gistfile1.java

public class IndexXlistView extends XListView {
  
	private boolean mIsFastScrollEnabled = false;
	private IndexScroller mScroller = null;
	private GestureDetector mGestureDetector = null;
	
	public IndexXlistView(Context context) {
		super(context);
		// TODO Auto-generated constructor stub
	}
	
	public IndexXlistView(Context context, AttributeSet attrs) {
		super(context, attrs);
		// TODO Auto-generated constructor stub
	}

	public IndexXlistView(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
		// TODO Auto-generated constructor stub
	}
	
	@Override
	public void setFastScrollEnabled(boolean enabled) {
		mIsFastScrollEnabled = enabled;
		if (mIsFastScrollEnabled) {
			if (mScroller == null)
				mScroller = new IndexScroller(getContext(), this);

		} else {
			if (mScroller != null) {
				mScroller.hide();
				mScroller = null;
			}
		}
		
	}
	
	@Override
	public void draw(Canvas canvas) {
		super.draw(canvas);
		if (mScroller != null)
			mScroller.draw(canvas);
	}
	
	@Override
	public boolean onTouchEvent(MotionEvent ev) {
		// TODO Auto-generated method stub
		if (mScroller != null && mScroller.onTouchEvent(ev))
			return true;
		
		if (mGestureDetector == null) {
			mGestureDetector = new GestureDetector(getContext(), new GestureDetector.SimpleOnGestureListener() {

				@Override
				public boolean onFling(MotionEvent e1, MotionEvent e2,
						float velocityX, float velocityY) {
					// If fling happens, index bar shows
					if(isFastScrollEnabled()){
						mScroller.show();
					}
					return super.onFling(e1, e2, velocityX, velocityY);
				}
				
			});
		}
		mGestureDetector.onTouchEvent(ev);
		return super.onTouchEvent(ev);
	}
	
	@Override
	public boolean isFastScrollEnabled() {
		return mIsFastScrollEnabled;
	}
	
	@Override
	public boolean onInterceptTouchEvent(MotionEvent ev) {
		return true;
	}

	@Override
	public void setAdapter(ListAdapter adapter) {
		super.setAdapter(adapter);
		if (mScroller != null)
			mScroller.setAdapter(adapter);
		
	}

	@Override
	protected void onSizeChanged(int w, int h, int oldw, int oldh) {
		super.onSizeChanged(w, h, oldw, oldh);
		if (mScroller != null)
			mScroller.onSizeChanged(w, h, oldw, oldh);
		
	}
	
}