SchedulerBinding mixin Null safety
Scheduler for running the following:
-
Transient callbacks, triggered by the system's dart:ui.PlatformDispatcher.onBeginFrame callback, for synchronizing the application's behavior to the system's display. For example, Tickers and AnimationControllers trigger from these.
-
Persistent callbacks, triggered by the system's dart:ui.PlatformDispatcher.onDrawFrame callback, for updating the system's display after transient callbacks have executed. For example, the rendering layer uses this to drive its rendering pipeline.
-
Post-frame callbacks, which are run after persistent callbacks, just before returning from the dart:ui.PlatformDispatcher.onDrawFrame callback.
-
Non-rendering tasks, to be run between frames. These are given a priority and are executed in priority order according to a schedulingStrategy.
- Superclass Constraints
- Mixin Applications
Properties
- schedulingStrategy ↔ SchedulingStrategy
-
The strategy to use when deciding whether to run a task or not.
read / write
- lifecycleState → AppLifecycleState?
-
Whether the application is visible, and if so, whether it is currently
interactive.
read-only
- transientCallbackCount → int
-
The current number of transient frame callbacks scheduled.
read-only
-
endOfFrame
→ Future<
void> -
Returns a Future that completes after the frame completes.
read-only
- hasScheduledFrame → bool
-
Whether this scheduler has requested that handleBeginFrame be called soon.
read-only
- schedulerPhase → SchedulerPhase
-
The phase that the scheduler is currently operating under.
read-only
- framesEnabled → bool
-
Whether frames are currently being scheduled when scheduleFrame is called.
read-only
- currentFrameTimeStamp → Duration
-
The time stamp for the frame currently being processed.
read-only
- currentSystemFrameTimeStamp → Duration
-
The raw time stamp as provided by the engine to
dart:ui.PlatformDispatcher.onBeginFrame for the frame currently being
processed.
read-only
- window → SingletonFlutterWindow
-
The main window to which this binding is bound.
read-onlyinherited
- platformDispatcher → PlatformDispatcher
-
The ui.PlatformDispatcher to which this binding is bound.
read-onlyinherited
- locked → bool
- Whether lockEvents is currently locking events.
- hashCode → int
-
The hash code for this object.
read-onlyinherited
- runtimeType → Type
-
A representation of the runtime type of the object.
read-onlyinherited
Methods
-
addPersistentFrameCallback(
FrameCallback callback) → void - Adds a persistent frame callback.
-
addPostFrameCallback(
FrameCallback callback) → void - Schedule a callback for the end of this frame.
-
addTimingsCallback(
TimingsCallback callback) → void - Add a TimingsCallback that receives FrameTiming sent from the engine.
-
cancelFrameCallbackWithId(
int id) → void -
Cancels the transient frame callback with the given
id. -
debugAssertNoTransientCallbacks(
String reason) → bool - Asserts that there are no registered transient callbacks; if there are, prints their locations and throws an exception.
-
ensureFrameCallbacksRegistered(
) → void -
Ensures callbacks for PlatformDispatcher.onBeginFrame and
PlatformDispatcher.onDrawFrame are registered.
protected">@protected
-
ensureVisualUpdate(
) → void - Schedules a new frame using scheduleFrame if this object is not currently producing a frame.
-
handleAppLifecycleStateChanged(
AppLifecycleState state) → void -
Called when the application lifecycle state changes.
mustCallSuper">@mustCallSuperprotected">@protected
-
handleBeginFrame(
Duration? rawTimeStamp) → void - Called by the engine to prepare the framework to produce a new frame.
-
handleDrawFrame(
) → void - Called by the engine to produce a new frame.
