blob: 679b3692c087bf61135003df13a810f039f78bd8 [file] [log] [blame]
// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'dart:async';
import 'dart:ui';
import 'package:flutter/foundation.dart';
import 'package:flutter/gestures.dart';
import 'package:flutter/semantics.dart';
import 'package:flutter/services.dart';
import 'box.dart';
import 'layer.dart';
import 'mouse_tracking.dart';
import 'object.dart';
/// How an embedded platform view behave during hit tests.
enum PlatformViewHitTestBehavior {
/// Opaque targets can be hit by hit tests, causing them to both receive
/// events within their bounds and prevent targets visually behind them from
/// also receiving events.
opaque,
/// Translucent targets both receive events within their bounds and permit
/// targets visually behind them to also receive events.
translucent,
/// Transparent targets don't receive events within their bounds and permit
/// targets visually behind them to receive events.
transparent,
}
enum _PlatformViewState {
uninitialized,
resizing,
ready,
}
bool _factoryTypesSetEquals<T>(Set<Factory<T>> a, Set<Factory<T>> b) {
if (a == b) {
return true;
}
if (a == null || b == null) {
return false;
}
return setEquals(_factoriesTypeSet(a), _factoriesTypeSet(b));
}
Set<Type> _factoriesTypeSet<T>(Set<Factory<T>> factories) {
return factories.map<Type>((Factory<T> factory) => factory.type).toSet();
}
/// A render object for an Android view.
///
/// Requires Android API level 20 or greater.
///
/// [RenderAndroidView] is responsible for sizing, displaying and passing touch events to an
/// Android [View](https://developer.android.com/reference/android/view/View).
///
/// {@template flutter.rendering.platformView.layout}
/// The render object's layout behavior is to fill all available space, the parent of this object must
/// provide bounded layout constraints.
/// {@endtemplate}
///
/// {@template flutter.rendering.platformView.gestures}
/// The render object participates in Flutter's [GestureArena]s, and dispatches touch events to the
/// platform view iff it won the arena. Specific gestures that should be dispatched to the platform
/// view can be specified with factories in the `gestureRecognizers` constructor parameter or
/// by calling `updateGestureRecognizers`. If the set of gesture recognizers is empty, the gesture
/// will be dispatched to the platform view iff it was not claimed by any other gesture recognizer.
/// {@endtemplate}
///
/// See also:
///
/// * [AndroidView] which is a widget that is used to show an Android view.
/// * [PlatformViewsService] which is a service for controlling platform views.
class RenderAndroidView extends RenderBox with _PlatformViewGestureMixin {
/// Creates a render object for an Android view.
RenderAndroidView({
@required AndroidViewController viewController,
@required PlatformViewHitTestBehavior hitTestBehavior,
@required Set<Factory<OneSequenceGestureRecognizer>> gestureRecognizers,
}) : assert(viewController != null),
assert(hitTestBehavior != null),
assert(gestureRecognizers != null),
_viewController = viewController {
_motionEventsDispatcher = _MotionEventsDispatcher(globalToLocal, viewController);
updateGestureRecognizers(gestureRecognizers);
_viewController.addOnPlatformViewCreatedListener(_onPlatformViewCreated);
this.hitTestBehavior = hitTestBehavior;
}
_PlatformViewState _state = _PlatformViewState.uninitialized;
/// The Android view controller for the Android view associated with this render object.
AndroidViewController get viewcontroller => _viewController;
AndroidViewController _viewController;
/// Sets a new Android view controller.
///
/// `viewController` must not be null.
set viewController(AndroidViewController viewController) {
assert(_viewController != null);
assert(viewController != null);
if (_viewController == viewController)
return;
_viewController.removeOnPlatformViewCreatedListener(_onPlatformViewCreated);
_viewController = viewController;
_sizePlatformView();
if (_viewController.isCreated) {
markNeedsSemanticsUpdate();
}
_viewController.addOnPlatformViewCreatedListener(_onPlatformViewCreated);
}
void _onPlatformViewCreated(int id) {
markNeedsSemanticsUpdate();
}
/// {@template flutter.rendering.platformView.updateGestureRecognizers}
/// Updates which gestures should be forwarded to the platform view.
