React Native Module 中的 EADemo 从不接收委托方法 handleEvent NSStreamEventOpenCompleted？

Question

我预计我有一个react native bridge module、线程、委托或生命周期问题，我不明白这会阻止接收委托方法调用。

我需要更改 NSStream scheduleInRunLoop 方法吗？

我正在尝试实现一个react native iOS bridge module 来连接基于Apple's EADemo example 的蓝牙“经典”（不是BLE）External Accessory。 EADemo 可以独立运行。

当我从 react native bridge 方法中调用EADSessionController openSession 时，handleEvent 方法永远不会被调用？

我希望 handleEvent 会收到 inputStream 和 outputStream 的 NSStreamEventOpenCompleted 事件。但是接收到零个事件。

文件：index.js

'use strict';
var RNBluetooth = require('react-native').NativeModules.RNBluetooth;
var Bluetooth = {
  connectTo(accessory, result) {
    RNBluetooth.connectTo(accessory, result);
  },
  };
  module.exports = Bluetooth;

文件：RNBluetooth.m

// open the external accesssory session from javascript
RCT_EXPORT_METHOD(connectTo:(NSDictionary *)accessoryProperties
                  callback:(RCTResponseSenderBlock)callback)
{
    // findAccessory returns the EAAccessory matching the accessoryProperties 
    EAAccessory * accessory = [self findAccessory:accessoryProperties];
    if(nil != accessory) {
        NSLog(@"Connect to:  {%@}", accessoryProperties[@"name"]);
        NSLog(@"name: {%@}", accessory.name);
        NSLog(@"serialNumber: {%@}", accessory.serialNumber);
        NSLog(@"connectionID: {%d}", (int)accessory.connectionID);
    }

    // Singleton
    EADSessionController * eaSessionController = [EADSessionController sharedController];
    [eaSessionController setupControllerForAccessory:accessory
                                   withProtocolString:accessoryProperties[@"protocolStrings"]];
    [eaSessionController openSession];

    NSString *dummyResponseString = @"openSession";
    callback(@[dummyResponseString]);
}

文件：EADSessionController.m

#import "EADSessionController.h"

NSString *EADSessionDataReceivedNotification = @"EADSessionDataReceivedNotification";

@implementation EADSessionController

@synthesize accessory = _accessory;
@synthesize protocolString = _protocolString;

#pragma mark Internal

#pragma mark Public Methods
+ (EADSessionController *)sharedController
{
    static EADSessionController *sessionController = nil;
    if (sessionController == nil) {
        sessionController = [[EADSessionController alloc] init];
    }
    return sessionController;
}

- (void)dealloc
{
    [self closeSession];
    [self setupControllerForAccessory:nil withProtocolString:nil];
    [super dealloc];
}

// initialize the accessory with the protocolString
- (void)setupControllerForAccessory:(EAAccessory *)accessory withProtocolString:(NSString *)protocolString
{
    [_accessory release];
    _accessory = [accessory retain];
    [_protocolString release];
    _protocolString = [protocolString copy];
}

// open a session with the accessory and set up the input and output stream on the default run loop
- (BOOL)openSession
{
    [_accessory setDelegate:self];
    _session = [[EASession alloc] initWithAccessory:_accessory forProtocol:_protocolString];
    if (_session)
    {
        [[_session inputStream] setDelegate:self];
        [[_session inputStream] scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
        [[_session inputStream] open];

        [[_session outputStream] setDelegate:self];
        [[_session outputStream] scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
        [[_session outputStream] open];
    }
    else
    {
        NSLog(@"creating session failed");
    }
    return (_session != nil);
}

// close the session with the accessory.
- (void)closeSession
{
    [[_session inputStream] close];
    [[_session inputStream] removeFromRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
    [[_session inputStream] setDelegate:nil];
    [[_session outputStream] close];
    [[_session outputStream] removeFromRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
    [[_session outputStream] setDelegate:nil];
    [_session release];
    _session = nil;
    [_writeData release];
    _writeData = nil;
    [_readData release];
    _readData = nil;
}

#pragma mark EAAccessoryDelegate
- (void)accessoryDidDisconnect:(EAAccessory *)accessory
{
    // do something ...
}

#pragma mark NSStreamDelegateEventExtensions

// handleEvent never gets called when session opened from react native bridge?
//
// asynchronous NSStream handleEvent method
- (void)stream:(NSStream *)aStream handleEvent:(NSStreamEvent)eventCode
{
    switch (eventCode) {
        case NSStreamEventNone:
            break;
        case NSStreamEventOpenCompleted:
            break;
        case NSStreamEventHasBytesAvailable:
            [self _readData];
            break;
        case NSStreamEventHasSpaceAvailable:
            [self _writeData];
            break;
        case NSStreamEventErrorOccurred:
            break;
        case NSStreamEventEndEncountered:
            break;
        default:
            break;
    }
}
@end

非常感谢任何提示或建议。

Answer 1

解决了。

将此添加到 RNBluetooth.m

// This seems to get NSStream handleEvents and the write command
// running on the same thread with no contention problems 
// writing to and reading from the write buffer
- (dispatch_queue_t)methodQueue
{
    return dispatch_get_main_queue();
}

参见Native Modules下的线程部分

现在可以从反应原生桥模块调用来自the EADemo example 的EADSessionController.m 没有问题。