Question

我的项目运行良好，就在今天，我已经升级了Flutter，然后一切开始运行。

最底层的是他们给我的错误。请帮助我。

file:///Users/macbook/Documents/flutter/.pub-cache/hosted/pub.dartlang.org/animated_background-1.0.4/lib/image_helper.dart:17:30: Error: The argument type 'dynamic Function(ImageInfo, bool)' can't be assigned to the parameter type 'ImageStreamListener'.
 - 'ImageInfo' is from 'package:flutter/src/painting/image_stream.dart' ('file:///Users/macbook/Documents/flutter/packages/flutter/lib/src/painting/image_stream.dart').
 - 'ImageStreamListener' is from 'package:flutter/src/painting/image_stream.dart' ('file:///Users/macbook/Documents/flutter/packages/flutter/lib/src/painting/image_stream.dart').
Try changing the type of the parameter, or casting the argument to 'ImageStreamListener'.
    newStream.removeListener(listener);
                             ^
file:///Users/macbook/Documents/flutter/.pub-cache/hosted/pub.dartlang.org/animated_background-1.0.4/lib/image_helper.dart:20:25: Error: The argument type 'dynamic Function(ImageInfo, bool)' can't be assigned to the parameter type 'ImageStreamListener'.
 - 'ImageInfo' is from 'package:flutter/src/painting/image_stream.dart' ('file:///Users/macbook/Documents/flutter/packages/flutter/lib/src/painting/image_stream.dart').
 - 'ImageStreamListener' is from 'package:flutter/src/painting/image_stream.dart' ('file:///Users/macbook/Documents/flutter/packages/flutter/lib/src/painting/image_stream.dart').
Try changing the type of the parameter, or casting the argument to 'ImageStreamListener'.
  newStream.addListener(listener);
                        ^
file:///Users/macbook/Documents/flutter/.pub-cache/hosted/pub.dartlang.org/animated_background-1.0.4/lib/image_helper.dart:21:41: Error: The argument type 'dynamic Function(ImageInfo, bool)' can't be assigned to the parameter type 'ImageStreamListener'.
 - 'ImageInfo' is from 'package:flutter/src/painting/image_stream.dart' ('file:///Users/macbook/Documents/flutter/packages/flutter/lib/src/painting/image_stream.dart').
 - 'ImageStreamListener' is from 'package:flutter/src/painting/image_stream.dart' ('file:///Users/macbook/Documents/flutter/packages/flutter/lib/src/painting/image_stream.dart').
Try changing the type of the parameter, or casting the argument to 'ImageStreamListener'.
  return () => newStream.removeListener(listener);
                                        ^
Compiler failed on /Users/macbook/AndroidStudioProjects/alimmentation/lib/main.dart
Finished with error: Gradle task assembleDebug failed with exit code 1

Answer 1

通过替换解决了类似的问题

/*...*/.addListener((ImageInfo image, bool synchronousCall) { /*...*/ });

使用

import 'package:flutter/painting.dart';

/*...*/.addListener(new ImageStreamListener((ImageInfo image, bool synchronousCall) { /*...*/ }) as ImageStreamListener);

Answer 2

我遇到了同样的问题，这里只是一些示例代码

破解代码：

var sunImage = new NetworkImage(incident.mobileSignature[0].uriFile,
          headers: AuthenticationService.getAuthHeaders());
sunImage.obtainKey(new ImageConfiguration()).then((val) {
    var load = sunImage.load(val);
    load.addListener((listener, err) async {
        ByteData data = await listener.image.toByteData(format:ui.ImageByteFormat.png);
        setState(() => this.signatureImage = data);
    });
  });
}

代码在load.addListener((listener, err) async { ....行上中断

我解决了创建一个ImageListener函数的问题，该函数与我以前使用listener变量的函数相同。然后创建一个ImageStreamListener来接收此ImageListener作为参数。还要注意，您可以将参数onError和onChunk发送到ImageStreamListener。

var sunImage = new NetworkImage(incident.mobileSignature[0].uriFile,
          headers: AuthenticationService.getAuthHeaders());
sunImage.obtainKey(new ImageConfiguration()).then((val) {
    var load = sunImage.load(val);
    ImageListener imageListener = (ImageInfo imageInfo, syncCall) async {
        ByteData data =
              await imageInfo.image.toByteData(format: ui.ImageByteFormat.png);
          setState(() => this.signatureImage = data);
    };
    ImageStreamListener listenerStream = new ImageStreamListener(imageListener);
    load.addListener(listenerStream, onError: ...., onChunk: ......); // These last parameters are optional
});

Answer 3

将animated_background文件中的pubspec.yaml依赖项更改为以下内容：

animated_background:
    git: https://github.com/AndreBaltazar8/flutter_animated_background.git

随后执行flutter clean并重建。

原因：之所以发生这种情况，是因为该依赖关系实际上已经在存储库中进行了更改，以匹配与Image API相关的某些框架更改，但在pub.dev中却没有。

Answer 4

在Flutter打印插件中遇到ImageStreamListener错误。我正在使用Flutter 1.5.4修补程序2版本。

使用打印：2.0.2＃修复此版本以解决ImageStreamListener问题。

希望有帮助

升级后Flutter不再起作用

4 个答案: