Flutter怎么在HarmonyOS鸿蒙Next中把图片保存到手机相册

【解决方案】

image_gallery_saver是一个Flutter插件，用于将图片或者视频保存到设备相册。由于Flutter的image_picker插件只能选择图片而无法保存图片到相册，此插件提供了该功能。以下提供4种方式保存图片或者视频到设备相册。

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: Text("Save image to gallery"),
        ),
        body: Center(
          child: Column(
            children: <Widget>[
              SizedBox(height: 15),
              // `RepaintBoundary` 的作用是将这个蓝色矩形的绘制区域隔离出来，以便在需要时可以独立处理它的绘制和重绘。`_globalKey` 则用于在代码的其他部分访问这个 `RepaintBoundary` 小部件。
              RepaintBoundary(
                key: _globalKey,
                child: Container(
                  alignment: Alignment.center,
                  width: 300,
                  height: 300,
                  color: Colors.blue,
                ),
              ),
              Container(
                padding: EdgeInsets.only(top: 15),
                child: ElevatedButton(
                  onPressed: _saveLocalImage,
                  child: Text("Save Local Image"),
                ),
                width: 300,
                height: 44,
              ),
              Container(
                padding: EdgeInsets.only(top: 15),
                child: ElevatedButton(
                  onPressed: _saveNetworkImage,
                  child: Text("Save Network Image"),
                ),
                width: 300,
                height: 44,
              ),
              Container(
                padding: EdgeInsets.only(top: 15),
                child: ElevatedButton(
                  onPressed: _saveNetworkGifFile,
                  child: Text("Save Network Gif Image"),
                ),
                width: 300,
                height: 44,
              ),
              Container(
                padding: EdgeInsets.only(top: 15),
                child: ElevatedButton(
                  onPressed: _saveNetworkVideoFile,
                  child: Text("Save Network Video"),
                ),
                width: 300,
                height: 44,
              ),
            ],
          ),
        ));
  }

保存本地图片到相册，参考代码如下：

  GlobalKey _globalKey = GlobalKey();  // 创建一个`GlobalKey`类型的全局键对象，并将其赋值给变量 `_globalKey`
  // 从指定的Widget中获取渲染对象（Render Object），然后将该Widget的内容转换成一个图像（Image）
  _saveLocalImage() async {
    RenderRepaintBoundary boundary =
        _globalKey.currentContext!.findRenderObject() as RenderRepaintBoundary;
    ui.Image image = await boundary.toImage();
    ByteData? byteData =
        await (image.toByteData(format: ui.ImageByteFormat.png));
    if (byteData != null) {
      final result =
          await ImageGallerySaver.saveImage(byteData.buffer.asUint8List());
      print(result);
      Utils.toast(result.toString());
    }
  }

保存网络图片到相册，参考代码如下：

  _saveNetworkImage() async {
    var response = await Dio().get(
        "https://example.jpg",
        options: Options(responseType: ResponseType.bytes));
    final result = await ImageGallerySaver.saveImage(
        Uint8List.fromList(response.data),
        quality: 60,
        name: "hello");
    print(result);
    Utils.toast("$result");
  }

保存网络gif图到相册，参考代码如下：

  _saveNetworkGifFile() async {
    var appDocDir = await getTemporaryDirectory();
    String savePath = appDocDir.path + "/temp.gif";
    String fileUrl =
        "https://example.gif";
    await Dio().download(fileUrl, savePath);
    final result =
        await ImageGallerySaver.saveFile(savePath, isReturnPathOfIOS: true);
    print(result);
    Utils.toast("$result");
  }

保存网络video到相册，参考代码如下：

  _saveNetworkVideoFile() async {
    var appDocDir = await getTemporaryDirectory();
    String savePath = appDocDir.path + "/temp.mp4";
    String fileUrl =
        "https://example.mp4";
    await Dio().download(fileUrl, savePath, onReceiveProgress: (count, total) {
      print((count / total * 100).toStringAsFixed(0) + "%");
    });
    final result = await ImageGallerySaver.saveFile(savePath);
    print(result);
    Utils.toast("$result");
  }