diff options
Diffstat (limited to 'docs/content/guide/scope.ngdoc')
| -rw-r--r-- | docs/content/guide/scope.ngdoc | 66 |
1 files changed, 33 insertions, 33 deletions
diff --git a/docs/content/guide/scope.ngdoc b/docs/content/guide/scope.ngdoc index dac69d8a..ac0089c9 100644 --- a/docs/content/guide/scope.ngdoc +++ b/docs/content/guide/scope.ngdoc @@ -4,32 +4,32 @@ # What are Scopes? -{@link api/angular.module.ng.$rootScope.Scope scope} is an object that refers to the application +{@link api/ng.$rootScope.Scope scope} is an object that refers to the application model. It is an execution context for {@link expression expressions}. Scopes are arranged in hierarchical structure which mimic the DOM structure of the application. Scopes can watch {@link guide/expression expressions} and propagate events. ## Scope characteristics - - Scopes provide APIs ({@link api/angular.module.ng.$rootScope.Scope#$watch $watch}) to observe + - Scopes provide APIs ({@link api/ng.$rootScope.Scope#$watch $watch}) to observe model mutations. - - Scopes provide APIs ({@link api/angular.module.ng.$rootScope.Scope#$apply $apply}) to + - Scopes provide APIs ({@link api/ng.$rootScope.Scope#$apply $apply}) to propagate any model changes through the system into the view from outside of the "Angular realm" (controllers, services, Angular event handlers). - Scopes can be nested to isolate application components while providing access to shared model properties. A scope (prototypically) inherits properties from its parent scope. - - Scopes provide context against which {@link guide/expression expressions} are evaluated. For + - Scopes provide context against which {@link guide/expression expressions} are evaluated. For example `{{username}}` expression is meaningless, unless it is evaluated against a specific scope which defines the `username` property. ## Scope as Data-Model Scope is the glue between application controller and the view. During the template {@link compiler -linking} phase the {@link api/angular.module.ng.$compileProvider.directive directives} set up -{@link api/angular.module.ng.$rootScope.Scope#$watch `$watch`} expressions on the scope. The +linking} phase the {@link api/ng.$compileProvider.directive directives} set up +{@link api/ng.$rootScope.Scope#$watch `$watch`} expressions on the scope. The `$watch` allows the directives to be notified of property changes, which allows the directive to render the updated value to the DOM. @@ -102,7 +102,7 @@ to test the behavior without being distracted by the rendering details. ## Scope Hierarchies -Each Angular application has exactly one {@link api/angular.module.ng.$rootScope root scope}, but +Each Angular application has exactly one {@link api/ng.$rootScope root scope}, but may have several child scopes. The application can have multiple scopes, because some {@link guide/directive directives} create @@ -164,7 +164,7 @@ where the `department` property is defined. Scopes are attached to the DOM as `$scope` data property, and can be retrieved for debugging purposes. (It is unlikely that one would need to retrieve scopes in this way inside the application.) The location where the root scope is attached to the DOM is defined by the location -of {@link api/angular.module.ng.$compileProvider.directive.ngApp `ng-app`} directive. Typically +of {@link api/ng.directive:ngApp `ng-app`} directive. Typically `ng-app` is placed an the `<html>` element, but it can be placed on other elements as well, if, for example, only a portion of the view needs to be controlled by angular. @@ -182,8 +182,8 @@ To examine the scope in the debugger: ## Scope Events Propagation Scopes can propagate events in similar fashion to DOM events. The event can be {@link -api/angular.module.ng.$rootScope.Scope#$broadcast broadcasted} to the scope children or {@link -api/angular.module.ng.$rootScope.Scope#$emit emitted} to scope parents. +api/ng.$rootScope.Scope#$broadcast broadcasted} to the scope children or {@link +api/ng.$rootScope.Scope#$emit emitted} to scope parents. <example> <file name="script.js"> @@ -225,14 +225,14 @@ more events. When the browser calls into JavaScript the code executes outside they Angular execution context, which means that Angular is unaware of model modifications. To properly process model modifications the execution has to enter the Angular execution context using the {@link -api/angular.module.ng.$rootScope.Scope#$apply `$apply`} method. Only model modifications which +api/ng.$rootScope.Scope#$apply `$apply`} method. Only model modifications which execute inside the `$apply` method will be properly accounted for by Angular. For example if a directive listens on DOM events, such as {@link -api/angular.module.ng.$compileProvider.directive.ngClick `ng-click`} it must evaluate the +api/ng.directive:ngClick `ng-click`} it must evaluate the expression inside the `$apply` method. After evaluating the expression `$apply` method performs a {@link -api/angular.module.ng.$rootScope.Scope#$digest `$digest`}. In $digest phase the scope examines all +api/ng.$rootScope.Scope#$digest `$digest`}. In $digest phase the scope examines all of the `$watch` expressions and compares them with previous value. This dirty checking, is done asynchronously. This means that assignment such as `$scope.username="angular"` will not immediately cause a `$watch` to be notified, instead the `$watch` notification is delayed until @@ -243,27 +243,27 @@ the `$digest` phase. This delay is desirable, since it coalesces multiple model 1. **Creation** - The {@link api/angular.module.ng.