flutter view 保存图片代码

Future<String> capturePng() async {
  RenderRepaintBoundary boundary =
  key.currentContext!.findRenderObject() as RenderRepaintBoundary;
  ui.Image image = await boundary.toImage();
  ByteData? byteData =
  await (image.toByteData(format: ui.ImageByteFormat.png));
  if (byteData != null) {
    await ImageGallerySaver.saveImage(byteData.buffer.asUint8List());
  }
  return "";
}