Error with FindViewById used in a Broadcast receiver with Xamarin.Android

Question

I have an activity with a BroadcastReceiver in it as shown in this code:

public  class MyActivity : Activity
    {
       protected override void OnCreate(Bundle savedInstanceState)
    {
        base.OnCreate(savedInstanceState);

        // Create your application here
        SetContentView(Resource.Layout.activity_myActivity);

        int method = Intent.GetIntExtra(KEY_MYACTIVITY_METHOD, METHOD_MYACTIVITY);

        mAlgo= new algo(this);            
        intent = new Intent(this, typeof( BroadcastService) ); //*****
    }

     [BroadcastReceiver(Enabled = true)]
    [IntentFilter(new[] { Android.Content.Intent.ActionBootCompleted })]
    private  class broadcastReceiver : BroadcastReceiver
    {
        public override void OnReceive(Context context, Intent intent)
        {
            updateUI(intent);
        }
        private   void updateUI(Intent intent)
        {
            float mx = mAlgo.getmX();

            TextView startx =FindViewById<TextView>(Resource.Id.startx);  //ERROR


        }

    }
}

I have the error with FindViewById which tell that An object reference is required for the property , method, or the non-static field Activity.FindViewById(int)'. Can you see what is going wrong? thank you

Answer 1

You can't call FindViewById from a nested class. You could:

1) Hold a reference to the activity object inside the nested broadcastReceiver class:

public class MyActivity : Activity {

    ...

    private class broadCastReceiver : BroadcastReceiver {
        private MyActivity act;

        public broadCastReceiver (MyActivity act) {
            this.act = act;
        }

        private void updateUI (Intent intent) {
            TextView startx = act.FindViewById<TextView> (Resource.Id.startx);
        }
    }
}

2) Or hold a reference to the TextView in the activity and pass it to the broadcast receiver similarly like in the 1st example.