kmmraj/setMethodCallHandler.kt

## setMethodCallHandler.kt
channel.setMethodCallHandler { methodCall, result ->
            when (methodCall.method){
                "handleMessageBack" -> {
                    this.onBackPressed()
                }
                else -> {  // Do something else
                }
            }
        }
	channel.setMethodCallHandler { methodCall, result ->
	when (methodCall.method){
	"handleMessageBack" -> {
	this.onBackPressed()
	}
	else -> { // Do something else
	}
	}
	}