FlutterBasicMessageChannel Class Reference

#import <FlutterChannels.h>

Inheritance diagram for FlutterBasicMessageChannel:

Instance Methods
(instancetype)	- initWithName:binaryMessenger:codec:
(instancetype)	- initWithName:binaryMessenger:codec:taskQueue:
(void)	- sendMessage:
(void)	- sendMessage:reply:
(void)	- setMessageHandler:
(void)	- resizeChannelBuffer:
(void)	- setWarnsOnOverflow:
(instancetype)	- initWithName:binaryMessenger:codec:taskQueue: [implementation]
(void)	- sendMessage: [implementation]
(void)	- sendMessage:reply: [implementation]
(void)	- setMessageHandler: [implementation]

Class Methods
(instancetype)	+ messageChannelWithName:binaryMessenger:
(instancetype)	+ messageChannelWithName:binaryMessenger:codec:
(void)	+ resizeChannelWithName:binaryMessenger:size:
(void)	+ setWarnsOnOverflow:forChannelWithName:binaryMessenger:

Detailed Description

A channel for communicating with the Flutter side using basic, asynchronous message passing.

Definition at line 37 of file FlutterChannels.h.

Method Documentation

initWithName:binaryMessenger:codec:

- (instancetype) initWithName:		(NSString*)	name
binaryMessenger:		(NSObject<FlutterBinaryMessenger>*)	messenger
codec:		(NSObject<FlutterMessageCodec>*)	codec

Initializes a FlutterBasicMessageChannel with the specified name, binary messenger, and message codec.

The channel name logically identifies the channel; identically named channels interfere with each other's communication.

The binary messenger is a facility for sending raw, binary messages to the Flutter side. This protocol is implemented by FlutterEngine and FlutterViewController.

Parameters

name	The channel name.
messenger	The binary messenger.
codec	The message codec.

Definition at line 73 of file FlutterChannels.mm.

                            :(NSString*)name
             binaryMessenger:(NSObject<FlutterBinaryMessenger>*)messenger
                       codec:(NSObject<FlutterMessageCodec>*)codec {
  self = [self initWithName:name binaryMessenger:messenger codec:codec taskQueue:nil];
  return self;
}

initWithName:binaryMessenger:codec:taskQueue: [1/2]

- (instancetype) initWithName: (NSString*)  name binaryMessenger: (NSObject<FlutterBinaryMessenger>*)  messenger codec: (NSObject<FlutterMessageCodec>*)  codec taskQueue: (NSObject<FlutterTaskQueue>*)  taskQueue

implementation

Definition at line 73 of file FlutterChannels.mm.

                            :(NSString*)name
             binaryMessenger:(NSObject<FlutterBinaryMessenger>*)messenger
                       codec:(NSObject<FlutterMessageCodec>*)codec
                   taskQueue:(NSObject<FlutterTaskQueue>*)taskQueue {
  self = [super init];
  NSAssert(self, @"Super init cannot be nil");
  _name = [name copy];
  _messenger = messenger;
  _codec = codec;
  _taskQueue = taskQueue;
  return self;
}

initWithName:binaryMessenger:codec:taskQueue: [2/2]

- (instancetype) initWithName:		(NSString *)	name
binaryMessenger:		(NSObject< FlutterBinaryMessenger > *)	messenger
codec:		(NSObject< FlutterMessageCodec > *)	codec
taskQueue:		(NSObject< FlutterTaskQueue > *_Nullable)	taskQueue

Initializes a FlutterBasicMessageChannel with the specified name, binary messenger, and message codec.

The channel name logically identifies the channel; identically named channels interfere with each other's communication.

The binary messenger is a facility for sending raw, binary messages to the Flutter side. This protocol is implemented by FlutterEngine and FlutterViewController.

Parameters

name	The channel name.
messenger	The binary messenger.
codec	The message codec.
taskQueue	The FlutterTaskQueue that executes the handler (see -[FlutterBinaryMessenger makeBackgroundTaskQueue]).

messageChannelWithName:binaryMessenger:

+ (instancetype) messageChannelWithName:		(NSString*)	name
binaryMessenger:		(NSObject<FlutterBinaryMessenger>*)	messenger

Creates a FlutterBasicMessageChannel with the specified name and binary messenger.

The channel name logically identifies the channel; identically named channels interfere with each other's communication.

The binary messenger is a facility for sending raw, binary messages to the Flutter side. This protocol is implemented by FlutterEngine and FlutterViewController.

The channel uses FlutterStandardMessageCodec to encode and decode messages.

Parameters

name	The channel name.
messenger	The binary messenger.

Definition at line 73 of file FlutterChannels.mm.

                                      :(NSString*)name
                       binaryMessenger:(NSObject<FlutterBinaryMessenger>*)messenger {
  NSObject<FlutterMessageCodec>* codec = [FlutterStandardMessageCodec sharedInstance];
  return [FlutterBasicMessageChannel messageChannelWithName:name
                                            binaryMessenger:messenger
                                                      codec:codec];
}

messageChannelWithName:binaryMessenger:codec:

+ (instancetype) messageChannelWithName:		(NSString*)	name
binaryMessenger:		(NSObject<FlutterBinaryMessenger>*)	messenger
codec:		(NSObject<FlutterMessageCodec>*)	codec

Creates a FlutterBasicMessageChannel with the specified name, binary messenger, and message codec.

The channel name logically identifies the channel; identically named channels interfere with each other's communication.

The binary messenger is a facility for sending raw, binary messages to the Flutter side. This protocol is implemented by FlutterEngine and FlutterViewController.

Parameters

name	The channel name.
messenger	The binary messenger.
codec	The message codec.

