Question

在Flutter升级v3.13之后，我在vscode调试控制台中得到以下错误运行项目：

Invalid depfile: C:\Users\DIMAS\FlutterCode\skip\.dart_tool\flutter_build\35269fa8986c9ee7a9c97697217003ec\kernel_snapshot.d
Invalid depfile: C:\Users\DIMAS\FlutterCode\skip\.dart_tool\flutter_build\35269fa8986c9ee7a9c97697217003ec\kernel_snapshot.d
Error: Could not resolve the package 'characters' in 'package:characters/characters.dart'.
/C:/src/flutter/packages/flutter/lib/src/material/text_field.dart:9:8: Error: Not found: 'package:characters/characters.dart'
import 'package:characters/characters.dart';
       ^
/C:/src/flutter/packages/flutter/lib/widgets.dart:18:1: Error: Not found: 'package:characters/characters.dart'
export 'package:characters/characters.dart';
^
/C:/src/flutter/packages/flutter/lib/src/rendering/editable.dart:10:8: Error: Not found: 'package:characters/characters.dart'
import 'package:characters/characters.dart';
       ^
/C:/src/flutter/packages/flutter/lib/src/services/text_formatter.dart:9:8: Error: Not found: 'package:characters/characters.dart'
import 'package:characters/characters.dart';
       ^
/C:/src/flutter/.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:88:26: Error: Type 'DiagnosticableMixin' not found.
class PictureStream with DiagnosticableMixin {
                         ^^^^^^^^^^^^^^^^^^^
/C:/src/flutter/.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:192:44: Error: Type 'DiagnosticableMixin' not found.
abstract class PictureStreamCompleter with DiagnosticableMixin {
                                           ^^^^^^^^^^^^^^^^^^^
/C:/src/flutter/.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:88:7: Error: The type 'DiagnosticableMixin' can't be mixed in.
class PictureStream with DiagnosticableMixin {
      ^
/C:/src/flutter/.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:192:16: Error: The type 'DiagnosticableMixin' can't be mixed in.
abstract class PictureStreamCompleter with DiagnosticableMixin {
               ^
/C:/src/flutter/packages/flutter/lib/src/material/text_field.dart:822:61: Error: The getter 'characters' isn't defined for the class 'String'.
Try correcting the name to the name of an existing getter, or defining a getter or field named 'characters'.
  int get _currentLength => _effectiveController.value.text.characters.length;
                                                            ^^^^^^^^^^
/C:/src/flutter/packages/flutter/lib/src/material/text_field.dart:824:118: Error: The getter 'characters' isn't defined for the class 'String'.
Try correcting the name to the name of an existing getter, or defining a getter or field named 'characters'.
  bool get _hasIntrinsicError => widget.maxLength != null && widget.maxLength > 0 && _effectiveController.value.text.characters.length > widget.maxLength;
                                                                                                                     ^^^^^^^^^^
/C:/src/flutter/packages/flutter/lib/src/rendering/editable.dart:244:64: Error: The getter 'characters' isn't defined for the class 'String'.
Try correcting the name to the name of an existing getter, or defining a getter or field named 'characters'.
       assert(obscuringCharacter != null && obscuringCharacter.characters.length == 1),
                                                               ^^^^^^^^^^
/C:/src/flutter/packages/flutter/lib/src/rendering/editable.dart:361:35: Error: The getter 'characters' isn't defined for the class 'String'.
Try correcting the name to the name of an existing getter, or defining a getter or field named 'characters'.
    assert(value != null && value.characters.length == 1);
                                  ^^^^^^^^^^
/C:/src/flutter/packages/flutter/lib/src/rendering/editable.dart:567:11: Error: 'Characters' isn't a type.
    final Characters remaining = string.characters.skipWhile((String currentString) {
          ^^^^^^^^^^
/C:/src/flutter/packages/flutter/lib/src/rendering/editable.dart:567:41: Error: The getter 'characters' isn't defined for the class 'String'.
Try correcting the name to the name of an existing getter, or defining a getter or field named 'characters'.
    final Characters remaining = string.characters.skipWhile((String currentString) {
                                        ^^^^^^^^^^
/C:/src/flutter/packages/flutter/lib/src/rendering/editable.dart:600:47: Error: The getter 'characters' isn't defined for the class 'String'.
Try correcting the name to the name of an existing getter, or defining a getter or field named 'characters'.
    for (final String currentString in string.characters) {
                                              ^^^^^^^^^^
/C:/src/flutter/packages/flutter/lib/src/rendering/editable.dart:602:40: Error: The getter 'characters' isn't defined for the class 'String'.
Try correcting the name to the name of an existing getter, or defining a getter or field named 'characters'.
          !_isWhitespace(currentString.characters.first.toString().codeUnitAt(0))) {
                                       ^^^^^^^^^^
/C:/src/flutter/.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:167:11: Error: Superclass has no method named 'debugFillProperties'.
    super.debugFillProperties(properties);
          ^^^^^^^^^^^^^^^^^^^
/C:/src/flutter/.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:171:30: Error: The method 'toStringShort' isn't defined for the class 'PictureStreamCompleter'.
 - 'PictureStreamCompleter' is from 'package:flutter_svg/src/picture_stream.dart' ('/C:/src/flutter/.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart').
Try correcting the name to the name of an existing method, or defining a method named 'toStringShort'.
      ifPresent: _completer?.toStringShort(),
                             ^^^^^^^^^^^^^
/C:/src/flutter/.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:266:11: Error: Superclass has no method named 'debugFillProperties'.
    super.debugFillProperties(description);
          ^^^^^^^^^^^^^^^^^^^
/C:/src/flutter/packages/flutter/lib/src/services/text_formatter.dart:355:11: Error: 'CharacterRange' isn't a type.
    final CharacterRange iterator = CharacterRange(value.text);
          ^^^^^^^^^^^^^^
/C:/src/flutter/packages/flutter/lib/src/services/text_formatter.dart:355:37: Error: Method not found: 'CharacterRange'.
    final CharacterRange iterator = CharacterRange(value.text);
                                    ^^^^^^^^^^^^^^
/C:/src/flutter/packages/flutter/lib/src/services/text_formatter.dart:356:20: Error: The getter 'characters' isn't defined for the class 'String'.
Try correcting the name to the name of an existing getter, or defining a getter or field named 'characters'.
    if (value.text.characters.length > maxLength) {
                   ^^^^^^^^^^
/C:/src/flutter/packages/flutter/lib/src/services/text_formatter.dart:375:61: Error: The getter 'characters' isn't defined for the class 'String'.
Try correcting the name to the name of an existing getter, or defining a getter or field named 'characters'.
    if (maxLength != null && maxLength > 0 && newValue.text.characters.length > maxLength) {
                                                            ^^^^^^^^^^
/C:/src/flutter/packages/flutter/lib/src/services/text_formatter.dart:378:25: Error: The getter 'characters' isn't defined for the class 'String'.
Try correcting the name to the name of an existing getter, or defining a getter or field named 'characters'.
      if (oldValue.text.characters.length == maxLength) {
                        ^^^^^^^^^^

