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好吧,我什至不知道该写些什么。几个小时前一切正常。然后我看到Flutter升级可用。所以我尝试升级。那就是一切开始崩溃的时候。无论如何,我使用vpn运行终端命令。我成功了之后,我打开的每个 flutter 项目都显示此错误。
我尝试了其他项目。
我可以运行并构建apk,但是存在此错误。 这是运行命令的输出:
Launching lib\main.dart on POCOPHONE F1 in debug mode...
Running Gradle task 'assembleDebug'...
√ Built build\app\outputs\apk\debug\app-debug.apk.
Installing build\app\outputs\apk\app.apk...
D/FlutterActivity(27090): Using the launch theme as normal theme.
D/FlutterActivityAndFragmentDelegate(27090): Setting up FlutterEngine.
D/FlutterActivityAndFragmentDelegate(27090): No preferred FlutterEngine was provided. Creating a new FlutterEngine for this FlutterFragment.
D/FlutterActivityAndFragmentDelegate(27090): Attaching FlutterEngine to the Activity that owns this Fragment.
D/FlutterView(27090): Attaching to a FlutterEngine: io.flutter.embedding.engine.FlutterEngine@4b90e47
D/FlutterActivityAndFragmentDelegate(27090): Executing Dart entrypoint: main, and sending initial route: /
Debug service listening on ws://127.0.0.1:51142/_qlZxn05Q8o=/ws
Syncing files to device POCOPHONE F1...
W/.covidtrackerb(27090): Long monitor contention with owner Answers Events Handler1 (27294) at int java.lang.String.indexOf(java.lang.String, java.lang.String, int)(String.java:1742) waiters=0 in io.fabric.sdk.android.services.common.AdvertisingInfo io.fabric.sdk.android.services.common.IdManager.getAdvertisingInfo() for 1.302s
W/.covidtrackerb(27090): Long monitor contention with owner Answers Events Handler1 (27294) at int java.lang.String.indexOf(java.lang.String, java.lang.String, int)(String.java:1742) waiters=1 in io.fabric.sdk.android.services.common.AdvertisingInfo io.fabric.sdk.android.services.common.IdManager.getAdvertisingInfo() for 1.300s
D/NetworkSecurityConfig(27090): No Network Security Config specified, using platform default
E/FirebaseInstanceId(27090): binding to the service failed
E/AccessibilityBridge(27090): VirtualView node must not be the root node.
I/.covidtrackerb(27090): ProcessProfilingInfo new_methods=3224 is saved saved_to_disk=1 resolve_classes_delay=8000
E/AccessibilityBridge(27090): VirtualView node must not be the root node.
I/flutter (27090): ::Data connection is available.
E/AccessibilityBridge(27090): VirtualView node must not be the root node.
I/flutter (27090): Instance of 'Future<Response>'
I/flutter (27090): Instance of 'Future<Response>'
I/flutter (27090): size response :2
I/flutter (27090): [Instance of 'Response', Instance of 'Response']
I/flutter (27090): CovidBdState Instance of 'AllData'
E/AccessibilityBridge(27090): VirtualView node must not be the root node.