Definition at line 73 of file FlutterChannels.mm.

                                      :(NSString*)name
                       binaryMessenger:(NSObject<FlutterBinaryMessenger>*)messenger
                                 codec:(NSObject<FlutterMessageCodec>*)codec {
  return [[FlutterBasicMessageChannel alloc] initWithName:name
                                          binaryMessenger:messenger
                                                    codec:codec];
}

resizeChannelBuffer:

- (void) resizeChannelBuffer:

(NSInteger)

newSize

Adjusts the number of messages that will get buffered when sending messages to channels that aren't fully set up yet. For example, the engine isn't running yet or the channel's message handler isn't set up on the Dart side yet.

Parameters

newSize

The number of messages that will get buffered.

Definition at line 73 of file FlutterChannels.mm.

                           :(NSInteger)newSize {
  ResizeChannelBuffer(_messenger, _name, newSize);
}

resizeChannelWithName:binaryMessenger:size:

+ (void) resizeChannelWithName:		(NSString*)	name
binaryMessenger:		(NSObject<FlutterBinaryMessenger>*)	messenger
size:		(NSInteger)	newSize

Adjusts the number of messages that will get buffered when sending messages to channels that aren't fully set up yet. For example, the engine isn't running yet or the channel's message handler isn't set up on the Dart side yet.

Parameters

name	The channel name.
messenger	The binary messenger.
newSize	The number of messages that will get buffered.

Definition at line 73 of file FlutterChannels.mm.

                             :(NSString*)name
              binaryMessenger:(NSObject<FlutterBinaryMessenger>*)messenger
                         size:(NSInteger)newSize {
  ResizeChannelBuffer(messenger, name, newSize);
}

sendMessage: [1/2]

- (void) sendMessage:

(id _Nullable)

message

Sends the specified message to the Flutter side, ignoring any reply.

Parameters

message

The message. Must be supported by the codec of this channel.

Reimplemented in FakeMessageChannel.

sendMessage: [2/2]

- (void) sendMessage: (id)  message

implementation

Definition at line 73 of file FlutterChannels.mm.

                   :(id)message {
  [_messenger sendOnChannel:_name message:[_codec encode:message]];
}

sendMessage:reply: [1/2]

- (void) sendMessage:		(id _Nullable)	message
reply:		(FlutterReply _Nullable)	callback

Sends the specified message to the Flutter side, expecting an asynchronous reply.

Parameters

message	The message. Must be supported by the codec of this channel.
callback	A callback to be invoked with the message reply from Flutter.

Reimplemented in FakeMessageChannel.

sendMessage:reply: [2/2]

- (void) sendMessage: (id)  message reply: (FlutterReply)  callback

implementation

Definition at line 73 of file FlutterChannels.mm.

                   :(id)message reply:(FlutterReply)callback {
  FlutterBinaryReply reply = ^(NSData* data) {
    if (callback) {
      callback([_codec decode:data]);
    }
  };
  [_messenger sendOnChannel:_name message:[_codec encode:message] binaryReply:reply];
}

setMessageHandler: [1/2]

- (void) setMessageHandler:

(FlutterMessageHandler _Nullable)

handler

Registers a message handler with this channel.

Replaces any existing handler. Use a nil handler for unregistering the existing handler.

Parameters

handler

The message handler.

setMessageHandler: [2/2]

- (void) setMessageHandler: (FlutterMessageHandler)  handler

implementation

Definition at line 73 of file FlutterChannels.mm.

                         :(FlutterMessageHandler)handler {
  if (!handler) {
    if (_connection > 0) {
      [_messenger cleanUpConnection:_connection];
      _connection = 0;
    } else {
      [_messenger setMessageHandlerOnChannel:_name binaryMessageHandler:nil];
    }
    return;
  }
 
  // Grab reference to avoid retain on self.
  // `self` might be released before the block, so the block needs to retain the codec to
  // make sure it is not released with `self`
  NSObject<FlutterMessageCodec>* codec = _codec;
  FlutterBinaryMessageHandler messageHandler = ^(NSData* message, FlutterBinaryReply callback) {
    handler([codec decode:message], ^(id reply) {
      callback([codec encode:reply]);
    });
  };
  _connection = SetMessageHandler(_messenger, _name, messageHandler, _taskQueue);
}

setWarnsOnOverflow:

- (void) setWarnsOnOverflow:

(BOOL)

warns

Defines whether the channel should show warning messages when discarding messages due to overflow.

Parameters

warns

When false, the channel is expected to overflow and warning messages will not be shown.

Definition at line 73 of file FlutterChannels.mm.

                          :(BOOL)warns {
  SetWarnsOnOverflow(_messenger, _name, warns);
}

setWarnsOnOverflow:forChannelWithName:binaryMessenger:

+ (void) setWarnsOnOverflow:		(BOOL)	warns
forChannelWithName:		(NSString*)	name
binaryMessenger:		(NSObject<FlutterBinaryMessenger>*)	messenger

Defines whether the channel should show warning messages when discarding messages due to overflow.

Parameters

warns	When false, the channel is expected to overflow and warning messages will not be shown.
name	The channel name.
messenger	The binary messenger.

Definition at line 73 of file FlutterChannels.mm.

                          :(BOOL)warns
        forChannelWithName:(NSString*)name
           binaryMessenger:(NSObject<FlutterBinaryMessenger>*)messenger {
  SetWarnsOnOverflow(messenger, name, warns);
}

---

The documentation for this class was generated from the following files:

• shell/platform/darwin/common/framework/Headers/FlutterChannels.h
• shell/platform/darwin/common/framework/Source/FlutterChannels.mm