android实现自动滚动的Gallary控件效果

本文实例讲述了android实现自动滚动的gallary控件。分享给大家供大家参考。具体如下：

import java.util.timer;
import java.util.timertask;
import android.content.context;
import android.os.handler;
import android.util.attributeset;
import android.util.log;
import android.view.keyevent;
import android.view.motionevent;
import android.widget.gallery;
public class homegallery extends gallery
{
  /**
   * 这里的数值，限制了每次滚动的最大长度，图片宽度为480px。这里设置600效果好一些。 这个值越大，滚动的长度就越大。
   * 也就是会出现一次滚动跨多个image。这里限制长度后，每次滚动只能跨一个image
   */
  private static final int timeranimation = 1;
  private static final int time = 2000;
  private final handler mhandler = new handler()
  {
    public void handlemessage(android.os.message msg)
    {
      switch (msg.what)
      {
      case timeranimation:
        int position = getselecteditemposition();
        log.i("msg", "position:"+position);
        if (position >= (getcount() - 1))
        {
          onkeydown(keyevent.keycode_dpad_left, null);
        } else
        {
          onkeydown(keyevent.keycode_dpad_right, null);
        }
        break;
      default:
        break;
      }
    };
  };
  private final timer timer = new timer();
  private final timertask task = new timertask()
  {
    public void run()
    {
      mhandler.sendemptymessage(timeranimation);
    }
  };
  public homegallery(context paramcontext)
  {
    super(paramcontext);
    timer.schedule(task, time, time);
  }
  public homegallery(context paramcontext, attributeset paramattributeset)
  {
    super(paramcontext, paramattributeset);
    timer.schedule(task, time, time);
  }
  public homegallery(context paramcontext, attributeset paramattributeset,
      int paramint)
  {
    super(paramcontext, paramattributeset, paramint);
    timer.schedule(task, time, time);
  }
  private boolean isscrollingleft(motionevent parammotionevent1,
      motionevent parammotionevent2)
  {
    float f2 = parammotionevent2.getx();
    float f1 = parammotionevent1.getx();
    if (f2 > f1)
      return true;
    return false;
  }
  public boolean onfling(motionevent parammotionevent1,
      motionevent parammotionevent2, float paramfloat1, float paramfloat2)
  {
    int keycode;
    if (isscrollingleft(parammotionevent1, parammotionevent2))
    {
      keycode = keyevent.keycode_dpad_left;
    } else
    {
      keycode = keyevent.keycode_dpad_right;
    }
    onkeydown(keycode, null);
    return true;
  }
  public void destroy()
  {
    timer.cancel();
  }
}

希望本文所述对大家的android程序设计有所帮助。