引用：http://blog.csdn.net/leilu2008/article/details/6458753
bgimg0 = getImageFromAssetsFile("Cat_Blink/cat_blink0000.png");
/**
* 从Assets中读取图片
*/
private Bitmap getImageFromAssetsFile(String fileName)
{
Bitmap image = null;
AssetManager am = getResources().getAssets();
try
{
InputStream is = am.open(fileName);
image = BitmapFactory.decodeStream(is);
is.close();
}
catch (IOException e)
{
e.printStackTrace();
}
return image;
}