this.$$watchers =
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this.$$nextSibling = this.$$prevSibling =
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this.$$childHead = this.$$childTail = null;
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this['this'] = this.$root = this;
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this.$$asyncQueue = [];
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this.$$listeners = {};
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}
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/**
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* @ngdoc property
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* @name ng.$rootScope.Scope#$id
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* @propertyOf ng.$rootScope.Scope
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* @returns {number} Unique scope ID (monotonically increasing alphanumeric sequence) useful for
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* debugging.
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*/
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Scope.prototype = {
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/**
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* @ngdoc function
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* @name ng.$rootScope.Scope#$new
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* @methodOf ng.$rootScope.Scope
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* @function
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*
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* @description
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* Creates a new child {@link ng.$rootScope.Scope scope}.
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*
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* The parent scope will propagate the {@link ng.$rootScope.Scope#$digest $digest()} and
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* {@link ng.$rootScope.Scope#$digest $digest()} events. The scope can be removed from the scope
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* hierarchy using {@link ng.$rootScope.Scope#$destroy $destroy()}.
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*
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* {@link ng.$rootScope.Scope#$destroy $destroy()} must be called on a scope when it is desired for
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* the scope and its child scopes to be permanently detached from the parent and thus stop
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* participating in model change detection and listener notification by invoking.
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*
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* @param {boolean} isolate if true then the scoped does not prototypically inherit from the
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* parent scope. The scope is isolated, as it can not se parent scope properties.
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* When creating widgets it is useful for the widget to not accidently read parent
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* state.
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*
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* @returns {Object} The newly created child scope.
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*
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*/
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$new: function(isolate) {
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var Child,
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child;
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if (isFunction(isolate)) {
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// TODO: remove at some point
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throw Error('API-CHANGE: Use $controller to instantiate controllers.');
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}
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if (isolate) {
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child = new Scope();
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child.$root = this.$root;
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} else {
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Child = function() {}; // should be anonymous; This is so that when the minifier munges
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// the name it does not become random set of chars. These will then show up as class
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// name in the debugger.
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Child.prototype = this;
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child = new Child();
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child.$id = nextUid();
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}
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child['this'] = child;
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child.$$listeners = {};
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child.$parent = this;
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child.$$asyncQueue = [];
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child.$$watchers = child.$$nextSibling = child.$$childHead = child.$$childTail = null;
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child.$$prevSibling = this.$$childTail;
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if (this.$$childHead) {
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this.$$childTail.$$nextSibling = child;
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this.$$childTail = child;
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} else {
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this.$$childHead = this.$$childTail = child;
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}
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return child;
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},
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/**
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* @ngdoc function
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* @name ng.$rootScope.Scope#$watch
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* @methodOf ng.$rootScope.Scope
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* @function
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*
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* @description
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* Registers a `listener` callback to be executed whenever the `watchExpression` changes.
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*
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* - The `watchExpression` is called on every call to {@link ng.$rootScope.Scope#$digest $digest()} and
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* should return the value which will be watched. (Since {@link ng.$rootScope.Scope#$digest $digest()}
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* reruns when it detects changes the `watchExpression` can execute multiple times per
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* {@link ng.$rootScope.Scope#$digest $digest()} and should be idempotent.)
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* - The `listener` is called only when the value from the current `watchExpression` and the
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* previous call to `watchExpression' are not equal (with the exception of the initial run
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* see below). The inequality is determined according to
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* {@link angular.equals} function. To save the value of the object for later comparison
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* {@link angular.copy} function is used. It also means that watching complex options will
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* have adverse memory and performance implications.
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* - The watch `listener` may change the model, which may trigger other `listener`s to fire. This
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* is achieved by rerunning the watchers until no changes are detected. The rerun iteration
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* limit is 100 to prevent infinity loop deadlock.
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*
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*
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* If you want to be notified whenever {@link ng.$rootScope.Scope#$digest $digest} is called,
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* you can register an `watchExpression` function with no `listener`. (Since `watchExpression`,
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* can execute multiple times per {@link ng.$rootScope.Scope#$digest $digest} cycle when a change is
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* detected, be prepared for multiple calls to your listener.)
