以wallpaper 选择框为例，当在Launcher workspace的空白区域上长按，会弹出wallpaper的选择框，选择框的标题为”Choose wallpaper from”，如下：
代码如下:
private void startWallpaper() {
showWorkspace(true);
final Intent pickWallpaper = new Intent(Intent.ACTION_SET_WALLPAPER);
Intent chooser = Intent.createChooser(pickWallpaper, getText(R.string.chooser_wallpaper));
// NOTE: Adds a configure option to the chooser if the wallpaper supports it
startActivityForResult(chooser, REQUEST_PICK_WALLPAPER);
}
其中，R.string.chooser_wallpaper对应的字串内容就是”Choose wallpaper from”，定义在Launcher2的Strings.xml中