///
/// Gesture recognizers created by factories in this set participate in the gesture arena for each
/// pointer that was put down on the render box. If any of the recognizers on this list wins the
/// gesture arena, the entire pointer event sequence starting from the pointer down event
/// will be dispatched to the Android view.
///
/// The `gestureRecognizers` property must not contain more than one factory with the same [Factory.type].
///
/// Setting a new set of gesture recognizer factories with the same [Factory.type]s as the current
/// set has no effect, because the factories' constructors would have already been called with the previous set.
/// {@endtemplate}
///
/// Any active gesture arena the Android view participates in is rejected when the
/// set of gesture recognizers is changed.
void updateGestureRecognizers(Set<Factory<OneSequenceGestureRecognizer>> gestureRecognizers) {
_updateGestureRecognizersWithCallBack(gestureRecognizers, _motionEventsDispatcher.handlePointerEvent);
}
@override
bool get sizedByParent => true;
@override
bool get alwaysNeedsCompositing => true;
@override
bool get isRepaintBoundary => true;
_MotionEventsDispatcher _motionEventsDispatcher;
@override
void performResize() {
size = constraints.biggest;
_sizePlatformView();
}
Size _currentAndroidViewSize;
Future<void> _sizePlatformView() async {
// Android virtual displays cannot have a zero size.
// Trying to size it to 0 crashes the app, which was happening when starting the app
// with a locked screen (see: https://github.com/flutter/flutter/issues/20456).
if (_state == _PlatformViewState.resizing || size.isEmpty) {
return;
}
_state = _PlatformViewState.resizing;
markNeedsPaint();
Size targetSize;
do {
targetSize = size;
await _viewController.setSize(targetSize);
_currentAndroidViewSize = targetSize;
// We've resized the platform view to targetSize, but it is possible that
// while we were resizing the render object's size was changed again.
// In that case we will resize the platform view again.
} while (size != targetSize);
_state = _PlatformViewState.ready;
markNeedsPaint();
}
@override
void paint(PaintingContext context, Offset offset) {
if (_viewController.textureId == null)
return;
// Clip the texture if it's going to paint out of the bounds of the renter box
// (see comment in _paintTexture for an explanation of when this happens).
if (size.width < _currentAndroidViewSize.width || size.height < _currentAndroidViewSize.height) {
context.pushClipRect(true, offset, offset & size, _paintTexture);
return;
}
_paintTexture(context, offset);
}
void _paintTexture(PaintingContext context, Offset offset) {
// As resizing the Android view happens asynchronously we don't know exactly when is a
// texture frame with the new size is ready for consumption.
// TextureLayer is unaware of the texture frame's size and always maps it to the
// specified rect. If the rect we provide has a different size from the current texture frame's
// size the texture frame will be scaled.
// To prevent unwanted scaling artifacts while resizing we freeze the texture frame, until
// we know that a frame with the new size is in the buffer.
// This guarantees that the size of the texture frame we're painting is always
// _currentAndroidViewSize.
context.addLayer(TextureLayer(
rect: offset & _currentAndroidViewSize,
textureId: _viewController.textureId,
freeze: _state == _PlatformViewState.resizing,
));
}
@override
void describeSemanticsConfiguration (SemanticsConfiguration config) {
super.describeSemanticsConfiguration(config);
config.isSemanticBoundary = true;
if (_viewController.isCreated) {
config.platformViewId = _viewController.id;
}
}
}
/// A render object for an iOS UIKit UIView.
///
/// {@template flutter.rendering.platformView.preview}
/// Embedding UIViews is still in release preview, to enable the preview for an iOS app add a boolean
/// field with the key 'io.flutter.embedded_views_preview' and the value set to 'YES' to the
/// application's Info.plist file. A list of open issued with embedding UIViews is available on
/// [Github](https://github.com/flutter/flutter/issues?q=is%3Aopen+is%3Aissue+label%3A%22a%3A+platform-views%22+label%3A%22%E2%8C%BA%E2%80%AC+platform-ios%22)
/// {@endtemplate}
///
/// [RenderUiKitView] is responsible for sizing and displaying an iOS
/// [UIView](https://developer.apple.com/documentation/uikit/uiview).
///
/// UIViews are added as sub views of the FlutterView and are composited by Quartz.
///
/// {@macro flutter.rendering.platformView.layout}
///
/// {@macro flutter.rendering.platformView.gestures}
///
/// See also:
///
/// * [UiKitView] which is a widget that is used to show a UIView.
/// * [PlatformViewsService] which is a service for controlling platform views.
class RenderUiKitView extends RenderBox {
/// Creates a render object for an iOS UIView.
///
/// The `viewId`, `hitTestBehavior`, and `gestureRecognizers` parameters must not be null.
RenderUiKitView({
@required UiKitViewController viewController,
@required this.hitTestBehavior,
@required Set<Factory<OneSequenceGestureRecognizer>> gestureRecognizers,
}) : assert(viewController != null),
assert(hitTestBehavior != null),
assert(gestureRecognizers != null),
_viewController = viewController {
updateGestureRecognizers(gestureRecognizers);
}
/// The unique identifier of the UIView controlled by this controller.
///
/// Typically generated by [PlatformViewsRegistry.getNextPlatformViewId], the UIView
/// must have been created by calling [PlatformViewsService.initUiKitView].
UiKitViewController get viewController => _viewController;
UiKitViewController _viewController;
set viewController(UiKitViewController viewController) {
assert(viewController != null);
final bool needsSemanticsUpdate = _viewController.id != viewController.id;
_viewController = viewController;
markNeedsPaint();
if (needsSemanticsUpdate) {
markNeedsSemanticsUpdate();
}
}
/// How to behave during hit testing.
// The implicit setter is enough here as changing this value will just affect
// any newly arriving events there's nothing we need to invalidate.
PlatformViewHitTestBehavior hitTestBehavior;
/// {@macro flutter.rendering.platformView.updateGestureRecognizers}
void updateGestureRecognizers(Set<Factory<OneSequenceGestureRecognizer>> gestureRecognizers) {
assert(gestureRecognizers != null);
assert(
_factoriesTypeSet(gestureRecognizers).length == gestureRecognizers.length,
'There were multiple gesture recognizer factories for the same type, there must only be a single '
'gesture recognizer factory for each gesture recognizer type.',);
if (_factoryTypesSetEquals(gestureRecognizers, _gestureRecognizer?.gestureRecognizerFactories)) {
return;
}
_gestureRecognizer?.dispose();
_gestureRecognizer = _UiKitViewGestureRecognizer(viewController, gestureRecognizers);
}
@override
bool get sizedByParent => true;
@override
bool get alwaysNeedsCompositing => true;
@override
bool get isRepaintBoundary => true;
_UiKitViewGestureRecognizer _gestureRecognizer;
PointerEvent _lastPointerDownEvent;
@override
void performResize() {
size = constraints.biggest;
}
@override
void paint(PaintingContext context, Offset offset) {
context.addLayer(PlatformViewLayer(
rect: offset & size,
viewId: _viewController.id,
));
}
@override
bool hitTest(BoxHitTestResult result, { Offset position }) {
if (hitTestBehavior == PlatformViewHitTestBehavior.transparent || !size.contains(position))
return false;
result.add(BoxHitTestEntry(this, position));
return hitTestBehavior == PlatformViewHitTestBehavior.opaque;
}
@override
bool hitTestSelf(Offset position) => hitTestBehavior != PlatformViewHitTestBehavior.transparent;
@override
void handleEvent(PointerEvent event, HitTestEntry entry) {
if (event is! PointerDownEvent) {
return;
}
_gestureRecognizer.addPointer(event as PointerDownEvent);
_lastPointerDownEvent = event.original ?? event;
}
// This is registered as a global PointerRoute while the render object is attached.
void _handleGlobalPointerEvent(PointerEvent event) {
if (event is! PointerDownEvent) {
return;
}
if (!(Offset.zero & size).contains(globalToLocal(event.position))) {
return;
}
if ((event.original ?? event) != _lastPointerDownEvent) {
// The pointer event is in the bounds of this render box, but we didn't get it in handleEvent.
// This means that the pointer event was absorbed by a different render object.
