protected override void OnTerminate()
{
base.OnTerminate();
MessagingCenter.Unsubscribe <Page, AlertArguments>(this, "Xamarin.SendAlert");
MessagingCenter.Unsubscribe <Page, bool>(this, "Xamarin.BusySet");
MessagingCenter.Unsubscribe <Page, ActionSheetArguments>(this, "Xamarin.ShowActionSheet");
if (_platform != null)
{
_platform.Dispose();
}
}