Sending and Receiving an Invitation with Multipeer Connectivity

Question

I know this question has been asked before, but I was just wondering why it isn't working in my particular case.

I am trying to send an invitation from multipeer connectivity from one view controller and receive it on another. My code for sending it is:

[self invitePeer:selectedPeerID toSession:self.mySession withContext:nil timeout:timeInterval ];

and method is just blank:

 - (void)invitePeer:(MCPeerID *)peerID toSession:(MCSession *)session withContext:(NSData *)context timeout:(NSTimeInterval)timeout 
 {

 }

My code for receiving and invitation is:

 - (void)advertiser:(MCNearbyServiceAdvertiser *)advertiser didReceiveInvitationFromPeer:(MCPeerID *)peerID withContext:(NSData *)context invitationHandler:(void(^)(BOOL accept, MCSession *session))invitationHandler 
 {

      // http://down.vcnc.co.kr/WWDC_2013/Video/708.pdf  -- wwdc tutorial, this part is towards the end (p119)

      self.arrayInvitationHandler = [NSArray arrayWithObject:[invitationHandler copy]];
      // ask the user
      UIAlertView *alertView = [[UIAlertView alloc]
                          initWithTitle:peerID.displayName
                          message:@"Would like to create a session with you"
                          delegate:self
                          cancelButtonTitle:@"Decline" otherButtonTitles:@"Accept", nil];
      [alertView show];


  }

 - (void) alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex 
 {
      // retrieve the invitationHandler and  check whether the user accepted or declined the invitation...

      BOOL accept = (buttonIndex != alertView.cancelButtonIndex) ? YES : NO;

      // respond
      if(accept) {
              void (^invitationHandler)(BOOL, MCSession *) = [self.arrayInvitationHandler objectAtIndex:0];
    invitationHandler(accept, self.mySession);
          }
          else 
          {
              NSLog(@"Session disallowed");
          }
  }

I have all the delegate methods correctly set up as well as the same service types and that. But when i try to initiate the session, the tableviewcell which i click on just remains highlighted...

I'm thinking I have to put something in the invitePeer toSession method but I'm not sure...

I copied this directly from Apple's wwdc talk on Multipeer Connectivity referenced in my code... As you can see it is my own implementation of the code and I am not using an advertiser assistant or the mcbrowserviewcontroller.

Does anyone have any suggestions as to how I can get this to work??

Answer 1

The invitePeer: toSession: withContext: timeOut: method is implemented by MCNearbyServiceBrowser so you should be calling that on the browser not on self.

[browser invitePeer:selectedPeerID toSession:self.mySession withContext:nil timeout:timeInterval ];

However, if you're trying to troubleshoot accepting invitations I'd skip the alert view for now and just accept right away in the didReceiveInvitation: callback of the advertiser delegate.

Edit

I'd originally stated that the delegate callbacks from Multipeer Connectivity classes came in on private queues but as @Juguang pointed out this is only the case for MCSessionDelegate callbacks.

Answer 2

For anyone interested, I created MCSessionP2P, a demo app that illustrates the ad-hoc networking features of MCSession. SessionController conforms to MCSessionDelegate, MCNearbyServiceBrowserDelegate and MCNearbyServiceAdvertiserDelegate and acts as the datasource for a UITableView. The app advertises itself via Wi-Fi or Bluetooth and programmatically connects to available peers, establishing a peer-to-peer network.