// Since on the platform side the FlutterTouchIntercepting view is seeing all events that are
// within its bounds we need to tell it to reject the current touch sequence.
_viewController.rejectGesture();
}
_lastPointerDownEvent = null;
}
@override
void describeSemanticsConfiguration (SemanticsConfiguration config) {
super.describeSemanticsConfiguration(config);
config.isSemanticBoundary = true;
config.platformViewId = _viewController.id;
}
@override
void attach(PipelineOwner owner) {
super.attach(owner);
GestureBinding.instance.pointerRouter.addGlobalRoute(_handleGlobalPointerEvent);
}
@override
void detach() {
GestureBinding.instance.pointerRouter.removeGlobalRoute(_handleGlobalPointerEvent);
_gestureRecognizer.reset();
super.detach();
}
}
// This recognizer constructs gesture recognizers from a set of gesture recognizer factories
// it was give, adds all of them to a gesture arena team with the _UiKitViewGesturrRecognizer
// as the team captain.
// When the team wins a gesture the recognizer notifies the engine that it should release
// the touch sequence to the embedded UIView.
class _UiKitViewGestureRecognizer extends OneSequenceGestureRecognizer {
_UiKitViewGestureRecognizer(
this.controller,
this.gestureRecognizerFactories, {
PointerDeviceKind kind,
}) : super(kind: kind) {
team = GestureArenaTeam();
team.captain = this;
_gestureRecognizers = gestureRecognizerFactories.map(
(Factory<OneSequenceGestureRecognizer> recognizerFactory) {
return recognizerFactory.constructor()..team = team;
},
).toSet();
}
// We use OneSequenceGestureRecognizers as they support gesture arena teams.
// TODO(amirh): get a list of GestureRecognizers here.
// https://github.com/flutter/flutter/issues/20953
final Set<Factory<OneSequenceGestureRecognizer>> gestureRecognizerFactories;
Set<OneSequenceGestureRecognizer> _gestureRecognizers;
final UiKitViewController controller;
@override
void addAllowedPointer(PointerDownEvent event) {
startTrackingPointer(event.pointer, event.transform);
for (final OneSequenceGestureRecognizer recognizer in _gestureRecognizers) {
recognizer.addPointer(event);
}
}
@override
String get debugDescription => 'UIKit view';
@override
void didStopTrackingLastPointer(int pointer) { }
@override
void handleEvent(PointerEvent event) {
stopTrackingIfPointerNoLongerDown(event);
}
@override
void acceptGesture(int pointer) {
controller.acceptGesture();
}
@override
void rejectGesture(int pointer) {
controller.rejectGesture();
}
void reset() {
resolve(GestureDisposition.rejected);
}
}
typedef _HandlePointerEvent = void Function(PointerEvent event);
// This recognizer constructs gesture recognizers from a set of gesture recognizer factories
// it was give, adds all of them to a gesture arena team with the _PlatformViewGestureRecognizer
// as the team captain.
// As long as the gesture arena is unresolved, the recognizer caches all pointer events.
// When the team wins, the recognizer sends all the cached pointer events to `_handlePointerEvent`, and
// sets itself to a "forwarding mode" where it will forward any new pointer event to `_handlePointerEvent`.
class _PlatformViewGestureRecognizer extends OneSequenceGestureRecognizer {
_PlatformViewGestureRecognizer(
_HandlePointerEvent handlePointerEvent,
this.gestureRecognizerFactories, {
PointerDeviceKind kind,
}) : super(kind: kind) {
team = GestureArenaTeam();
team.captain = this;
_gestureRecognizers = gestureRecognizerFactories.map(
(Factory<OneSequenceGestureRecognizer> recognizerFactory) {
return recognizerFactory.constructor()..team = team;
},
).toSet();
_handlePointerEvent = handlePointerEvent;
}
_HandlePointerEvent _handlePointerEvent;
// Maps a pointer to a list of its cached pointer events.
// Before the arena for a pointer is resolved all events are cached here, if we win the arena
// the cached events are dispatched to `_handlePointerEvent`, if we lose the arena we clear the cache for
// the pointer.
final Map<int, List<PointerEvent>> cachedEvents = <int, List<PointerEvent>>{};
// Pointer for which we have already won the arena, events for pointers in this set are
// immediately dispatched to `_handlePointerEvent`.
final Set<int> forwardedPointers = <int>{};
// We use OneSequenceGestureRecognizers as they support gesture arena teams.
