Null Pointer implementing Android Wheel

Question

I'm trying to implement Yuri Kanivets' Android wheel picker. I am simply trying to place a few strings onto a single wheel. What makes my implementation a little different is that I am trying to display the wheel on an AlertDialog.Builder. I can get an empty wheel to appear on my dialog, but I can't seem to populate it with anything. Every time I try to add values to the wheel, I get a null pointer exception.

If anyone is familiar with this, can you see what I am doing wrong? I strongly suspect that the context that I am using in my ArrayWheelAdapter is wrong, but I don't know how else to do it. Here is my code:

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_find_events);

    LayoutInflater inflater = LayoutInflater.from(this);
    builderView = inflater.inflate(R.layout.wheel_range_layout, null);
    AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder.setView(builderView);       
    alert = builder.create();

    final WheelView range = (WheelView) findViewById(R.id.range);
    int defaultRange = 0;
    String ranges[] = new String[] {"10 miles", "25 miles", "50 miles", "Everywhere"};

    ArrayWheelAdapter<String> adapter = new ArrayWheelAdapter<String>(this, ranges);
    adapter.setTextSize(18);

    //this next line is where it is crashing -- maybe adapter is null???
    range.setViewAdapter(adapter);
    range.setCurrentItem(defaultRange);

    alert.show();
}

Answer 1

use

final WheelView range = (WheelView)builderView. findViewById(R.id.range);

instead of

final WheelView range = (WheelView) findViewById(R.id.range);

for initializing WheelView range instance because WheelView View is in DialogBox wheel_range_layout layout instead of Activity layout