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*
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* After a watcher is registered with the scope, the `listener` fn is called asynchronously
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* (via {@link ng.$rootScope.Scope#$evalAsync $evalAsync}) to initialize the
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* watcher. In rare cases, this is undesirable because the listener is called when the result
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* of `watchExpression` didn't change. To detect this scenario within the `listener` fn, you
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* can compare the `newVal` and `oldVal`. If these two values are identical (`===`) then the
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* listener was called due to initialization.
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*
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*
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* # Example
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* <pre>
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// let's assume that scope was dependency injected as the $rootScope
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var scope = $rootScope;
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scope.name = 'misko';
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scope.counter = 0;
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expect(scope.counter).toEqual(0);
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scope.$watch('name', function(newValue, oldValue) { counter = counter + 1; });
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expect(scope.counter).toEqual(0);
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scope.$digest();
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// no variable change
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expect(scope.counter).toEqual(0);
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scope.name = 'adam';
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scope.$digest();
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expect(scope.counter).toEqual(1);
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* </pre>
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*
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*
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*
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* @param {(function()|string)} watchExpression Expression that is evaluated on each
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* {@link ng.$rootScope.Scope#$digest $digest} cycle. A change in the return value triggers a
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* call to the `listener`.
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*
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* - `string`: Evaluated as {@link guide/expression expression}
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* - `function(scope)`: called with current `scope` as a parameter.
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* @param {(function()|string)=} listener Callback called whenever the return value of
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* the `watchExpression` changes.
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*
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* - `string`: Evaluated as {@link guide/expression expression}
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* - `function(newValue, oldValue, scope)`: called with current and previous values as parameters.
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*
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* @param {boolean=} objectEquality Compare object for equality rather then for refference.
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* @returns {function()} Returns a deregistration function for this listener.
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*/
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$watch: function(watchExp, listener, objectEquality) {
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var scope = this,
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get = compileToFn(watchExp, 'watch'),
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array = scope.$$watchers,
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watcher = {
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fn: listener,
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last: initWatchVal,
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get: get,
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exp: watchExp,
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eq: !!objectEquality
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};
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// in the case user pass string, we need to compile it, do we really need this ?
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if (!isFunction(listener)) {
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var listenFn = compileToFn(listener || noop, 'listener');
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watcher.fn = function(newVal, oldVal, scope) {listenFn(scope);};
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}
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if (!array) {
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array = scope.$$watchers = [];
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}
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// we use unshift since we use a while loop in $digest for speed.
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// the while loop reads in reverse order.
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array.unshift(watcher);
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return function() {
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arrayRemove(array, watcher);
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};
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},
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/**
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* @ngdoc function
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* @name ng.$rootScope.Scope#$digest
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* @methodOf ng.$rootScope.Scope
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* @function
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*
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* @description
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* Process all of the {@link ng.$rootScope.Scope#$watch watchers} of the current scope and its children.
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* Because a {@link ng.$rootScope.Scope#$watch watcher}'s listener can change the model, the
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* `$digest()` keeps calling the {@link ng.$rootScope.Scope#$watch watchers} until no more listeners are
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* firing. This means that it is possible to get into an infinite loop. This function will throw
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* `'Maximum iteration limit exceeded.'` if the number of iterations exceeds 10.
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*
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* Usually you don't call `$digest()` directly in
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* {@link ng.directive:ngController controllers} or in
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* {@link ng.$compileProvider.directive directives}.
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* Instead a call to {@link ng.$rootScope.Scope#$apply $apply()} (typically from within a
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* {@link ng.$compileProvider.directive directives}) will force a `$digest()`.
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*
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* If you want to be notified whenever `$digest()` is called,
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* you can register a `watchExpression` function with {@link ng.$rootScope.Scope#$watch $watch()}
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* with no `listener`.
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*
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* You may have a need to call `$digest()` from within unit-tests, to simulate the scope
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* life-cycle.