// TODO(amirh): get a list of GestureRecognizers here.
// https://github.com/flutter/flutter/issues/20953
final Set<Factory<OneSequenceGestureRecognizer>> gestureRecognizerFactories;
Set<OneSequenceGestureRecognizer> _gestureRecognizers;
@override
void addAllowedPointer(PointerDownEvent event) {
startTrackingPointer(event.pointer, event.transform);
for (final OneSequenceGestureRecognizer recognizer in _gestureRecognizers) {
recognizer.addPointer(event);
}
}
@override
String get debugDescription => 'Platform view';
@override
void didStopTrackingLastPointer(int pointer) { }
@override
void handleEvent(PointerEvent event) {
if (!forwardedPointers.contains(event.pointer)) {
_cacheEvent(event);
} else {
_handlePointerEvent(event);
}
stopTrackingIfPointerNoLongerDown(event);
}
@override
void acceptGesture(int pointer) {
_flushPointerCache(pointer);
forwardedPointers.add(pointer);
}
@override
void rejectGesture(int pointer) {
stopTrackingPointer(pointer);
cachedEvents.remove(pointer);
}
void _cacheEvent(PointerEvent event) {
if (!cachedEvents.containsKey(event.pointer)) {
cachedEvents[event.pointer] = <PointerEvent> [];
}
cachedEvents[event.pointer].add(event);
}
void _flushPointerCache(int pointer) {
cachedEvents.remove(pointer)?.forEach(_handlePointerEvent);
}
@override
void stopTrackingPointer(int pointer) {
super.stopTrackingPointer(pointer);
forwardedPointers.remove(pointer);
}
void reset() {
forwardedPointers.forEach(super.stopTrackingPointer);
forwardedPointers.clear();
cachedEvents.keys.forEach(super.stopTrackingPointer);
cachedEvents.clear();
resolve(GestureDisposition.rejected);
}
}
typedef _GlobalToLocal = Offset Function(Offset point);
// Composes a stream of PointerEvent objects into AndroidMotionEvent objects
// and dispatches them to the associated embedded Android view.
class _MotionEventsDispatcher {
_MotionEventsDispatcher(this.globalToLocal, this.viewController);
final Map<int, AndroidPointerCoords> pointerPositions = <int, AndroidPointerCoords>{};
final Map<int, AndroidPointerProperties> pointerProperties = <int, AndroidPointerProperties>{};
final _GlobalToLocal globalToLocal;
final AndroidViewController viewController;
int nextPointerId = 0;
int downTimeMillis;
void handlePointerEvent(PointerEvent event) {
if (event is PointerDownEvent) {
if (nextPointerId == 0)
downTimeMillis = event.timeStamp.inMilliseconds;
pointerProperties[event.pointer] = propertiesFor(event, nextPointerId++);
}
pointerPositions[event.pointer] = coordsFor(event);
dispatchPointerEvent(event);
if (event is PointerUpEvent) {
pointerPositions.remove(event.pointer);
pointerProperties.remove(event.pointer);
if (pointerProperties.isEmpty) {
nextPointerId = 0;
downTimeMillis = null;
}
}
if (event is PointerCancelEvent) {
pointerPositions.clear();
pointerProperties.clear();
nextPointerId = 0;
downTimeMillis = null;
}
}
void dispatchPointerEvent(PointerEvent event) {
final List<int> pointers = pointerPositions.keys.toList();
final int pointerIdx = pointers.indexOf(event.pointer);
final int numPointers = pointers.length;
// This value must match the value in engine's FlutterView.java.
// This flag indicates whether the original Android pointer events were batched together.
const int kPointerDataFlagBatched = 1;
// Android MotionEvent objects can batch information on multiple pointers.
// Flutter breaks these such batched events into multiple PointerEvent objects.
