Xamarin.Forms
Generic Xamarin.Forms app-livscykel? Plattform beroende!

Xamarin.Forms livscykel är inte den faktiska appens livscykel utan en plattformsrepresentation av den.

Låt oss titta på de ursprungliga appens livscykelmetoder för olika plattformar.

Android.

//Xamarin.Forms.Platform.Android.FormsApplicationActivity lifecycle methods:
protected override void OnCreate(Bundle savedInstanceState);
protected override void OnDestroy();
protected override void OnPause();
protected override void OnRestart();
protected override void OnResume();
protected override void OnStart();
protected override void OnStop();

iOS.

//Xamarin.Forms.Platform.iOS.FormsApplicationDelegate lifecycle methods:
public override void DidEnterBackground(UIApplication uiApplication);
public override bool FinishedLaunching(UIApplication uiApplication, NSDictionary launchOptions);
public override void OnActivated(UIApplication uiApplication);
public override void OnResignActivation(UIApplication uiApplication);
public override void WillEnterForeground(UIApplication uiApplication);
public override bool WillFinishLaunching(UIApplication uiApplication, NSDictionary launchOptions);
public override void WillTerminate(UIApplication uiApplication);

Windows.

//Windows.UI.Xaml.Application lifecycle methods:
public event EventHandler<System.Object> Resuming;
public event SuspendingEventHandler Suspending;    
protected virtual void OnActivated(IActivatedEventArgs args);
protected virtual void OnFileActivated(FileActivatedEventArgs args);
protected virtual void OnFileOpenPickerActivated(FileOpenPickerActivatedEventArgs args);
protected virtual void OnFileSavePickerActivated(FileSavePickerActivatedEventArgs args);
protected virtual void OnLaunched(LaunchActivatedEventArgs args);
protected virtual void OnSearchActivated(SearchActivatedEventArgs args);
protected virtual void OnShareTargetActivated(ShareTargetActivatedEventArgs args);
protected virtual void OnWindowCreated(WindowCreatedEventArgs args);

//Windows.UI.Xaml.Window lifecycle methods:
public event WindowActivatedEventHandler Activated;
public event WindowClosedEventHandler Closed;
public event WindowVisibilityChangedEventHandler VisibilityChanged;

Och nu Xamarin.Forms app-livscykelmetoder:

//Xamarin.Forms.Application lifecycle methods:
protected virtual void OnResume();
protected virtual void OnSleep();
protected virtual void OnStart();

Vad du enkelt kan berätta genom att bara följa listorna, Xamarin.Forms-plattformens appcykelns livscykelperspektiv är mycket förenklad. Det ger dig generisk ledtråd om vilket tillstånd din app är i men i de flesta produktionsfall måste du bygga en plattformsberoende logik.