[androidUI特效]android中TextView中如何设置水平滚动效果

package irdc.ScrollingText;
import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;
public class ScrollingText extends Activity
{
  public TextView t1;
  /** Called when the activity is first created. */
  @Override
  public void onCreate(Bundle savedInstanceState)
  {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    t1= (TextView) findViewById(R.id.t1);
    t1.setText("哈哈我的跑马灯程序接下来是歌词呵呵：沉鱼落雁，闭月羞花，美的无处藏，人在身旁，如沐春光");
    t1.setTextSize(30);
    t1.setHorizontallyScrolling(true);
    t1.setFocusable(true);
  }
}

<?xml version="1.0" encoding="utf-8"?>
<AbsoluteLayout
android:id="@+id/widget35"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="@drawable/black"
xmlns:android="http://schemas.android.com/apk/res/android"
>
<TextView
android:id="@+id/t1"
android:layout_width="100px"//此处为文本显示区域的宽度此值必须比你的文本宽度要小否则是没有效果的
android:layout_height="wrap_content"
android:text="@string/str_id"
android:textColor="@drawable/green"
android:layout_x="61px"
android:layout_y="69px"
android:scrollX="2px"
android:singleLine="true"
android:ellipsize="marquee"
android:marqueeRepeatLimit="marquee_forever"
>
</TextView>
<ViewStub android:layout_y="221dip" android:layout_;wrap_content" android:layout_x="103dip" android:id="@+id/ViewStub01" android:layout_height="wrap_content"></ViewStub>
</AbsoluteLayout>