设置默认壁纸

private void setDefaultWallpaper() {
if (!mWallpaperChecked) {
Drawable wallpaper = peekWallpaper();
if (wallpaper == null) {
try {
clearWallpaper();
} catch (IOException e) {
Log.e(LOG_TAG, "Failed to clear wallpaper " + e);
}
} else {
getWindow().setBackgroundDrawable(new ClippedDrawable(wallpaper));
}
mWallpaperChecked = true;
}

}

参考Android4.0.3源码sample中Home app