Lately, I am working on a project is related to ?Watch/iPhone communication again. But my code works sometimes and doesn’t work sometimes which is kind of weird to me because I think the code should either work or not. It cannot be 50/50. Therefore, I have no idea what goes wrong.
setup WCSession on iPhone:
class WatchCommunicationController: NSObject, WCSessionDelegate {
var session : WCSession?
override init(){
// super class init
super.init()
// if WCSession is supported
if WCSession.isSupported() { // it is supported
// get default session
session = WCSession.defaultSession()
// set delegate
session!.delegate = self
// activate session
session!.activateSession()
} else {
print("iPhone does not support WCSession")
}
}
... ...
}
similar WCSession setup on ?Watch:
class PhoneCommunicationController: NSObject, WCSessionDelegate {
var session : WCSession?
override init(){
// super class init
super.init()
// if WCSession is supported
if WCSession.isSupported() { // it is supported
// get default session
session = WCSession.defaultSession()
// set delegate
session!.delegate = self
// activate session
session!.activateSession()
} else {
print("?Watch does not support WCSession")
}
}
... ...
}
send out message on ?Watch:
func sendGesture(gesture : GKGesture){
// if WCSession is reachable
if session!.reachable { // it is reachable
// create the interactive message with gesture
let message : [String : AnyObject]
message = [
"Type":"Gesture",
"Content":gesture.rawValue
]
// send message
session!.sendMessage(message, replyHandler: nil, errorHandler: nil)
print("?Watch send gesture (gesture)")
} else{ // it is not reachable
print("WCSession is not reachable")
}
}
related enum:
enum GKGesture: Int {
case Push = 0, Left, Right, Up, Down
}
receive message on iPhone:
func session(session: WCSession, didReceiveMessage message: [String : AnyObject]) {
//retrieve info
let type = message["Type"] as! String
let content = message["Content"]
switch type {
case "Gesture":
handleGesture(GKGesture(rawValue: content as! Int)!)
default:
print("Received message (message) is invalid with type of (type)")
}
}
func handleGesture(gesture : GKGesture){
print("iPhone receives gesture (gesture)")
var notificationName = ""
switch gesture {
case .Up:
notificationName = "GestureUp"
case .Down:
notificationName = "GestureDown"
case .Left:
notificationName = "GestureLeft"
case .Right:
notificationName = "GestureRight"
case .Push:
notificationName = "GesturePush"
}
NSNotificationCenter.defaultCenter().postNotificationName(notificationName, object: nil)
}
somehow I can’t debug my ?Watch app on Xcode, the debug session just won’t attach. I don’t know why. Therefore, I debug one-sided with just the iPhone.
sometimes I got "receives gesture” print out, and sometimes not. And the same for getting the notification.
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