/* ownCloud Android client application
 *   Copyright (C) 2012 Bartek Przybylski
 *   Copyright (C) 2012-2013 ownCloud Inc.
 *
 *   This program is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License version 2,
 *   as published by the Free Software Foundation.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

package com.owncloud.android.ui;

import android.content.Context;
import android.graphics.Canvas;
import android.util.AttributeSet;
import android.widget.GridView;

/**
 * GridView allowing to specify the position of an item that should be top left in the visible area, if possible.
 * 
 * The cleanest way I found to overcome the problem due to getHeight() returns 0 until the view is really drawn. 
 *  
 * @author David A. Velasco
 */
public class ExtendedListView extends GridView {

    private int mPositionToSetTopLeft;

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

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

    public ExtendedListView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }
    
    /**
     * {@inheritDoc}
     * 
     * 
     */
    @Override
    protected void onDraw (Canvas canvas) {
        super.onDraw(canvas);
        if (mPositionToSetTopLeft > 0) {
            this.smoothScrollToPosition(mPositionToSetTopLeft);
            mPositionToSetTopLeft = 0;
        }
    }
    
    /**
     * Public method to set the position of the item that should be top left in the visible area of the view.
     * 
     * The position is saved here and checked in onDraw().
     *  
     * @param position         Position (in the list of items) of the item to be top left in the visible area.     
     */
    public void setSelectionAsTopLeft(int position) {
        mPositionToSetTopLeft = position;
    }
}