// When there are multiple active pointers we accumulate the information for all pointers
// as we get PointerEvents, and only send it to the embedded Android view when
// we see the last pointer. This way we achieve the same batching as Android.
if (event.platformData == kPointerDataFlagBatched ||
(isSinglePointerAction(event) && pointerIdx < numPointers - 1))
return;
int action;
switch (event.runtimeType) {
case PointerDownEvent:
action = numPointers == 1 ? AndroidViewController.kActionDown
: AndroidViewController.pointerAction(pointerIdx, AndroidViewController.kActionPointerDown);
break;
case PointerUpEvent:
action = numPointers == 1 ? AndroidViewController.kActionUp
: AndroidViewController.pointerAction(pointerIdx, AndroidViewController.kActionPointerUp);
break;
case PointerMoveEvent:
action = AndroidViewController.kActionMove;
break;
case PointerCancelEvent:
action = AndroidViewController.kActionCancel;
break;
default:
return;
}
final AndroidMotionEvent androidMotionEvent = AndroidMotionEvent(
downTime: downTimeMillis,
eventTime: event.timeStamp.inMilliseconds,
action: action,
pointerCount: pointerPositions.length,
pointerProperties: pointers.map<AndroidPointerProperties>((int i) => pointerProperties[i]).toList(),
pointerCoords: pointers.map<AndroidPointerCoords>((int i) => pointerPositions[i]).toList(),
metaState: 0,
buttonState: 0,
xPrecision: 1.0,
yPrecision: 1.0,
deviceId: 0,
edgeFlags: 0,
source: 0,
flags: 0,
);
viewController.sendMotionEvent(androidMotionEvent);
}
AndroidPointerCoords coordsFor(PointerEvent event) {
final Offset position = globalToLocal(event.position);
return AndroidPointerCoords(
orientation: event.orientation,
pressure: event.pressure,
size: event.size,
toolMajor: event.radiusMajor,
toolMinor: event.radiusMinor,
touchMajor: event.radiusMajor,
touchMinor: event.radiusMinor,
x: position.dx,
y: position.dy,
);
}
AndroidPointerProperties propertiesFor(PointerEvent event, int pointerId) {
int toolType = AndroidPointerProperties.kToolTypeUnknown;
switch(event.kind) {
case PointerDeviceKind.touch:
toolType = AndroidPointerProperties.kToolTypeFinger;
break;
case PointerDeviceKind.mouse:
toolType = AndroidPointerProperties.kToolTypeMouse;
break;
case PointerDeviceKind.stylus:
toolType = AndroidPointerProperties.kToolTypeStylus;
break;
case PointerDeviceKind.invertedStylus:
toolType = AndroidPointerProperties.kToolTypeEraser;
break;
case PointerDeviceKind.unknown:
toolType = AndroidPointerProperties.kToolTypeUnknown;
break;
}
return AndroidPointerProperties(id: pointerId, toolType: toolType);
}
bool isSinglePointerAction(PointerEvent event) => event is! PointerDownEvent && event is! PointerUpEvent;
}
/// A render object for embedding a platform view.
///
/// [PlatformViewRenderBox] presents a platform view by adding a [PlatformViewLayer] layer,
/// integrates it with the gesture arenas system and adds relevant semantic nodes to the semantics tree.
class PlatformViewRenderBox extends RenderBox with _PlatformViewGestureMixin {
/// Creating a render object for a [PlatformViewSurface].
///
/// The `controller` parameter must not be null.
PlatformViewRenderBox({
@required PlatformViewController controller,
@required PlatformViewHitTestBehavior hitTestBehavior,
@required Set<Factory<OneSequenceGestureRecognizer>> gestureRecognizers,
}) : assert(controller != null && controller.viewId != null && controller.viewId > -1),
assert(hitTestBehavior != null),
assert(gestureRecognizers != null),
_controller = controller {
this.hitTestBehavior = hitTestBehavior;
updateGestureRecognizers(gestureRecognizers);
}
/// Sets the [controller] for this render object.