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*
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* # Example
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* <pre>
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var scope = ...;
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scope.name = 'misko';
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scope.counter = 0;
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expect(scope.counter).toEqual(0);
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scope.$watch('name', function(newValue, oldValue) {
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counter = counter + 1;
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});
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expect(scope.counter).toEqual(0);
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scope.$digest();
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// no variable change
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expect(scope.counter).toEqual(0);
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scope.name = 'adam';
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scope.$digest();
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expect(scope.counter).toEqual(1);
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* </pre>
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*
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*/
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$digest: function() {
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var watch, value, last,
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watchers,
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asyncQueue,
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length,
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dirty, ttl = TTL,
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next, current, target = this,
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watchLog = [],
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logIdx, logMsg;
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beginPhase('$digest');
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do {
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dirty = false;
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current = target;
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do {
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asyncQueue = current.$$asyncQueue;
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while(asyncQueue.length) {
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try {
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current.$eval(asyncQueue.shift());
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} catch (e) {
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$exceptionHandler(e);
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}
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}
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if ((watchers = current.$$watchers)) {
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// process our watches
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length = watchers.length;
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while (length--) {
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try {
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watch = watchers[length];
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// Most common watches are on primitives, in which case we can short
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// circuit it with === operator, only when === fails do we use .equals
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if ((value = watch.get(current)) !== (last = watch.last) &&
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!(watch.eq
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? equals(value, last)
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: (typeof value == 'number' && typeof last == 'number'
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&& isNaN(value) && isNaN(last)))) {
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dirty = true;
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watch.last = watch.eq ? copy(value) : value;
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watch.fn(value, ((last === initWatchVal) ? value : last), current);
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if (ttl < 5) {
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logIdx = 4 - ttl;
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if (!watchLog[logIdx]) watchLog[logIdx] = [];
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logMsg = (isFunction(watch.exp))
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? 'fn: ' + (watch.exp.name || watch.exp.toString())
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: watch.exp;
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logMsg += '; newVal: ' + toJson(value) + '; oldVal: ' + toJson(last);
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watchLog[logIdx].push(logMsg);
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}
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}
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} catch (e) {
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$exceptionHandler(e);
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}
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}
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}
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// Insanity Warning: scope depth-first traversal
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// yes, this code is a bit crazy, but it works and we have tests to prove it!
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// this piece should be kept in sync with the traversal in $broadcast
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if (!(next = (current.$$childHead || (current !== target && current.$$nextSibling)))) {
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while(current !== target && !(next = current.$$nextSibling)) {
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current = current.$parent;
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}
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}
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} while ((current = next));
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if(dirty && !(ttl--)) {
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clearPhase();
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throw Error(TTL + ' $digest() iterations reached. Aborting!\n' +
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'Watchers fired in the last 5 iterations: ' + toJson(watchLog));
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}
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} while (dirty || asyncQueue.length);
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clearPhase();
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},
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/**
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* @ngdoc event
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* @name ng.$rootScope.Scope#$destroy
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* @eventOf ng.$rootScope.Scope
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* @eventType broadcast on scope being destroyed
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*
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* @description
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* Broadcasted when a scope and its children are being destroyed.
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*/
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/**
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* @ngdoc function
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* @name ng.$rootScope.Scope#$destroy
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* @methodOf ng.$rootScope.Scope
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* @function
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*
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* @description
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* Remove the current scope (and all of its children) from the parent scope. Removal implies
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* that calls to {@link ng.$rootScope.Scope#$digest $digest()} will no longer
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* propagate to the current scope and its children. Removal also implies that the current
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* scope is eligible for garbage collection.
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*
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* The `$destroy()` is usually used by directives such as
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* {@link ng.directive:ngRepeat ngRepeat} for managing the
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* unrolling of the loop.
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*
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* Just before a scope is destroyed a `$destroy` event is broadcasted on this scope.
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* Application code can register a `$destroy` event handler that will give it chance to
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* perform any necessary cleanup.