$rootScope root scope} is created during the application - bootstrap by the {@link api/angular.module.AUTO.$injector $injector}. During template + The {@link api/ng.$rootScope root scope} is created during the application + bootstrap by the {@link api/AUTO.$injector $injector}. During template linking, some directives create new child scopes. 2. **Watcher registration** During template linking directives register {@link - api/angular.module.ng.$rootScope.Scope#$watch watches} on the scope. This watches will be + api/ng.$rootScope.Scope#$watch watches} on the scope. This watches will be used to propagate model values to the DOM. 3. **Model mutation** For mutations to be properly observed, you should make them only within the {@link - api/angular.module.ng.$rootScope.Scope#$apply scope.$apply()}. (Angular apis do this + api/ng.$rootScope.Scope#$apply scope.$apply()}. (Angular apis do this implicitly, so no extra `$apply` call is needed when doing synchronous work in controllers, - or asynchronous work with {@link api/angular.module.ng.$http $http} or {@link - api/angular.module.ng.$defer $defer} services. + or asynchronous work with {@link api/ng.$http $http} or {@link + api/ng.$defer $defer} services. 4. **Mutation observation** - At the end `$apply`, Angular performs a {@link api/angular.module.ng.$rootScope.Scope#$digest + At the end `$apply`, Angular performs a {@link api/ng.$rootScope.Scope#$digest $digest} cycle on the root scope, which then propagates throughout all child scopes. During the `$digest` cycle, all `$watch`ed expressions or functions are checked for model mutation and if a mutation is detected, the `$watch` listener is called. @@ -271,7 +271,7 @@ the `$digest` phase. This delay is desirable, since it coalesces multiple model 5. **Scope destruction** When child scopes are no longer needed, it is the responsibility of the child scope creator - to destroy them via {@link api/angular.module.ng.$rootScope.Scope#$destroy scope.$destroy()} + to destroy them via {@link api/ng.$rootScope.Scope#$destroy scope.$destroy()} API. This will stop propagation of `$digest` calls into the child scope and allow for memory used by the child scope models to be reclaimed by the garbage collector. @@ -279,30 +279,30 @@ the `$digest` phase. This delay is desirable, since it coalesces multiple model ### Scopes and Directives During the compilation phase, the {@link compiler compiler} matches {@link -api/angular.module.ng.$compileProvider.directive directives} against the DOM template. The directives +api/ng.$compileProvider.directive directives} against the DOM template. The directives usually fall into one of two categories: - - Observing {@link api/angular.module.ng.$compileProvider.directive directives}, such as + - Observing {@link api/ng.$compileProvider.directive directives}, such as double-curly expressions `{{expression}}`, register listeners using the {@link - api/angular.module.ng.$rootScope.Scope#$watch $watch()} method. This type of directive needs + api/ng.$rootScope.Scope#$watch $watch()} method. This type of directive needs to be notified whenever the expression changes so that it can update the view. - - Listener directives, such as {@link api/angular.module.ng.$compileProvider.directive.ngClick + - Listener directives, such as {@link api/ng.directive:ngClick ng-click}, register a listener with the DOM. When the DOM listener fires, the directive executes the associated expression and updates the view using the {@link - api/angular.module.ng.$rootScope.Scope#$apply $apply()} method. + api/ng.$rootScope.Scope#$apply $apply()} method. When an external event (such as a user action, timer or XHR) is received, the associated {@link expression expression} must be applied to the scope through the {@link -api/angular.module.ng.$rootScope.Scope#$apply $apply()} method so that all listeners are updated +api/ng.$rootScope.Scope#$apply $apply()} method so that all listeners are updated correctly. ### Directives that Create Scopes -In most cases, {@link api/angular.module.ng.$compileProvider.directive directives} and scopes interact +In most cases, {@link api/ng.$compileProvider.directive directives} and scopes interact but do not create new instances of scope. However, some directives, such as {@link -api/angular.module.ng.$compileProvider.directive.ngController ng-controller} and {@link -api/angular.module.ng.$compileProvider.directive.ngRepeat ng-repeat}, create new child scopes +api/ng.directive:ngController ng-controller} and {@link +api/ng.directive:ngRepeat ng-repeat}, create new child scopes and attach the child scope to the corresponding DOM element. You can retrieve a scope for any DOM element by using an `angular.element(aDomElement).scope()` method call. @@ -311,14 +311,14 @@ element by using an `angular.element(aDomElement).scope()` method call. Scopes and controllers interact with each other in the following situations: - Controllers use scopes to expose controller methods to templates (see {@link - api/angular.module.ng.$compileProvider.directive.ngController ng-controller}). + api/ng.directive:ngController ng-controller}). - Controllers define methods (behavior) that can mutate the model (properties on the scope). - - Controllers may register {@link api/angular.module.ng.$rootScope.Scope#$watch watches} on + - Controllers may register {@link api/ng.$rootScope.Scope#$watch watches} on the model. These watches execute immediately after the controller behavior executes. -See the {@link api/angular.module.ng.$compileProvider.directive.ngController ng-controller} for more +See the {@link api/ng.directive:ngController ng-controller} for more information. |