///
/// This value must not be null, and setting it to a new value will result in a repaint.
set controller(PlatformViewController controller) {
assert(controller != null);
assert(controller.viewId != null && controller.viewId > -1);
if ( _controller == controller) {
return;
}
final bool needsSemanticsUpdate = _controller.viewId != controller.viewId;
_controller = controller;
markNeedsPaint();
if (needsSemanticsUpdate) {
markNeedsSemanticsUpdate();
}
}
/// {@macro flutter.rendering.platformView.updateGestureRecognizers}
///
/// Any active gesture arena the `PlatformView` participates in is rejected when the
/// set of gesture recognizers is changed.
void updateGestureRecognizers(Set<Factory<OneSequenceGestureRecognizer>> gestureRecognizers) {
_updateGestureRecognizersWithCallBack(gestureRecognizers, _controller.dispatchPointerEvent);
}
PlatformViewController _controller;
@override
bool get sizedByParent => true;
@override
bool get alwaysNeedsCompositing => true;
@override
bool get isRepaintBoundary => true;
@override
void performResize() {
size = constraints.biggest;
}
@override
void paint(PaintingContext context, Offset offset) {
assert(_controller.viewId != null);
context.addLayer(PlatformViewLayer(
rect: offset & size,
viewId: _controller.viewId,
hoverAnnotation: _hoverAnnotation));
}
@override
void describeSemanticsConfiguration (SemanticsConfiguration config) {
super.describeSemanticsConfiguration(config);
assert(_controller.viewId != null);
config.isSemanticBoundary = true;
config.platformViewId = _controller.viewId;
}
}
/// The Mixin handling the pointer events and gestures of a platform view render box.
mixin _PlatformViewGestureMixin on RenderBox {
/// How to behave during hit testing.
// The implicit setter is enough here as changing this value will just affect
// any newly arriving events there's nothing we need to invalidate.
PlatformViewHitTestBehavior hitTestBehavior;
/// [MouseTrackerAnnotation] associated with the platform view layer.
///
/// Gesture recognizers don't receive hover events due to the performance
/// cost associated with hit testing a sequence of potentially thousands of
/// events -- move events only hit-test the down event, then cache the result
/// and apply it to all subsequent move events, but there is no down event
/// for a hover. To support native hover gesture handling by platform views,
/// we attach/detach this layer annotation as necessary.
MouseTrackerAnnotation _hoverAnnotation;
_HandlePointerEvent _handlePointerEvent;
/// {@macro flutter.rendering.platformView.updateGestureRecognizers}
///
/// Any active gesture arena the `PlatformView` participates in is rejected when the
/// set of gesture recognizers is changed.
void _updateGestureRecognizersWithCallBack(Set<Factory<OneSequenceGestureRecognizer>> gestureRecognizers, _HandlePointerEvent handlePointerEvent) {
assert(gestureRecognizers != null);
assert(
_factoriesTypeSet(gestureRecognizers).length == gestureRecognizers.length,
'There were multiple gesture recognizer factories for the same type, there must only be a single '
'gesture recognizer factory for each gesture recognizer type.',);
if (_factoryTypesSetEquals(gestureRecognizers, _gestureRecognizer?.gestureRecognizerFactories)) {
return;
}
_gestureRecognizer?.dispose();
_gestureRecognizer = _PlatformViewGestureRecognizer(handlePointerEvent, gestureRecognizers);
_handlePointerEvent = handlePointerEvent;
}
_PlatformViewGestureRecognizer _gestureRecognizer;
@override
bool hitTest(BoxHitTestResult result, { Offset position }) {
if (hitTestBehavior == PlatformViewHitTestBehavior.transparent || !size.contains(position)) {
return false;
}
result.add(BoxHitTestEntry(this, position));
return hitTestBehavior == PlatformViewHitTestBehavior.opaque;
}
@override
bool hitTestSelf(Offset position) => hitTestBehavior != PlatformViewHitTestBehavior.transparent;
@override
void handleEvent(PointerEvent event, HitTestEntry entry) {
if (event is PointerDownEvent) {
_gestureRecognizer.addPointer(event);
}
}
@override
void attach(PipelineOwner owner) {
super.attach(owner);
assert(_hoverAnnotation == null);
_hoverAnnotation = MouseTrackerAnnotation(onHover: (PointerHoverEvent event) {
if (_handlePointerEvent != null)
_handlePointerEvent(event);
});
}
@override
void detach() {
_gestureRecognizer.reset();
_hoverAnnotation = null;
super.detach();
}
}