findViewById returns null when moved into a library file

Question

I'm new to Java and Android. I have a piece of code that is used for multiple activities so I moved it into its own library .java file. However, now my findViewById return null where they used to return the right stuff when they were part of the main Activity file with onCreate() and setContentView() calls. How do I make it work inside my library?

Call from the Activity class:

helper.popupControl(getListView(), getBaseContext(), "on");

The code in the libruary:

public class Helper extends ListActivity {

public void popupControl (View v, Context context, String on_off) {


    Animation aFilm = AnimationUtils.loadAnimation(context, R.anim.fade_in);  
    aFilm.reset();


    View vFilm = (View) v.findViewById(R.id.gray_out_film);

    if(vFilm==null) { 
        Toast maxToast = Toast.makeText(context, "View is null! "+R.id.gray_out_film+", View:"+v.toString(), Toast.LENGTH_LONG);
        maxToast.setGravity(Gravity.CENTER, 0, 0);
        maxToast.show(); 
    } else {
        Toast maxToast = Toast.makeText(context, "View is not null!", Toast.LENGTH_SHORT);
        maxToast.setGravity(Gravity.CENTER, 0, 0);
        maxToast.show();
    }



}

}

Answer 1

What you're trying to do seems 'icky' but here's how it would be done.

You'll need to pass the View from the Activity...findViewbyId() is its Member function.

If you provide some sample code, i could be more helpfull.

Edit: Confused Context with View. Oops!