Question

— This may be a non-issue — I am unable to reproduce this now w/ the device after fixing it and trying to revert back.

So I am a little confused, but here is some code. I changed up the code to simplify it some, so I may have a typo, but this is the ‘gist’ of what I am seeing. But basically on some devices example 1 won’t launch a dialog, while option 2 launches it on all devices:

1. why the difference in devices/android versions?
2. should the context not be the same? I know Application Context & View context are different. But not sure why this should work. I know I should not be using getApplicationContext() for a view.. But still a little confused.

(Please note MyTestActivity is a subclass of MyActivity)

Edit: In option #1 the MyActivity gets the Context from a class variable and uses that to launch the dialog.
In option #2 MyTestActivity gets the context (should be same context as MyActivity?) and passes that into the showMessage. (showMessage takes a new parameter in example #2)

Example #1

///////////////////////////////////////////
// THIS Example works on Galaxy Nexus, but not on some other devices, such as : 
// SAMSUNG-SGH-I997. (infuse) - this just simply does not display anything.

public class MyTestActivity extends MyActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.my_layout);
        Intent i = new Intent(MyTestActivity.this, ActivityTwo.class);
        startActivityForResult(i, Constants.FROM_ACTIVITY);
    }

    @Override 
    public void onActivityResult(int requestCode, int resultCode, Intent data) {     
        super.onActivityResult(requestCode, resultCode, data); 
        IntentResult intentResult = IntentIntegrator.parseActivityResult(requestCode, 
                   resultCode, data);
        if ((intentResult != null) && (resultCode == RESULT_OK)) {
             playsound(SOUND_DING); // User hears this - SoundPool
             showMessage("Test Title","Test Message"); // User does not see message
        }
    }
}

public class MyActivity extends Activity {
    private Context mContext;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mContext=this;
    }

    public void showMessage(String title, String message) {
        AlertDialog.Builder builder = new AlertDialog.Builder(mContext);
    builder.setTitle(title);
    builder.setMessage(message)
               .setPositiveButton(mContext.getString(R.string.ok), 
                new DialogInterface.OnClickListener() {
                   public void onClick(DialogInterface dialog, int id) {

                            finish();

                   }
               });
    AlertDialog alert = builder.create();
    alert.show();
    }
}

And example #2

/////////////////////////////////////////////////////////////
// This works on all devices
    public class MyTestActivity extends MyActivity {
        private Context context;
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.my_layout);
            context = this;
        Intent i = new Intent(MyTestActivity.this, ActivityTwo.class);
        startActivityForResult(i, Constants.FROM_ACTIVITY);
        }

        @Override 
        public void onActivityResult(int requestCode, int resultCode, Intent data) {     
            super.onActivityResult(requestCode, resultCode, data); 
            IntentResult intentResult = IntentIntegrator.parseActivityResult(requestCode, 
                       resultCode, data);
            if ((intentResult != null) && (resultCode == RESULT_OK)) {
                 playsound(SOUND_DING); // user hears this
                 showMessage("Test Title","Test Message", context); // user sees this
            }
        }
    }

    public class MyActivity extends Activity {
        private Context mContext;
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            mContext=this;
        }

        public void showMessage(String title, String message, Context context) {
            AlertDialog.Builder builder = new AlertDialog.Builder(context);
        builder.setTitle(title);
        builder.setMessage(message)
                   .setPositiveButton(context.getString(R.string.ok), 
                    new DialogInterface.OnClickListener() {
                       public void onClick(DialogInterface dialog, int id) {

                                finish();

                       }
                   });
        AlertDialog alert = builder.create();
        alert.show();
        }
    }

Answer 1

The answer is simple. If you don’t call super.onCreate(savedInstanceState); in your overriden onCreate() you get a garbage instead of context. If you call super.onCreate(savedInstanceState);, you get a working context.