不停地切换两张图片ViewFlipper

<ViewFlipper android:layout_height="fill_parent"
android:layout_width="fill_parent"
android:inAnimation="@anim/in_lefttoright"
android:outAnimation="@anim/out_lefttoright"
android:flipInterval="500"
android:autoStart="true"> 
<ImageView android:layout_height="fill_parent"
android:layout_width="fill_parent"
android:src="@drawable/playingbg"/> 
<ImageView android:src="@drawable/playingbg"
android:layout_width="fill_parent"
android:layout_height="fill_parent"/> 
</ViewFlipper>

android:flipInterval="500"：切换时间间隔

android:autoStart="true"：自动切换