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*/
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$destroy: function() {
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if ($rootScope == this) return; // we can't remove the root node;
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var parent = this.$parent;
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this.$broadcast('$destroy');
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if (parent.$$childHead == this) parent.$$childHead = this.$$nextSibling;
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if (parent.$$childTail == this) parent.$$childTail = this.$$prevSibling;
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if (this.$$prevSibling) this.$$prevSibling.$$nextSibling = this.$$nextSibling;
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if (this.$$nextSibling) this.$$nextSibling.$$prevSibling = this.$$prevSibling;
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},
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/**
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* @ngdoc function
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* @name ng.$rootScope.Scope#$eval
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* @methodOf ng.$rootScope.Scope
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* @function
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*
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* @description
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* Executes the `expression` on the current scope returning the result. Any exceptions in the
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* expression are propagated (uncaught). This is useful when evaluating engular expressions.
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*
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* # Example
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* <pre>
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var scope = ng.$rootScope.Scope();
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scope.a = 1;
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scope.b = 2;
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expect(scope.$eval('a+b')).toEqual(3);
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expect(scope.$eval(function(scope){ return scope.a + scope.b; })).toEqual(3);
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* </pre>
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*
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* @param {(string|function())=} expression An angular expression to be executed.
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*
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|
* - `string`: execute using the rules as defined in {@link guide/expression expression}.
|
|
* - `function(scope)`: execute the function with the current `scope` parameter.
|
|
*
|
|
* @returns {*} The result of evaluating the expression.
|
|
*/
|
|
$eval: function(expr, locals) {
|
|
return $parse(expr)(this, locals);
|
|
},
|
|
|
|
/**
|
|
* @ngdoc function
|
|
* @name ng.$rootScope.Scope#$evalAsync
|
|
* @methodOf ng.$rootScope.Scope
|
|
* @function
|
|
*
|
|
* @description
|
|
* Executes the expression on the current scope at a later point in time.
|
|
*
|
|
* The `$evalAsync` makes no guarantees as to when the `expression` will be executed, only that:
|
|
*
|
|
* - it will execute in the current script execution context (before any DOM rendering).
|
|
* - at least one {@link ng.$rootScope.Scope#$digest $digest cycle} will be performed after
|
|
* `expression` execution.
|
|
*
|
|
* Any exceptions from the execution of the expression are forwarded to the
|
|
* {@link ng.$exceptionHandler $exceptionHandler} service.
|
|
*
|
|
* @param {(string|function())=} expression An angular expression to be executed.
|
|
*
|
|
* - `string`: execute using the rules as defined in {@link guide/expression expression}.
|
|
* - `function(scope)`: execute the function with the current `scope` parameter.
|
|
*
|
|
*/
|
|
$evalAsync: function(expr) {
|
|
this.$$asyncQueue.push(expr);
|
|
},
|
|
|
|
/**
|
|
* @ngdoc function
|
|
* @name ng.$rootScope.Scope#$apply
|
|
* @methodOf ng.$rootScope.Scope
|
|
* @function
|
|
*
|
|
* @description
|
|
* `$apply()` is used to execute an expression in angular from outside of the angular framework.
|
|
* (For example from browser DOM events, setTimeout, XHR or third party libraries).
|
|
* Because we are calling into the angular framework we need to perform proper scope life-cycle
|
|
* of {@link ng.$exceptionHandler exception handling},
|
|
* {@link ng.$rootScope.Scope#$digest executing watches}.
|
|
*
|
|
* ## Life cycle
|
|
*
|
|
* # Pseudo-Code of `$apply()`
|
|
* <pre>
|
|
function $apply(expr) {
|
|
try {
|
|
return $eval(expr);
|
|
} catch (e) {
|
|
$exceptionHandler(e);
|
|
} finally {
|
|
$root.$digest();
|
|
}
|
|
}
|
|
* </pre>
|
|
*
|
|
*
|
|
* Scope's `$apply()` method transitions through the following stages:
|
|
*
|
|
* 1. The {@link guide/expression expression} is executed using the
|
|
* {@link ng.$rootScope.Scope#$eval $eval()} method.
|
|
* 2. Any exceptions from the execution of the expression are forwarded to the
|
|
* {@link ng.$exceptionHandler $exceptionHandler} service.
|
|
* 3. The {@link ng.$rootScope.Scope#$watch watch} listeners are fired immediately after the expression
|
|
* was executed using the {@link ng.$rootScope.Scope#$digest $digest()} method.
