/** * 獲取 raw 下 指定視頻文件的縮略圖 * @param aVideoName  * @return */private Drawable getThumbnail(String aVideoName){  Drawable ret = null;  int id = 0;  try  {    id = R.raw.class.getDeclaredField(aVideoName).getInt(this);    Uri videoURI = Uri.parse("android.resource://" + this.getPackageName() + "/" + id);    ret = getThumbnail(videoURI);  } catch ( IllegalAccessException aE )  {    aE.printStackTrace();  } catch ( NoSuchFieldException aE )  {    aE.printStackTrace();  }  return ret;}private Drawable getThumbnail(Uri aVideoUri){  MediaMetadataRetriever retriever = new MediaMetadataRetriever();  retriever.setDataSource(this, aVideoUri);  Bitmap bitmap = retriever      .getFrameAtTime(1*1000*1000, MediaMetadataRetriever.OPTION_PREVIOUS_SYNC);  Drawable drawable = new BitmapDrawable(getResources(), bitmap);  return drawable;}