我目前有两个设备通过多对等连接框架相互连接。当连接时，每个设备将立即相互发送一组nsdata，在第一种情况下，数据将包含声音和图像。这似乎工作正常，用户都收到相关数据。
用户现在可以从视图中相互选择并发送另一位数据。但是，我发现如果主机（发送邀请的客户端）尝试发送更多数据，则控制台中会显示以下错误。
Peers (
PeerName
) not connected
但是如果客户端（被邀请者）发送数据，它将按预期在主机上到达。特别有趣的是我在NSV中有这样的事实：
-(void)peerDidChangeStateWithNotification:(NSNotification *)notification
发生断开连接时触发的方法，没有断开连接且设备彼此连接。我的代码如下，是否有人知道为什么会这样？
#pragma mark Send Buzz Notification
#pragma mark -
-(void)sendBuzzNotification{
// create the user (remove the image to lower size)
LocalUserClass *withoutImage = [[LocalUserClass alloc]initWithName:[[[GlobalData sharedGlobalData]localUser]personName] personImage:nil personSound:[[[GlobalData sharedGlobalData]localUser]personSound] personPeerId:nil];
// send the users sound and name to the other peer/s
NSData *dataToSend = [NSKeyedArchiver archivedDataWithRootObject:withoutImage];
NSError *error;
// skip if no users are selcted
if ([selectedUsers count] == 0) {
return;
}
else{
// create the array of peer Ids from selected users
NSMutableArray *tempArray = [[NSMutableArray alloc]init];
for (LocalUserClass *object in selectedUsers) {
// add the peer id
MCPeerID *theId = object.personPeerId;
[tempArray addObject:theId];
}
NSArray *theUsers = [[NSArray alloc]init];
theUsers = tempArray;
// send the data
[appDelegate.mcManager.session sendData:dataToSend
toPeers:theUsers
withMode:MCSessionSendDataReliable
error:&error];
if (error) {
NSLog(@"%@", [error localizedDescription]);
}
// vibrate the device to show its been sent
AudioServicesPlaySystemSound(kSystemSoundID_Vibrate);
}
}
#pragma mark Peer Connected State Checker
#pragma mark -
-(void)peerDidChangeStateWithNotification:(NSNotification *)notification{
MCPeerID *peerID = [[notification userInfo] objectForKey:@"peerID"];
//NSLog(@"%@",peerID.displayName);
MCSessionState state = [[[notification userInfo] objectForKey:@"state"] intValue];
LocalUserClass *theUser = [[LocalUserClass alloc]initWithName:peerID.displayName personImage:nil personSound:nil personPeerId:peerID];
//NSLog(@"the user name is: %@ the user sound is: %@ the user peer id is %@",theUser.personName,theUser.personSound,theUser.personPeerId);
if (state != MCSessionStateConnecting) {
if (state == MCSessionStateConnected) {
// add the user
[connectedUsers addObject:theUser];
// send the users details to the newly connected peer (profile pic and sound)
[self sendUserDetailsToPeer:peerID];
}
else if (state == MCSessionStateNotConnected){
// do we have connections
if ([connectedUsers count] > 0) {
// get the user to remove
NSInteger thePeerIndex = 0;
NSInteger thePeerIndexSelectedUsers = 0;
for (LocalUserClass *object in connectedUsers) {
if (object.personPeerId == theUser.personPeerId) {
thePeerIndex = [connectedUsers indexOfObject:object];
[connectedUsers removeObjectAtIndex:thePeerIndex];
}
}
for (LocalUserClass *user in selectedUsers) {
if (user.personPeerId == theUser.personPeerId) {
thePeerIndexSelectedUsers = [selectedUsers indexOfObject:user];
[selectedUsers removeObjectAtIndex:thePeerIndexSelectedUsers];
}
}
}
}
}
// push to main queue for speedy response
dispatch_async(dispatch_get_main_queue(), ^(void) {
// create user playback devices
[playbackManager createUserAudioPlayers:connectedUsers withSound:nil];
[collView reloadData];
[self populateUserBox];
BOOL peersExist = ([[appDelegate.mcManager.session connectedPeers] count] == 0);
//NSLog(@"PEER COUNT IS %lu",(unsigned long)[[appDelegate.mcManager.session connectedPeers] count]);
[disconnectButton setEnabled:!peersExist];
if ([disconnectButton isEnabled]) {
[disconnectButton setBackgroundColor:[UIColor colorWithRed:(51/255.0) green:(202/255.0) blue:(168/255.0) alpha:1.0]];
}
else{
[disconnectButton setBackgroundColor:[UIColor colorWithRed:(107/255.0) green:(107/255.0) blue:(107/255.0) alpha:1.0]];
}
});
}
#pragma mark Peer Received Data
#pragma mark -
-(void)didReceiveDataWithNotification:(NSNotification *)notification{
NSData *receivedData = [[notification userInfo] objectForKey:@"data"];
receivedUser = [NSKeyedUnarchiver unarchiveObjectWithData:receivedData];
CGImageRef cgref = [receivedUser.personImage CGImage];
CIImage *cim = [receivedUser.personImage CIImage];
// are we getting a whole user or just the user sound and name (check for no image)
if (cim == nil && cgref == NULL)
{
// recieve the data (TODO probably needs to be run in the background)
[self performSelectorOnMainThread:@selector(recieveBuzzNotification) withObject:nil waitUntilDone:YES];
}
else{
// recieve the data (TODO probably needs to be run in the background)
[self performSelectorOnMainThread:@selector(receivedUserProfile) withObject:nil waitUntilDone:YES];
}
}
更新：在初始数据传输后，主机似乎失去了与客户端的连接：
[self sendUserDetailsToPeer:peerID];
然而，断开状态不会触发任何内容，客户端仍然可以向主机发送数据。通过注销连接的会话可以看到这一点：
session.connectedPeers
编辑：视图控制器中的附加代码：
#pragma mark Create Session
#pragma mark -
-(void)setupSession{
// create session and peer with details from the user
[appDelegate.mcManager setupPeerAndSessionWithDisplayName:[[[GlobalData sharedGlobalData]localUser]personName]];
[appDelegate.mcManager advertiseSelf:visibleSwitch.isOn];
appDelegate.mcManager.browser.delegate = self;
// set global user peerId
[[[GlobalData sharedGlobalData]localUser]setPersonPeerId:appDelegate.mcManager.peerIDGlobal];
// setup notification to track the user info of connected peers
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(peerDidChangeStateWithNotification:)
name:@"MCDidChangeStateNotification"
object:nil];
// notifcation to track recieved data
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(didReceiveDataWithNotification:)
name:@"MCDidReceiveDataNotification"
object:nil];
}
和MCManager：
-(id)init{
self = [super init];
if (self) {
peerIDGlobal = nil;
session = nil;
browser = nil;
advertiser = nil;
}
return self;
}
//----CUSTOM---------------------------------------------------------------------------------------------------------------//
//-------------------------------------------------------------------------------------------------------------------------//
//----PUBLIC---------------------------------------------------------------------------------------------------------------//
#pragma mark Setup Peer and Session
#pragma mark -
-(void)setupPeerAndSessionWithDisplayName:(NSString *)displayName{
peerIDGlobal = [[MCPeerID alloc] initWithDisplayName:[[[GlobalData sharedGlobalData]localUser]personName]];
session = [[MCSession alloc] initWithPeer:peerIDGlobal];
session.delegate = self;
}
#pragma mark Setup Browser
#pragma mark -
-(void)setupMCBrowser{
browser = [[MCBrowserViewController alloc] initWithServiceType:@"chat-files" session:session];
}
#pragma mark Setup Advertiser
#pragma mark -
-(void)advertiseSelf:(BOOL)shouldAdvertise{
if (shouldAdvertise) {
advertiser = [[MCAdvertiserAssistant alloc] initWithServiceType:@"chat-files"
discoveryInfo:nil
session:session];
[advertiser start];
}
else{
[advertiser stop];
advertiser = nil;
}
}
//----DELEGATES------------------------------------------------------------------------------------------------------------//
//-------------------------------------------------------------------------------------------------------------------------//
#pragma mark Session delegate
#pragma mark -
-(void)session:(MCSession *)session peer:(MCPeerID *)peerID didChangeState:(MCSessionState)state{
// create the dict with connected user info
NSDictionary *dict = @{@"peerID": peerID,
@"state" : [NSNumber numberWithInt:state]
};
// post the notification for tracking
[[NSNotificationCenter defaultCenter] postNotificationName:@"MCDidChangeStateNotification"
object:nil
userInfo:dict];
}
-(void)session:(MCSession *)session didReceiveData:(NSData *)data fromPeer:(MCPeerID *)peerID{
NSDictionary *dict = @{@"data": data,
@"peerID": peerID
};
[[NSNotificationCenter defaultCenter] postNotificationName:@"MCDidReceiveDataNotification"
object:nil
userInfo:dict];
}
答案 0 :(得分：3)
谢谢Chris，这看起来是个问题，我根据这里的一些样板代码重写了代码： https://github.com/shrtlist/MCSessionP2P
现在该应用程序自动连接到没有浏览器的用户，这是一个很好的解决方案，我强烈建议有问题的人看看代码。
答案 1 :(得分：0)
当两台设备同时浏览/通告和发送/接受邀请时，Multipeer Connectivity存在已知问题。
Apple在WWDC 14期间推荐的解决方案是我在此发布的解决方案：Reconnecting to disconnected peers，它使用确定性方法来决定一对中的哪个同伴接受其他邀请。
MCBrowserViewController和MCAdvertiserAssistant似乎只能在一个同行正在浏览其他广告的应用中可靠地使用。
答案 2 :(得分：-1)
当设备同时进行广告和浏览时，我遇到了类似的问题。我在Apple WWDC视频中使用了这种方法（我相信），以确保没有重复的连接;
func browser(browser: MCNearbyServiceBrowser!, foundPeer peerID: MCPeerID!, withDiscoveryInfo info: [NSObject : AnyObject]!) {
if (self.myPeerID.hash > peerID.hash){
println("foundPeer:\(peerID.description) -> invitePeer")
mpBrowser.invitePeer(peerID, toSession: self.mpSession, withContext: nil, timeout: peerInviteTimeout)
}else{
println("foundPeer: \(peerID.description) hash is higher->defer invite")
}
}