p.
  <span class="location-badge">exported from <a href="/angular2/change_detection">angular2/change_detection</a></span>
  defined in <a href="https://github.com/angular/angular/tree/master/modules/angular2/src/core/life_cycle/life_cycle.js#L31">angular2/src/core/life_cycle/life_cycle.js (line 31)</a>

:markdown
  Provides access to explicitly trigger change detection in an application.
  
  By default, `Zone` triggers change detection in Angular on each virtual machine (VM) turn. When testing, or in some
  limited application use cases, a developer can also trigger change detection with the `lifecycle.tick()` method.
  
  Each Angular application has a single `LifeCycle` instance.
  
  # Example
  
  This is a contrived example, since the bootstrap automatically runs inside of the `Zone`, which invokes
  `lifecycle.tick()` on your behalf.
  
  ```javascript
  bootstrap(MyApp).then((ref:ComponentRef) => {
    var lifeCycle = ref.injector.get(LifeCycle);
    var myApp = ref.instance;
  
    ref.doSomething();
    lifecycle.tick();
  });
  ```
.l-main-section
  h2 Members
  .l-sub-section
    h3 constructor

    
    pre.prettyprint
      code.
        constructor(exceptionHandler:ExceptionHandler, changeDetector:ChangeDetector = null, enforceNoNewChanges:boolean = false)
    

    :markdown
      




  .l-sub-section
    h3 registerWith

    
    pre.prettyprint
      code.
        registerWith(zone:VmTurnZone, changeDetector:ChangeDetector = null)
    

    :markdown
      





  .l-sub-section
    h3 tick

    
    pre.prettyprint
      code.
        tick()
    

    :markdown
      Invoke this method to explicitly process change detection and its side-effects.
      
       In development mode, `tick()` also performs a second change detection cycle to ensure that no further
       changes are detected. If additional changes are picked up during this second cycle, bindings in the app have
       side-effects that cannot be resolved in a single change detection pass. In this case, Angular throws an error,
       since an Angular application can only have one change detection pass during which all change detection must
       complete.