QuickReturnListView.java

package com.fima.cardsui.views;

import android.content.Context;
import android.util.AttributeSet;
import android.view.View;
import android.widget.ListView;

public class QuickReturnListView extends ListView {

	private int mItemCount;
	private int mItemOffsetY[];
	private boolean scrollIsComputed = false;
	private int mHeight;

	public QuickReturnListView(Context context) {
		super(context);
	}

	public QuickReturnListView(Context context, AttributeSet attrs) {
		super(context, attrs);
	}

	public int getListHeight() {
		return mHeight;
	}

	public void computeScrollY() {
		mHeight = 0;
		try {
			mItemCount = getAdapter().getCount();
			if (mItemOffsetY == null) {
				mItemOffsetY = new int[mItemCount];
			}
			for (int i = 0; i < mItemCount; ++i) {
				View view = getAdapter().getView(i, null, this);
				view.measure(
						MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED),
						MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
				mItemOffsetY[i] = mHeight;
				mHeight += view.getMeasuredHeight();
			}
			scrollIsComputed = true;
		} catch (NullPointerException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}

	public boolean scrollYIsComputed() {
		return scrollIsComputed;
	}

	public int getComputedScrollY() {
		int pos, nScrollY, nItemY;
		View view = null;
		pos = getFirstVisiblePosition();
		view = getChildAt(0);
		nItemY = view.getTop();
		nScrollY = mItemOffsetY[pos] - nItemY;
		return nScrollY;
	}
}