handler.postDelayed()和timerTask

public static void scrollToListviewTop(final XListView listView)

{

listView.smoothScrollToPosition(0);

final Handler handler = new Handler();

handler.postDelayed(new Runnable()

{

@Override

public void run()

{

if (listView.getFirstVisiblePosition() > 0)

{

listView.smoothScrollToPosition(0);

handler.postDelayed(this, 100);

}

}

}, 100);

}

public class TimeTaskScroll extends TimerTask {

private XListView listView;

public TimeTaskScroll(XListView listView){

this.listView = listView;

}

private Handler handler = new Handler() {

public void handleMessage(android.os.Message msg) {

listView.smoothScrollToPosition(0);

};

};

@Override

public void run() {

Message msg = handler.obtainMessage();

handler.sendMessageDelayed(msg, 2000);

}

}

new TimerTask().run();