I made a watchOS connectivity application and it works. Now I'm trying to make a dedicated classes for Connection at iPhone and Watch. For the iPhone connectivity class I have this (I also have other methods for transferring data but the problem is here):
import UIKit
import WatchConnectivity
class iPhoneConnectivity: UIViewController, WCSessionDelegate {
func session(_ session: WCSession, activationDidCompleteWith activationState: WCSessionActivationState, error: Error?) {
}
func sessionDidBecomeInactive(_ session: WCSession) {
}
func sessionDidDeactivate(_ session: WCSession) {
}
var session : WCSession!;
func getPrepared() {
if (WCSession.isSupported()) {
// check if the watch connectivity is suported on device
self.session = WCSession.default;
self.session.delegate = self;
self.session.activate();
} else {
print("Session is not supported")
}
}
}
The problem is that when I try to call this method in ViewController
connect.getPrepared();
The application quits unexpectedly.
I have a global variable
var connect: iPhoneConnectivity!;
Is that because I didn't initialize the connect variable? If that's the problem, how should I initialized it?
In original application, which works, I have this code of getPrepared() method in ViewController's method didLoad()
The issue is that connect is an implicitly unwrapped optional and you call a function on it without actually initializing it. Implicitly unwrapped optionals are still optionals and hence if you don't give them a value, they are nil by default. Hence when you try to access them without giving them a non-nil value first, you will get a runtime exception.
Define connect as a singleton and not as a global variable.
class iPhoneConnectivity: WCSessionDelegate {
static let sharedInstance = iPhoneConnectivity()
func session(_ session: WCSession, activationDidCompleteWith activationState: WCSessionActivationState, error: Error?) {}
func sessionDidBecomeInactive(_ session: WCSession) {}
func sessionDidDeactivate(_ session: WCSession) {}
var session : WCSession!;
func getPrepared() {
if (WCSession.isSupported()) {
// check if the watch connectivity is suported on device
self.session = WCSession.default;
self.session.delegate = self;
self.session.activate();
} else {
print("Session is not supported")
}
}
}
You can access it using iPhoneConnectivity.sharedInstance and call getPrepared() using iPhoneConnectivity.sharedInstance.getPrepared().