Watch Connectivity:didReceiveMessage未调用

Question

我正在使用WatchConnectivity框架从我的应用程序接收一个字符串.这是我如何从应用程序发送Obj-C中的字符串:

-(void) viewDidLoad {

    //WATCHKIT
    WCSession* session = [WCSession defaultSession];
    session.delegate = self;
    [session activateSession];

    [self sendInfoToWatch];
}

-(void) sendInfoToWatch {

    WCSession* session = [WCSession defaultSession];
    session.delegate = self;
    [session activateSession];

    [session sendMessage:@{@"a":@"hello"} replyHandler:^(NSDictionary<NSString *,id> * _Nonnull replyMessage) {

    } errorHandler:^(NSError * _Nonnull error) {

    }];
}

我的Watch应用程序在Swift中.这是我检索消息的方式:

注意: "支持wc会话"工作并记录到控制台

override func willActivate() {
    if(WCSession.isSupported()){
        NSLog("wc session is supported")
        self.session = WCSession.defaultSession()
        self.session.delegate = self
        self.session.activateSession()
    }

    super.willActivate()
}

永远不会调用以下函数,NSLog的任何一个都不会显示,因此QRCodeTitleLabel不会更新其文本.

func session(session: WCSession, didReceiveMessage message: [String : AnyObject]) {
    //recieving message from iphone

    QRCodeTitleLabel.setText(message["a"]! as? String)

    NSLog("This was called")
    NSLog((message["a"]! as? String)!)

}

有谁知道为什么不调用这个方法？

此外,我已导入WatchConnectivity并在我的类名后包含WCSessionDelegate.

编辑:

我用replyHandler添加了函数,但是这个方法仍然没有被调用:

func session(session: WCSession, didReceiveMessage message: [String : AnyObject], replyHandler: ([String : AnyObject]) -> Void) {
    QRCodeTitleLabel.setText(message["a"]! as? String)

    NSLog("This was called")
    NSLog((message["a"]! as? String)!)
}

Answer 1

WCSession中有2个session:didReceiveMessage方法.您应该在Apple Watch一侧使用replyHandler实现一个.

此外,Apple Watch屏幕是否开启？来自iPhone的SendMessage仅在Apple Watch应用程序处于活动状态且屏幕打开时才有效.另一方面,即使iPhone应用程序未启动,从Apple Watch到iPhone的SendMessage也能正常工作.

如果要在使用Watch应用程序时请求数据,可以切换Watch App以调用sendMessage方法.iPhone应用程序将使用其replyHandler将您需要的数据发送回手表.如果这样做,您需要将iPhone应用程序中的WCSession初始化代码移动到应用程序中:didFinishLaunchingWithOptions方法(因为如果在后台启动,您的视图控制器将不会被初始化).

// ***On the watch***
// ExtensionDelegate
func applicationDidFinishLaunching() { 
    self.session = WCSession.defaultSession();       
    self.session.delegate = self
    self.session.activateSession()
}

// Where you want to get the data from the iPhone
self.session.sendMessage(["retrieveData":[:]], replyHandler: { (result) -> Void in
    // TODO: Handle your data from the iPhone
}, errorHandler: { (error) -> Void in
    // TODO: Handle error - iPhone many not be reachable
})

// ***On the iPhone***
// AppDelegate
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.session = [WCSession defaultSession];
    self.session.delegate = self;
    [self.session activateSession];
}

- (void)session:(WCSession *)session didReceiveMessage:(nonnull NSDictionary<NSString *,id> *)message replyHandler:(nonnull void (^)(NSDictionary<NSString *,id> * _Nonnull))replyHandler
{
    if ([message objectForKey:@"retrieveData"])
    {
        replyHandler(@{@"a":@"hello"});
    }
}