LocalResourceFetchProducer.java 文件源码

private int getLength(ImageRequest imageRequest) {
  AssetFileDescriptor fd = null;
  try {
    fd = mResources.openRawResourceFd(getResourceId(imageRequest));
    return (int) fd.getLength();
  } catch (Resources.NotFoundException e) {
    return -1;
  } finally {
    try {
      if (fd != null) {
        fd.close();
      }
    } catch (IOException ignored) {
      // There's nothing we can do with the exception when closing descriptor.
    }
  }
}