-
handleEventLoopCallback(
) → bool -
Execute the highest-priority task, if it is of a high enough priority.
visibleForTesting">@visibleForTesting
-
initInstances(
) → void -
The initialization method. Subclasses override this method to hook into
the platform and otherwise configure their services. Subclasses must call
"super.initInstances()".
override
-
initServiceExtensions(
) → void -
Called when the binding is initialized, to register service
extensions.
override
-
lockEvents(
Future< void> callback()) → Future<void> -
Locks the dispatching of asynchronous events and callbacks until the
callback's future completes.
protected">@protectedinherited
-
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a non-existent method or property is accessed.
inherited
-
performReassemble(
) → Future< void> - This method is called by reassembleApplication to actually cause the application to reassemble, e.g. after a hot reload.
-
postEvent(
String eventKind, Map< String, dynamic> eventData) → void -
All events dispatched by a BindingBase use this method instead of
calling developer.postEvent directly so that tests for BindingBase
can track which events were dispatched by overriding this method.
protected">@protectedinherited
-
reassembleApplication(
) → Future< void> -
Cause the entire application to redraw, e.g. after a hot reload.
inherited
-
registerBoolServiceExtension(
{required String name, required AsyncValueGetter< bool> getter, required AsyncValueSetter<bool> setter}) → void -
Registers a service extension method with the given name (full
name "ext.flutter.name"), which takes a single argument
"enabled" which can have the value "true" or the value "false"
or can be omitted to read the current value. (Any value other
than "true" is considered equivalent to "false". Other arguments
are ignored.)
protected">@protectedinherited
-
registerNumericServiceExtension(
{required String name, required AsyncValueGetter< double> getter, required AsyncValueSetter<double> setter}) → void -
Registers a service extension method with the given name (full
name "ext.flutter.name"), which takes a single argument with the
same name as the method which, if present, must have a value
that can be parsed by double.parse, and can be omitted to read
the current value. (Other arguments are ignored.)
protected">@protectedinherited
-
registerServiceExtension(
{required String name, required ServiceExtensionCallback callback}) → void -
Registers a service extension method with the given name (full name
"ext.flutter.name").
protected">@protectedinherited
-
registerSignalServiceExtension(
{required String name, required AsyncCallback callback}) → void -
Registers a service extension method with the given name (full
name "ext.flutter.name"), which takes no arguments and returns
no value.
protected">@protectedinherited
-
registerStringServiceExtension(
{required String name, required AsyncValueGetter< String> getter, required AsyncValueSetter<String> setter}) → void -
Registers a service extension method with the given name (full name
"ext.flutter.name"), which optionally takes a single argument with the
name "value". If the argument is omitted, the value is to be read,
otherwise it is to be set. Returns the current value.
protected">@protectedinherited
-
removeTimingsCallback(
TimingsCallback callback) → void - Removes a callback that was earlier added by addTimingsCallback.
-
resetEpoch(
) → void - Prepares the scheduler for a non-monotonic change to how time stamps are calculated.
-
scheduleForcedFrame(
) → void - Schedules a new frame by calling dart:ui.PlatformDispatcher.scheduleFrame.
-
scheduleFrame(
) → void - If necessary, schedules a new frame by calling dart:ui.PlatformDispatcher.scheduleFrame.
-
scheduleFrameCallback(
FrameCallback callback, {bool rescheduling = false}) → int - Schedules the given transient frame callback.
-
scheduleTask<
T> (TaskCallback< T> task, Priority priority, {String? debugLabel, Flow? flow}) → Future<T> -
Schedules the given
taskwith the givenpriorityand returns a Future that completes to thetask's eventual return value. -
scheduleWarmUpFrame(
) → void - Schedule a frame to run as soon as possible, rather than waiting for the engine to request a frame in response to a system "Vsync" signal.
-
toString(
) → String -
A string representation of this object.
inherited
-
unlocked(
) → void -
Called by lockEvents when events get unlocked.
override
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited
Static Properties
- instance → SchedulerBinding
-
The current SchedulerBinding, if one has been created.
read-only
Static Methods
-
debugPrintTransientCallbackRegistrationStack(
) → void - Prints the stack for where the current transient callback was registered.