Share data between Watch app and iOS app in watchOS2

Question

I send a dictionary to an iOS app using:

- (void)sendMessage:(NSDictionary<NSString *, id> *)message 
  replyHandler:(nullable void (^)(NSDictionary<NSString *, id> *replyMessage))replyHandler 
  errorHandler:(nullable void (^)(NSError *error))errorHandler;

but I'm getting an error with this. I want to know how our parent app handle this request in watchOS2.

In watchOS1, I used openParentApplication to get data from the parent app, and Appdelegate had a handleWatchKitExtensionRequest to handle that request. How do we handle this in watchOS2?

My Interface Controller:

- (void)awakeWithContext:(id)context 
{
   [super awakeWithContext:context];
   if([WCSession isSupported])
   {
     self.watchSession = [WCSession defaultSession];
     self.watchSession.delegate = self;
     [self.watchSession activateSession];
   }
   [self sendRequestWithActionType:@"InitialView"];
}

-(void)sendRequestWithActionType:(NSString *)action
{
    NSDictionary *requst = @{@"request":action};
    [[WCSession defaultSession] sendMessage:requst
                           replyHandler:^(NSDictionary *replyHandler) {
                               [self setTextForLabelWithData:[replyHandler valueForKey:@"response"]];
                           }
                           errorHandler:^(NSError *error) {
                               NSLog(@"");
                           }
 ];
}

Answer 1

Here is an example of using sendMessage with a reply:

Sending side:

-(void)sendRequestWithActionType:(NSString *)action {
    NSDictionary *request = @{@"request":action};
    [[WCSession defaultSession] sendMessage:request
                       replyHandler:^(NSDictionary *replyHandler) {
                           [self setTextForLabelWithData:[replyHandler valueForKey:@"response"]];
                       }
                       errorHandler:^(NSError *error) {
                           NSLog(@"");
                       }];
}

Receiving side:

- (void)session:(nonnull WCSession *)session didReceiveMessage:(NSDictionary<NSString *,id> *)message replyHandler:(void(^)(NSDictionary<NSString *,id> *))replyHandler { 
    NSString *action = message[@"request"];
    NSString *actionPerformed;
    if ([action isEqual:@"foo"]) {
        // do "foo" stuff
        actionPerformed = @"foo done";
    } else if ([action isEqual:@"bar"]) {
        // do "bar" stuff
        actionPerformed = @"bar done";
    }
    replyHandler(@{@"actionPerformed":actionPerformed});
}