FlutterJSONMethodCodec Class Reference

#include <FlutterCodecs.h>

Inheritance diagram for FlutterJSONMethodCodec:

Instance Methods
(NSData *)	- encodeMethodCall: [implementation]
(NSData *)	- encodeSuccessEnvelope: [implementation]
(NSData *)	- encodeErrorEnvelope: [implementation]
(FlutterMethodCall *)	- decodeMethodCall: [implementation]
(id)	- decodeEnvelope: [implementation]
(id)	- wrapNil: [implementation]
(id)	- unwrapNil: [implementation]

Class Methods
(instancetype)	+ sharedInstance [implementation]

Detailed Description

An arbitrarily large integer value, used with FlutterStandardMessageCodec and FlutterStandardMethodCodec. A codec for method calls and enveloped results.

Method calls are encoded as binary messages with enough structure that the codec can extract a method name NSString and an arguments NSObject, possibly nil. These data items are used to populate a FlutterMethodCall.

Result envelopes are encoded as binary messages with enough structure that the codec can determine whether the result was successful or an error. In the former case, the codec can extract the result NSObject, possibly nil. In the latter case, the codec can extract an error code NSString, a human-readable NSString error message (possibly nil), and a custom error details NSObject, possibly nil. These data items are used to populate a FlutterError. Provides access to a shared instance this codec.

Returns

The shared instance. Encodes the specified method call into binary.

Parameters

methodCall

The method call. The arguments value must be supported by this codec.

Returns

The binary encoding. Decodes the specified method call from binary.

Parameters

methodCall

The method call to decode.

Returns

The decoded method call. Encodes the specified successful result into binary.

Parameters

result

The result. Must be a value supported by this codec.

Returns

The binary encoding. Encodes the specified error result into binary.

Parameters

error

The error object. The error details value must be supported by this codec.

Returns

The binary encoding. Deccodes the specified result envelope from binary.

Parameters

envelope

The error object.

Returns

The result value, if the envelope represented a successful result, or a FlutterError instance, if not. A FlutterMethodCodec using UTF-8 encoded JSON method calls and result envelopes.

This codec is guaranteed to be compatible with the corresponding JSONMethodCodec on the Dart side. These parts of the Flutter SDK are evolved synchronously.

Values supported as methods arguments and result payloads are those supported as top-level or leaf values by FlutterJSONMessageCodec.

Definition at line 455 of file FlutterCodecs.h.

Method Documentation

decodeEnvelope:

- (id) decodeEnvelope: (NSData*)  envelope

implementation

Definition at line 9 of file FlutterCodecs.mm.

                    :(NSData*)envelope {
  NSArray* array = [[FlutterJSONMessageCodec sharedInstance] decode:envelope];
  if (array.count == 1) {
    return [self unwrapNil:array[0]];
  }
  NSAssert(array.count == 3, @"Invalid JSON envelope");
  id code = array[0];
  id message = [self unwrapNil:array[1]];
  id details = [self unwrapNil:array[2]];
  NSAssert([code isKindOfClass:[NSString class]], @"Invalid JSON envelope");
  NSAssert(message == nil || [message isKindOfClass:[NSString class]], @"Invalid JSON envelope");
  return [FlutterError errorWithCode:code message:message details:details];
}

decodeMethodCall:

- (FlutterMethodCall *) decodeMethodCall: (NSData*)  message

implementation

Definition at line 9 of file FlutterCodecs.mm.

                                      :(NSData*)message {
  NSDictionary* dictionary = [[FlutterJSONMessageCodec sharedInstance] decode:message];
  id method = dictionary[@"method"];
  id arguments = [self unwrapNil:dictionary[@"args"]];
  NSAssert([method isKindOfClass:[NSString class]], @"Invalid JSON method call");
  return [FlutterMethodCall methodCallWithMethodName:method arguments:arguments];
}

encodeErrorEnvelope:

- (NSData *) encodeErrorEnvelope: (FlutterError*)  error

implementation

Definition at line 9 of file FlutterCodecs.mm.

                              :(FlutterError*)error {
  return [[FlutterJSONMessageCodec sharedInstance] encode:@[
    error.code,
    [self wrapNil:error.message],
    [self wrapNil:error.details],
  ]];
}

encodeMethodCall:

- (NSData *) encodeMethodCall: (FlutterMethodCall*)  call

implementation

Definition at line 9 of file FlutterCodecs.mm.

                           :(FlutterMethodCall*)call {
  return [[FlutterJSONMessageCodec sharedInstance] encode:@{
    @"method" : call.method,
    @"args" : [self wrapNil:call.arguments],
  }];
}

encodeSuccessEnvelope:

- (NSData *) encodeSuccessEnvelope: (id)  result

implementation

Definition at line 9 of file FlutterCodecs.mm.

                                :(id)result {
  return [[FlutterJSONMessageCodec sharedInstance] encode:@[ [self wrapNil:result] ]];
}

sharedInstance

+ (instancetype) sharedInstance

implementation

Definition at line 9 of file FlutterCodecs.mm.

                               {
  static id _sharedInstance = nil;
  if (!_sharedInstance) {
    _sharedInstance = [[FlutterJSONMethodCodec alloc] init];
  }
  return _sharedInstance;
}

unwrapNil:

- (id) unwrapNil: (id)  value

implementation

Definition at line 9 of file FlutterCodecs.mm.

               :(id)value {
  return value == [NSNull null] ? nil : value;
}

wrapNil:

- (id) wrapNil: (id)  value

implementation

Definition at line 9 of file FlutterCodecs.mm.

             :(id)value {
  return value == nil ? [NSNull null] : value;
}

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

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