|
|
*
|
|
*
|
|
* @param {(string|function())=} exp An angular expression to be executed.
|
|
*
|
|
* - `string`: execute using the rules as defined in {@link guide/expression expression}.
|
|
* - `function(scope)`: execute the function with current `scope` parameter.
|
|
*
|
|
* @returns {*} The result of evaluating the expression.
|
|
*/
|
|
$apply: function(expr) {
|
|
try {
|
|
beginPhase('$apply');
|
|
return this.$eval(expr);
|
|
} catch (e) {
|
|
$exceptionHandler(e);
|
|
} finally {
|
|
clearPhase();
|
|
try {
|
|
$rootScope.$digest();
|
|
} catch (e) {
|
|
$exceptionHandler(e);
|
|
throw e;
|
|
}
|
|
}
|
|
},
|
|
|
|
/**
|
|
* @ngdoc function
|
|
* @name ng.$rootScope.Scope#$on
|
|
* @methodOf ng.$rootScope.Scope
|
|
* @function
|
|
*
|
|
* @description
|
|
* Listen on events of a given type. See {@link ng.$rootScope.Scope#$emit $emit} for discussion of
|
|
* event life cycle.
|
|
*
|
|
* @param {string} name Event name to listen on.
|
|
* @param {function(event)} listener Function to call when the event is emitted.
|
|
* @returns {function()} Returns a deregistration function for this listener.
|
|
*
|
|
* The event listener function format is: `function(event, args...)`. The `event` object
|
|
* passed into the listener has the following attributes:
|
|
*
|
|
* - `targetScope` - {Scope}: the scope on which the event was `$emit`-ed or `$broadcast`-ed.
|
|
* - `currentScope` - {Scope}: the current scope which is handling the event.
|
|
* - `name` - {string}: Name of the event.
|
|
* - `stopPropagation` - {function=}: calling `stopPropagation` function will cancel further event propagation
|
|
* (available only for events that were `$emit`-ed).
|
|
* - `preventDefault` - {function}: calling `preventDefault` sets `defaultPrevented` flag to true.
|
|
* - `defaultPrevented` - {boolean}: true if `preventDefault` was called.
|
|
*/
|
|
$on: function(name, listener) {
|
|
var namedListeners = this.$$listeners[name];
|
|
if (!namedListeners) {
|
|
this.$$listeners[name] = namedListeners = [];
|
|
}
|
|
namedListeners.push(listener);
|
|
|
|
return function() {
|
|
arrayRemove(namedListeners, listener);
|
|
};
|
|
},
|
|
|
|
|
|
/**
|
|
* @ngdoc function
|
|
* @name ng.$rootScope.Scope#$emit
|
|
* @methodOf ng.$rootScope.Scope
|
|
* @function
|
|
*
|
|
* @description
|
|
* Dispatches an event `name` upwards through the scope hierarchy notifying the
|
|
* registered {@link ng.$rootScope.Scope#$on} listeners.
|
|
*
|
|
* The event life cycle starts at the scope on which `$emit` was called. All
|
|
* {@link ng.$rootScope.Scope#$on listeners} listening for `name` event on this scope get notified.
|
|
* Afterwards, the event traverses upwards toward the root scope and calls all registered
|
|
* listeners along the way. The event will stop propagating if one of the listeners cancels it.
|
|
*
|
|
* Any exception emmited from the {@link ng.$rootScope.Scope#$on listeners} will be passed
|
|
* onto the {@link ng.$exceptionHandler $exceptionHandler} service.
|
|
*
|
|
* @param {string} name Event name to emit.
|
|
* @param {...*} args Optional set of arguments which will be passed onto the event listeners.
