io.flutter.plugin.common.BinaryMessenger Interface Reference

Inheritance diagram for io.flutter.plugin.common.BinaryMessenger:

Classes
interface	BinaryMessageHandler
interface	BinaryReply
interface	TaskQueue
class	TaskQueueOptions

Public Member Functions
default TaskQueue	makeBackgroundTaskQueue ()
default TaskQueue	makeBackgroundTaskQueue (TaskQueueOptions options)
void	send (@NonNull String channel, @Nullable ByteBuffer message)
void	send (@NonNull String channel, @Nullable ByteBuffer message, @Nullable BinaryReply callback)
void	setMessageHandler (@NonNull String channel, @Nullable BinaryMessageHandler handler)
default void	setMessageHandler ( @NonNull String channel, @Nullable BinaryMessageHandler handler, @Nullable TaskQueue taskQueue)
default void	enableBufferingIncomingMessages ()
default void	disableBufferingIncomingMessages ()

Detailed Description

Facility for communicating with Flutter using asynchronous message passing with binary messages. The Flutter Dart code should use BinaryMessages to participate.

BinaryMessenger is expected to be utilized from a single thread throughout the duration of its existence. If created on the main thread, then all invocations should take place on the main thread. If created on a background thread, then all invocations should take place on that background thread.

See also

BasicMessageChannel , which supports message passing with Strings and semi-structured messages.

MethodChannel , which supports communication using asynchronous method invocation.

EventChannel , which supports communication using event streams.

Definition at line 28 of file BinaryMessenger.java.

Member Function Documentation

disableBufferingIncomingMessages()

default void io.flutter.plugin.common.BinaryMessenger.disableBufferingIncomingMessages ( )

inline

Disables the ability to queue messages received from Dart.

This can be used after all pending channel handlers have been registered.

Implemented in io.flutter.embedding.engine.dart.DartExecutor, io.flutter.embedding.engine.dart.DartMessenger, io.flutter.view.FlutterNativeView, and io.flutter.view.FlutterView.

Definition at line 168 of file BinaryMessenger.java.

                                                  {
    throw new UnsupportedOperationException("disableBufferingIncomingMessages not implemented.");
  }

enableBufferingIncomingMessages()

default void io.flutter.plugin.common.BinaryMessenger.enableBufferingIncomingMessages ( )

inline

Enables the ability to queue messages received from Dart.

This is useful when there are pending channel handler registrations. For example, Dart may be initialized concurrently, and prior to the registration of the channel handlers. This implies that Dart may start sending messages while plugins are being registered.

Implemented in io.flutter.embedding.engine.dart.DartExecutor, io.flutter.embedding.engine.dart.DartMessenger, io.flutter.view.FlutterNativeView, and io.flutter.view.FlutterView.

Definition at line 159 of file BinaryMessenger.java.

                                                 {
    throw new UnsupportedOperationException("enableBufferingIncomingMessages not implemented.");
  }

makeBackgroundTaskQueue() [1/2]

default TaskQueue io.flutter.plugin.common.BinaryMessenger.makeBackgroundTaskQueue ( )

inline

Creates a TaskQueue that executes the tasks serially on a background thread.

There is no guarantee that the tasks will execute on the same thread, just that execution is serial. This is could be problematic if your code relies on ThreadLocal storage or introspection about what thread is actually executing.

Definition at line 67 of file BinaryMessenger.java.

                                              {
    return makeBackgroundTaskQueue(new TaskQueueOptions());
  }

makeBackgroundTaskQueue() [2/2]

default TaskQueue io.flutter.plugin.common.BinaryMessenger.makeBackgroundTaskQueue ( TaskQueueOptions  options )

inline

Creates a TaskQueue that executes the tasks serially on a background thread.

TaskQueueOptions can be used to configure the task queue to execute tasks concurrently. Doing so can be more performant, though users need to ensure that the task handlers are thread-safe.

Implemented in io.flutter.embedding.engine.dart.DartExecutor, io.flutter.embedding.engine.dart.DartMessenger, io.flutter.view.FlutterNativeView, and io.flutter.view.FlutterView.

Definition at line 79 of file BinaryMessenger.java.

                                                                      {
    // TODO(92582): Remove default implementation when it is safe for Google Flutter users.
    throw new UnsupportedOperationException("makeBackgroundTaskQueue not implemented.");
  }

send() [1/2]

void io.flutter.plugin.common.BinaryMessenger.send	(	@NonNull String	channel,
		@Nullable ByteBuffer	message
	)

Sends a binary message to the Flutter application.

Parameters

channel	the name String of the logical channel used for the message.
message	the message payload, a direct-allocated ByteBuffer with the message bytes between position zero and current position, or null.

Implemented in io.flutter.embedding.engine.dart.DartExecutor.

send() [2/2]

void io.flutter.plugin.common.BinaryMessenger.send	(	@NonNull String	channel,
		@Nullable ByteBuffer	message,
		@Nullable BinaryReply	callback
	)

Sends a binary message to the Flutter application, optionally expecting a reply.

Any uncaught exception thrown by the reply callback will be caught and logged.

Parameters

channel	the name String of the logical channel used for the message.
message	the message payload, a direct-allocated ByteBuffer with the message bytes between position zero and current position, or null.
callback	a BinaryReply callback invoked when the Flutter application responds to the message, possibly null.

setMessageHandler() [1/2]

default void io.flutter.plugin.common.BinaryMessenger.setMessageHandler ( @NonNull String  channel, @Nullable BinaryMessageHandler  handler, @Nullable TaskQueue  taskQueue  )

inline

Registers a handler to be invoked when the Flutter application sends a message to its host platform.

Registration overwrites any previous registration for the same channel name. Use a null handler to deregister.

If no handler has been registered for a particular channel, any incoming message on that channel will be handled silently by sending a null reply.

Parameters

channel	the name String of the channel.
handler	a BinaryMessageHandler to be invoked on incoming messages, or null.
taskQueue	a BinaryMessenger.TaskQueue that specifies what thread will execute the handler. Specifying null means execute on the platform thread.

Definition at line 140 of file BinaryMessenger.java.

                                     {
    // TODO(92582): Remove default implementation when it is safe for Google Flutter users.
    if (taskQueue != null) {
      throw new UnsupportedOperationException(
          "setMessageHandler called with nonnull taskQueue is not supported.");
    }
    setMessageHandler(channel, handler);
  }

setMessageHandler() [2/2]

void io.flutter.plugin.common.BinaryMessenger.setMessageHandler	(	@NonNull String	channel,
		@Nullable BinaryMessageHandler	handler
	)

Registers a handler to be invoked when the Flutter application sends a message to its host platform.

Registration overwrites any previous registration for the same channel name. Use a null handler to deregister.

If no handler has been registered for a particular channel, any incoming message on that channel will be handled silently by sending a null reply.

Parameters

channel	the name String of the channel.
handler	a BinaryMessageHandler to be invoked on incoming messages, or null.

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The documentation for this interface was generated from the following file:

• shell/platform/android/io/flutter/plugin/common/BinaryMessenger.java