Package io.flutter.embedding.engine.renderer

Class FlutterRenderer

java.lang.Object

io.flutter.embedding.engine.renderer.FlutterRenderer

All Implemented Interfaces:

TextureRegistry

public class FlutterRenderer
extends Object
implements TextureRegistry

Represents the rendering responsibilities of a FlutterEngine.

FlutterRenderer works in tandem with a provided RenderSurface to paint Flutter pixels to an Android View hierarchy.

FlutterRenderer manages textures for rendering, and forwards some Java calls to native Flutter code via JNI. The corresponding RenderSurface provides the Android Surface that this renderer paints.

FlutterSurfaceView and FlutterTextureView are implementations of RenderSurface.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	FlutterRenderer.DisplayFeature	Description of a physical feature on the display.
static class	FlutterRenderer.DisplayFeatureState	State of the display feature.
static class	FlutterRenderer.DisplayFeatureType	Types of display features that can appear on the viewport.
static class	FlutterRenderer.ViewportMetrics	Mutable data structure that holds all viewport metrics properties that Flutter cares about.

Nested classes/interfaces inherited from interface io.flutter.view.TextureRegistry

TextureRegistry.OnFrameConsumedListener, TextureRegistry.OnTrimMemoryListener, TextureRegistry.SurfaceTextureEntry

Constructor Summary

Constructors

Constructor	Description
FlutterRenderer(FlutterJNI flutterJNI)

Method Summary

Modifier and Type	Method	Description
void	addIsDisplayingFlutterUiListener(FlutterUiDisplayListener listener)	Adds a listener that is invoked whenever this FlutterRenderer starts and stops painting pixels to an Android View hierarchy.
TextureRegistry.SurfaceTextureEntry	createSurfaceTexture()	Creates and returns a new SurfaceTexture managed by the Flutter engine that is also made available to Flutter code.
void	dispatchPointerDataPacket(ByteBuffer buffer, int position)
void	dispatchSemanticsAction(int id, int action, ByteBuffer args, int argsPosition)
Bitmap	getBitmap()
boolean	isDisplayingFlutterUi()	Returns true if this FlutterRenderer is painting pixels to an Android View hierarchy, false otherwise.
boolean	isSoftwareRenderingEnabled()
void	onTrimMemory(int level)	Callback invoked when memory is low.
TextureRegistry.SurfaceTextureEntry	registerSurfaceTexture(SurfaceTexture surfaceTexture)	Registers and returns a SurfaceTexture managed by the Flutter engine that is also made available to Flutter code.
void	removeIsDisplayingFlutterUiListener(FlutterUiDisplayListener listener)	Removes a listener added via addIsDisplayingFlutterUiListener(FlutterUiDisplayListener).
void	setAccessibilityFeatures(int flags)
void	setSemanticsEnabled(boolean enabled)
void	setViewportMetrics(FlutterRenderer.ViewportMetrics viewportMetrics)	Notifies Flutter that the viewport metrics, e.g.
void	startRenderingToSurface(Surface surface, boolean keepCurrentSurface)	Notifies Flutter that the given surface was created and is available for Flutter rendering.
void	stopRenderingToSurface()	Notifies Flutter that a surface previously registered with startRenderingToSurface(Surface, boolean) has been destroyed and needs to be released and cleaned up on the Flutter side.
void	surfaceChanged(int width, int height)	Notifies Flutter that a surface previously registered with startRenderingToSurface(Surface, boolean) has changed size to the given width and height.
void	swapSurface(Surface surface)	Swaps the Surface used to render the current frame.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

FlutterRenderer

public FlutterRenderer(@NonNull
                       FlutterJNI flutterJNI)

Method Detail

isDisplayingFlutterUi

public boolean isDisplayingFlutterUi()

Returns true if this FlutterRenderer is painting pixels to an Android View hierarchy, false otherwise.

addIsDisplayingFlutterUiListener

public void addIsDisplayingFlutterUiListener(@NonNull
                                             FlutterUiDisplayListener listener)

Adds a listener that is invoked whenever this FlutterRenderer starts and stops painting pixels to an Android View hierarchy.

removeIsDisplayingFlutterUiListener

public void removeIsDisplayingFlutterUiListener(@NonNull
                                                FlutterUiDisplayListener listener)

Removes a listener added via addIsDisplayingFlutterUiListener(FlutterUiDisplayListener).

createSurfaceTexture

public TextureRegistry.SurfaceTextureEntry createSurfaceTexture()

Creates and returns a new SurfaceTexture managed by the Flutter engine that is also made available to Flutter code.

Specified by:

createSurfaceTexture in interface TextureRegistry

Returns:

A SurfaceTextureEntry.

registerSurfaceTexture

public TextureRegistry.SurfaceTextureEntry registerSurfaceTexture(@NonNull
                                                                  SurfaceTexture surfaceTexture)

Registers and returns a SurfaceTexture managed by the Flutter engine that is also made available to Flutter code.

Specified by:

registerSurfaceTexture in interface TextureRegistry

Returns:

A SurfaceTextureEntry.

onTrimMemory

public void onTrimMemory(int level)

Description copied from interface: TextureRegistry

Callback invoked when memory is low.

Invoke this from Activity.onTrimMemory(int).

Specified by:

onTrimMemory in interface TextureRegistry

startRenderingToSurface

public void startRenderingToSurface(@NonNull
                                    Surface surface,
                                    boolean keepCurrentSurface)

Notifies Flutter that the given surface was created and is available for Flutter rendering.

If called more than once, the current native resources are released. This can be undesired if the Engine expects to reuse this surface later. For example, this is true when platform views are displayed in a frame, and then removed in the next frame.

To avoid releasing the current surface resources, set keepCurrentSurface to true.

See SurfaceHolder.Callback and TextureView.SurfaceTextureListener

Parameters:

surface - The render surface.

keepCurrentSurface - True if the current active surface should not be released.

swapSurface

public void swapSurface(@NonNull
                        Surface surface)

Swaps the Surface used to render the current frame.

In hybrid composition, the root surfaces changes from SurfaceHolder.getSurface() to ImageReader.getSurface() when a platform view is in the current frame.

surfaceChanged

public void surfaceChanged(int width,
                           int height)

Notifies Flutter that a surface previously registered with startRenderingToSurface(Surface, boolean) has changed size to the given width and height.

See SurfaceHolder.Callback and TextureView.SurfaceTextureListener

stopRenderingToSurface

public void stopRenderingToSurface()

Notifies Flutter that a surface previously registered with startRenderingToSurface(Surface, boolean) has been destroyed and needs to be released and cleaned up on the Flutter side.

See SurfaceHolder.Callback and TextureView.SurfaceTextureListener

setViewportMetrics

public void setViewportMetrics(@NonNull
                               FlutterRenderer.ViewportMetrics viewportMetrics)

Notifies Flutter that the viewport metrics, e.g. window height and width, have changed.

If the width, height, or devicePixelRatio are less than or equal to 0, this update is ignored.

Parameters:

viewportMetrics - The metrics to send to the Dart application.

getBitmap

public Bitmap getBitmap()

dispatchPointerDataPacket

public void dispatchPointerDataPacket(@NonNull
                                      ByteBuffer buffer,
                                      int position)

isSoftwareRenderingEnabled

public boolean isSoftwareRenderingEnabled()

setAccessibilityFeatures

public void setAccessibilityFeatures(int flags)

setSemanticsEnabled

public void setSemanticsEnabled(boolean enabled)

dispatchSemanticsAction

public void dispatchSemanticsAction(int id,
                                    int action,
                                    @Nullable
                                    ByteBuffer args,
                                    int argsPosition)