AppLifecycleListener class
A listener that can be used to listen to changes in the application lifecycle.
To listen for requests for the application to exit, and to decide whether or not the application should exit when requested, create an AppLifecycleListener and set the onExitRequested callback.
To listen for changes in the application lifecycle state, define an onStateChange callback. See the AppLifecycleState enum for details on the various states.
The onStateChange callback is called for each state change, and the individual state transitions (onResume, onInactive, etc.) are also called if the state transition they represent occurs.
State changes will occur in accordance with the state machine described by this diagram:
The initial state of the state machine is the AppLifecycleState.detached state, and the arrows describe valid state transitions. Transitions in blue are transitions that only happen on iOS and Android.
This example shows how an application can listen to changes in the
application state.
link
To create a local project with this code sample, run:
flutter create --sample=widgets.AppLifecycleListener.1 mysample
This example shows how an application can optionally decide to abort a
request for exiting instead of obeying the request.
link
To create a local project with this code sample, run:
flutter create --sample=widgets.AppLifecycleListener.2 mysample
See also:
- ServicesBinding.exitApplication for a function to call that will request that the application exits.
- WidgetsBindingObserver.didRequestAppExit for the handler which this class uses to receive exit requests.
- WidgetsBindingObserver.didChangeAppLifecycleState for the handler which this class uses to receive lifecycle state changes.
- Mixed in types
Constructors
-
AppLifecycleListener({WidgetsBinding? binding, VoidCallback? onResume, VoidCallback? onInactive, VoidCallback? onHide, VoidCallback? onShow, VoidCallback? onPause, VoidCallback? onRestart, VoidCallback? onDetach, AppExitRequestCallback? onExitRequested, ValueChanged<
AppLifecycleState> ? onStateChange}) - Creates an AppLifecycleListener.
Properties
- binding → WidgetsBinding
-
The WidgetsBinding to listen to for application lifecycle events.
final
- hashCode → int
-
The hash code for this object.
no setterinherited
- onDetach → VoidCallback?
-
A callback that is called when an application has exited, and detached all
host views from the engine.
final
- onExitRequested → AppExitRequestCallback?
-
A callback used to ask the application if it will allow exiting the
application for cases where the exit is cancelable.
final
- onHide → VoidCallback?
-
A callback that is called when the application is hidden.
final
- onInactive → VoidCallback?
-
A callback that is called when the application loses input focus.
final
- onPause → VoidCallback?
-
A callback that is called when the application is paused.
final
- onRestart → VoidCallback?
-
A callback that is called when the application is resumed after being
paused.
final
- onResume → VoidCallback?
-
A callback that is called when a view in the application gains input
focus.
final
- onShow → VoidCallback?
-
A callback that is called when the application is shown.
final
-
onStateChange
→ ValueChanged<
AppLifecycleState> ? -
Called anytime the state changes, passing the new state.
final
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
Methods
-
debugFillProperties(
DiagnosticPropertiesBuilder properties) → void -
Add additional properties associated with the node.
override
-
didChangeAccessibilityFeatures(
) → void -
Called when the system changes the set of currently active accessibility
features.
inherited
-
didChangeAppLifecycleState(
AppLifecycleState state) → void -
Called when the system puts the app in the background or returns
the app to the foreground.
override
-
didChangeLocales(
List< Locale> ? locales) → void -
Called when the system tells the app that the user's locale has
changed. For example, if the user changes the system language
settings.
inherited
-
didChangeMetrics(
) → void -
Called when the application's dimensions change. For example,
when a phone is rotated.
inherited
-
didChangePlatformBrightness(
) → void -
Called when the platform brightness changes.
inherited
-
didChangeTextScaleFactor(
) → void -
Called when the platform's text scale factor changes.
inherited
-
didChangeViewFocus(
ViewFocusEvent event) → void -
Called whenever the PlatformDispatcher receives a notification that the
focus state on a view has changed.
inherited
-
didHaveMemoryPressure(
) → void -
Called when the system is running low on memory.
inherited
-
didPopRoute(
) → Future< bool> -
Called when the system tells the app to pop the current route, such as
after a system back button press or back gesture.
inherited
-
didPushRoute(
String route) → Future< bool> -
Called when the host tells the application to push a new route onto the
navigator.
inherited
-
didPushRouteInformation(
RouteInformation routeInformation) → Future< bool> -
Called when the host tells the application to push a new
RouteInformation and a restoration state onto the router.
inherited
-
didRequestAppExit(
) → Future< AppExitResponse> -
Called when a request is received from the system to exit the application.
override
-
dispose(
) → void - Call when the listener is no longer in use.
-
handleCancelBackGesture(
) → void -
Called when a predictive back gesture is canceled, indicating that no
navigation should occur.
inherited
-
handleCommitBackGesture(
) → void -
Called when a predictive back gesture is finished successfully, indicating
that the current route should be popped.
inherited
-
handleStartBackGesture(
PredictiveBackEvent backEvent) → bool -
Called at the start of a predictive back gesture.
inherited
-
handleUpdateBackGestureProgress(
PredictiveBackEvent backEvent) → void -
Called when a predictive back gesture moves.
inherited
-
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a nonexistent method or property is accessed.
inherited
-
toDiagnosticsNode(
{String? name, DiagnosticsTreeStyle? style}) → DiagnosticsNode -
Returns a debug representation of the object that is used by debugging
tools and by DiagnosticsNode.toStringDeep.
inherited
-
toString(
{DiagnosticLevel minLevel = DiagnosticLevel.info}) → String -
A string representation of this object.
inherited
-
toStringShort(
) → String -
A brief description of this object, usually just the runtimeType and the
hashCode.
inherited
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited