read method

@override Future<int> read(int offset, Uint8List buffer)

Implementation

@override
Future<int> read(int offset, Uint8List buffer) => _serialize(() async {
      if (offset < 0) throw RangeError.value(offset, 'offset');
      final image = _image;
      if (image != null) {
        if (offset >= image.length) return 0;
        final count = buffer.length < image.length - offset
            ? buffer.length
            : image.length - offset;
        buffer.setRange(0, count, image, offset);
        return count;
      }
      await _file.setPosition(offset);
      return _file.readInto(buffer);
    });