Unhandled exception:
FileSystemException(uri=org-dartlang-untransla
table-uri:package%3Acharacters%2Fcharacters.dart; message=StandardFileSystem only supports file:* and data:* URIs)
[38;5;248m#0      StandardFileSystem.entityForUri  (package:front_end/src/api_prototype/standard_file_system.dart:33:7)[39;49m

[38;5;248m#1      asFileUri  (package:vm/kernel_front_end.dart:659:37)[39;49m
[38;5;248m#2      writeDepfile  (package:vm/kernel_front_end.dart:853:21)[39;49m
<asynchronous suspen
sion>
[38;5;248m#3      FrontendCompiler.compile  (package:frontend_server/frontend_server.dart:574:15)[39;49m
[38;5;244m<asynchronous suspension>[39;49m
#4      _FlutterFrontendCompiler.compile (packa
ge:flutter_frontend_server/server.dart:43:22)
[38;5;248m#5      starter  (package:flutter_frontend_server/server.dart:182:27)[39;49m

#6      main (file:///C:/b/s/w/ir/cache/builder/src/flut
ter/flutter_frontend_server/bin/starter.dart:9:30)
[38;5;244m#7      _startIsolate.<anonymous closure>  (dart:isolate-patch/isolate_patch.dart:299:32)[39;49m
#8      _RawReceivePortImpl
._handleMessage (dart:isolate-patch/isolate_patch.dart:168:12)

失败：构建失败，并出现异常。

其中：脚本'C：\ src \ flutter \ packages \ flutter_tools \ gradle \ flutter.gradle'行：896
出了什么问题：任务'：app：compileFlutterBuildDebug'的执行失败。

处理'命令'C：\ src \ flutter \ bin \ flutter.bat'结束时退出值非零

尝试：使用--stacktrace选项运行以获取堆栈跟踪。使用--info或--debug选项运行，以获取更多日志输出。使用--scan运行以获取完整的见解。
在https://help.gradle.org
获得更多帮助

57秒内失败异常：Gradle任务assembleDebug失败，退出代码为1

它似乎缺少character.dart和一些gradle的东西，但是我现在在Google上找不到确切的问题和答案，

但是，如果我制作并运行一个新项目，则没有任何错误，我的pubspec.yaml（我将旧项目和新项目pubspec.yaml进行了比较，对于其他软件包，没有显着不同的说法）：

Answer 1

您似乎在pubspec.yaml中缺少字符包。

确保它在那里并且您的pubspec格式正确。然后再次运行flutter pub get。

如果失败，则应运行flutter pub cache repair

Answer 2

有同样的问题。

在pubspec.yaml中，只需执行flutter pub get和flutter pub upgrade。

然后在根目录终端中执行flutter clean，它将毫无问题地运行。

Answer 3

在更新flutter SDK之后，我的flutter应用程序也遇到了类似的问题。

解决我的问题的方法是执行以下操作。

打开终端（CMD），导航至pubspec.yaml所在的flutter项目。运行以下命令：

解决方案

flutter pub get

flutter pub upgrade

在那之后，如果仍然有问题，可以运行flutter pub cache repair，但是

flutter clean

帮我解决了这个问题。

为了确定，我重新启动了Visual Studio和AVD虚拟设备重新开始。

我使用哪些工具和软件：

Visual Studio代码1.47.3

Android Studio 4.0.1（Android虚拟设备）

Flutter 1.20.1（发布日期6.8.2020）

Dart 2.9.0

Answer 4

刷新flutter pub get后，我遇到了SVG问题，并且将flutter_svg: ^0.17.4更新为flutter_svg: ^0.18.0，从而解决了SVG问题，

Answer 5

在新的flutter版本上运行flutter upgrade后，我遇到了几次此问题。就我而言，解决方案与错误无关。只是过时的依赖关系。

我首先进行了flutter clean（来自Flutter> Flutter清理工具的IntelliJ / Android Studio。）

将我的pubspec.yaml依赖项更新到最新版本，并运行flutter pub upgrade

完成！现在您应该可以构建并运行

Answer 6

在终端中尝试

$     flutter clean

之后

$     flutter doctor

应该可以解决您的问题

Answer 7

我遇到了同样的问题，在删除.dart_tool目录/文件夹并再次运行该应用程序之后，问题得以解决

升级到v3.13后错误运行当前项目

7 个答案: