BACKGROUND:
I want to be able to send and receive UDP packets between my iOS app and a server. The server echoes back every incoming message to the client the app. The server is tested and confirmed working. I have a StartViewController which starting up two classes that implements GCDAsyncUdpSocketDelegate, one for sending and one for receiving. The "sending socket" is working, the server receives the messages.
PROBLEM:
The app never get the incoming message back after it been sent. Something with the listening socket setup is probably wrong since didReceiveData never get called.
Have I done this completely wrong?
Start:
class StartViewController: UIViewController {
var inSocket : InSocket!
var outSocket : OutSocket!
override func viewDidLoad() {
super.viewDidLoad()
inSocket = InSocket()
outSocket = OutSocket()
}
@IBAction func goButton(sender: UIButton) {
outSocket.send("This is a message!")
}
}
Receive:
class InSocket: NSObject, GCDAsyncUdpSocketDelegate {
let IP = "255.255.255.255"
let PORT:UInt16 = 5556
var socket:GCDAsyncUdpSocket!
override init(){
super.init()
setupConnection()
}
func setupConnection(){
var error : NSError?
socket = GCDAsyncUdpSocket(delegate: self, delegateQueue: dispatch_get_main_queue())
socket.bindToPort(PORT, error: &error)
socket.enableBroadcast(true, error: &error)
socket.joinMulticastGroup(IP, error: &error)
socket.beginReceiving(&error)
}
func udpSocket(sock: GCDAsyncUdpSocket!, didReceiveData data: NSData!, fromAddress address: NSData!, withFilterContext filterContext: AnyObject!) {
println("incoming message: \(data)");
}
}
Send:
class OutSocket: NSObject, GCDAsyncUdpSocketDelegate {
let IP = "90.112.76.180"
let PORT:UInt16 = 5556
var socket:GCDAsyncUdpSocket!
override init(){
super.init()
setupConnection()
}
func setupConnection(){
var error : NSError?
socket = GCDAsyncUdpSocket(delegate: self, delegateQueue: dispatch_get_main_queue())
socket.connectToHost(IP, onPort: PORT, error: &error)
}
func send(message:String){
let data = message.dataUsingEncoding(NSUTF8StringEncoding)
socket.sendData(data, withTimeout: 2, tag: 0)
}
func udpSocket(sock: GCDAsyncUdpSocket!, didConnectToAddress address: NSData!) {
println("didConnectToAddress");
}
func udpSocket(sock: GCDAsyncUdpSocket!, didNotConnect error: NSError!) {
println("didNotConnect \(error)")
}
func udpSocket(sock: GCDAsyncUdpSocket!, didSendDataWithTag tag: Int) {
println("didSendDataWithTag")
}
func udpSocket(sock: GCDAsyncUdpSocket!, didNotSendDataWithTag tag: Int, dueToError error: NSError!) {
println("didNotSendDataWithTag")
}
}
Edit: Added forgotten code line.
I finally got it to work with this socket setup:
func setupConnection(){
var error : NSError?
socket = GCDAsyncUdpSocket(delegate: self, delegateQueue: dispatch_get_main_queue())
socket.bindToPort(PORT, error: &error)
socket.connectToHost(SERVER_IP, onPort: PORT, error: &error)
socket.beginReceiving(&error)
send("ping")
}
func send(message:String){
let data = message.dataUsingEncoding(NSUTF8StringEncoding)
socket.sendData(data, withTimeout: 2, tag: 0)
}