如何为多个NSProgress使用observeValueForKeyPath？

Question

I have implemented file sending functionality for connected peers from loop using multiplier connectivity. That code as follows.

for connectedPeer in self.connectedPeers {
       let sendingProgress = self.session.sendResourceAtURL(newPhotoUrl!, withName: "Image1", toPeer: connectedPeer, withCompletionHandler: { (error) in
            if error != nil {
                print("sending failed \(error!.localizedDescription) - \(connectedPeer.displayName)")
            }
     })
      sendingProgress.addObserver(self, forKeyPath: "fractionCompleted", options: .New, context: nil)
    }

It's sending properly. I want to show each peer's sending progress on sender device. I can get progress from observeValueForKeyPath method. But how can I identify each sending progress individually from observeValueForKeyPath method.

Answer 1

You can use the parameter context for identifying the progress. Instead of nil you should give the url or the connected peer.