iOS Components and Frameworks: Understanding the Advanced Features of the iOS SDK

Receiving Data

Sending data is pointless if the receiving peer is not set up to handle that data. The first thing that needs to be done when preparing your app to receive data is letting the GKSession know which class will handle the incoming messages by setting the dataReceiveHandler. An example is shown in the following code snippet:

Click here to view code image

[self.currentSession setDataReceiveHandler:self withContext:nil];

A data handler needs to be set for each session and is session-specific. You can define a context as part of the setDataReceiveHandler: and this context will be passed along as part of any incoming data calls.

Every time your session receives data, your data handler will call receiveData:fromPeer:inSession:context