|
|
* @return {Object} Event object, see {@link ng.$rootScope.Scope#$on}
|
|
*/
|
|
$emit: function(name, args) {
|
|
var empty = [],
|
|
namedListeners,
|
|
scope = this,
|
|
stopPropagation = false,
|
|
event = {
|
|
name: name,
|
|
targetScope: scope,
|
|
stopPropagation: function() {stopPropagation = true;},
|
|
preventDefault: function() {
|
|
event.defaultPrevented = true;
|
|
},
|
|
defaultPrevented: false
|
|
},
|
|
listenerArgs = concat([event], arguments, 1),
|
|
i, length;
|
|
|
|
do {
|
|
namedListeners = scope.$$listeners[name] || empty;
|
|
event.currentScope = scope;
|
|
for (i=0, length=namedListeners.length; i<length; i++) {
|
|
try {
|
|
namedListeners[i].apply(null, listenerArgs);
|
|
if (stopPropagation) return event;
|
|
} catch (e) {
|
|
$exceptionHandler(e);
|
|
}
|
|
}
|
|
//traverse upwards
|
|
scope = scope.$parent;
|
|
} while (scope);
|
|
|
|
return event;
|
|
},
|
|
|
|
|
|
/**
|
|
* @ngdoc function
|
|
* @name ng.$rootScope.Scope#$broadcast
|
|
* @methodOf ng.$rootScope.Scope
|
|
* @function
|
|
*
|
|
* @description
|
|
* Dispatches an event `name` downwards to all child scopes (and their children) notifying the
|
|
* registered {@link ng.$rootScope.Scope#$on} listeners.
|
|
*
|
|
* The event life cycle starts at the scope on which `$broadcast` was called. All
|
|
* {@link ng.$rootScope.Scope#$on listeners} listening for `name` event on this scope get notified.
|
|
* Afterwards, the event propagates to all direct and indirect scopes of the current scope and
|
|
* calls all registered listeners along the way. The event cannot be canceled.
|
|
*
|
|
* Any exception emmited from the {@link ng.$rootScope.Scope#$on listeners} will be passed
|
|
* onto the {@link ng.$exceptionHandler $exceptionHandler} service.
|
|
*
|
|
* @param {string} name Event name to emit.
|
|
* @param {...*} args Optional set of arguments which will be passed onto the event listeners.
|
|
* @return {Object} Event object, see {@link ng.$rootScope.Scope#$on}
|
|
*/
|
|
$broadcast: function(name, args) {
|
|
var target = this,
|
|
current = target,
|
|
next = target,
|
|
event = {
|
|
name: name,
|
|
targetScope: target,
|
|
preventDefault: function() {
|
|
event.defaultPrevented = true;
|
|
},
|
|
defaultPrevented: false
|
|
},
|
|
listenerArgs = concat([event], arguments, 1);
|
|
|
|
//down while you can, then up and next sibling or up and next sibling until back at root
|
|
do {
|
|
current = next;
|
|
event.currentScope = current;
|
|
forEach(current.$$listeners[name], function(listener) {
|
|
try {
|
|
listener.apply(null, listenerArgs);
|
|
} catch(e) {
|
|
$exceptionHandler(e);
|
|
}
|
|
});
|
|
|
|
// Insanity Warning: scope depth-first traversal
|
|
// yes, this code is a bit crazy, but it works and we have tests to prove it!
|
|
// this piece should be kept in sync with the traversal in $digest
|
|
if (!(next = (current.$$childHead || (current !== target && current.$$nextSibling)))) {
|
|
while(current !== target && !(next = current.$$nextSibling)) {
|
|
current = current.$parent;
|
|
}
|
|
}
|
|
} while ((current = next));
|
|
|
|
return event;
|
|
}
|
|
};
|
|
|
|
var $rootScope = new Scope();
|
|
|
|
return $rootScope;
|
|
|
|
|
|
function beginPhase(phase) {
|
|
if ($rootScope.$$phase) {
|
|
throw Error($rootScope.$$phase + ' already in progress');
|
|
}
|
|
|
|
$rootScope.$$phase = phase;
|
|
}
|
|
|
|
function clearPhase() {
|
|
$rootScope.$$phase = null;
|
|
}
|
|
|
|
function compileToFn(exp, name) {
|
|
var fn = $parse(exp);
|
|
assertArgFn(fn, name);
|
|
return fn;
|
|
}
|
|
|
|
/**
|
|
* function used as an initial value for watchers.
|
|
* because it's uniqueue we can easily tell it apart from other values
|
|
*/
|
|
function initWatchVal() {}
|
|
}];
|
|
}
|