error: Undefined name 'Brightness'. (undefined_identifier at [covidtrackerbd] lib\main_screen.dart:45)
error: The method 'Color' isn't defined for the class '_HomePageState'. (undefined_method at [covidtrackerbd] lib\main_screen.dart:53)
error: The method 'Color' isn't defined for the class '_HomePageState'. (undefined_method at [covidtrackerbd] lib\main_screen.dart:58)
error: The method 'Color' isn't defined for the class '_HomePageState'. (undefined_method at [covidtrackerbd] lib\main_screen.dart:74)
error: The method 'Color' isn't defined for the class '_HomePageState'. (undefined_method at [covidtrackerbd] lib\main_screen.dart:104)
error: Undefined name 'FontWeight'. (undefined_identifier at [covidtrackerbd] lib\main_screen.dart:106)
error: The method 'Color' isn't defined for the class '_HomePageState'. (undefined_method at [covidtrackerbd] lib\main_screen.dart:113)
error: Undefined name 'FontWeight'. (undefined_identifier at [covidtrackerbd] lib\main_screen.dart:115)
error: Undefined name 'FontWeight'. (undefined_identifier at [covidtrackerbd] lib\main_screen.dart:128)
error: The method 'Color' isn't defined for the class '_HomePageState'. (undefined_method at [covidtrackerbd] lib\main_screen.dart:136)
error: Undefined name 'FontWeight'. (undefined_identifier at [covidtrackerbd] lib\main_screen.dart:213)
error: Undefined name 'FontWeight'. (undefined_identifier at [covidtrackerbd] lib\main_screen.dart:260)
error: The method 'Color' isn't defined for the class 'todo'. (undefined_method at [covidtrackerbd] lib\main_screen.dart:409)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\main_screen.dart:419)
error: The method 'Color' isn't defined for the class 'HeatMapTile'. (undefined_method at [covidtrackerbd] lib\main_screen.dart:435)
error: The method 'Color' isn't defined for the class 'HeatMapTile'. (undefined_method at [covidtrackerbd] lib\main_screen.dart:455)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\main_screen.dart:537)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\main_screen.dart:547)
error: The method 'Color' isn't defined for the class 'LoadingScreen'. (undefined_method at [covidtrackerbd] lib\screens\loadingScreen.dart:15)
error: Undefined name 'FontWeight'. (undefined_identifier at [covidtrackerbd] lib\screens\loadingScreen.dart:41)
error: Undefined name 'FontWeight'. (undefined_identifier at [covidtrackerbd] lib\screens\loadingScreen.dart:52)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\screens\loadingScreen.dart:65)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\doctors_report.dart:64)
error: Undefined name 'FontWeight'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\doctors_report.dart:68)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\doctors_report.dart:131)
error: Undefined name 'TextDecoration'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\doctors_report.dart:547)
error: Undefined name 'TextDecoration'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\doctors_report.dart:555)
error: Undefined name 'Brightness'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\formSubmissionPage.dart:24)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\formSubmissionPage.dart:81)
error: Undefined name 'FontWeight'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\formSubmissionPage.dart:85)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\formSubmissionPage.dart:95)
error: Undefined name 'TextDecoration'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\formSubmissionPage.dart:439)
error: Undefined name 'TextDecoration'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\formSubmissionPage.dart:447)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\neighbours_report.dart:58)
error: Undefined name 'FontWeight'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\neighbours_report.dart:62)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\neighbours_report.dart:102)
error: Undefined name 'TextDecoration'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\neighbours_report.dart:391)
error: Undefined name 'TextDecoration'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\neighbours_report.dart:398)
error: Undefined name 'Brightness'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\possible_affected.dart:30)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\possible_affected.dart:65)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\possible_affected.dart:85)
error: Undefined name 'Brightness'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\recurringUpdate.dart:15)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\self_reporting_page.dart:74)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\self_reporting_page.dart:94)
error: Undefined name 'Brightness'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\survey_page.dart:19)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\survey_page.dart:43)
error: Undefined name 'FontWeight'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\Report\survey_page.dart:45)
error: The method 'Color' isn't defined for the class '_SurveyPageState'. (undefined_method at [covidtrackerbd] lib\screens\tabs\Report\survey_page.dart:58)
error: The method 'Color' isn't defined for the class '_SurveyPageState'. (undefined_method at [covidtrackerbd] lib\screens\tabs\Report\survey_page.dart:102)
error: Undefined name 'Brightness'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\developerStory.dart:10)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\developerStory.dart:23)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\developerStory.dart:34)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\developerStory.dart:41)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\developerStory.dart:48)
error: Undefined class 'Color'. (undefined_class at [covidtrackerbd] lib\screens\tabs\home\constants.dart:25)
error: The function 'Color' isn't defined. (undefined_function at [covidtrackerbd] lib\screens\tabs\home\constants.dart:25)
error: Undefined class 'Color'. (undefined_class at [covidtrackerbd] lib\screens\tabs\home\constants.dart:26)
error: The function 'Color' isn't defined. (undefined_function at [covidtrackerbd] lib\screens\tabs\home\constants.dart:26)
error: The function 'Color' isn't defined. (undefined_function at [covidtrackerbd] lib\screens\tabs\home\constants.dart:27)
error: Undefined class 'Color'. (undefined_class at [covidtrackerbd] lib\screens\tabs\home\constants.dart:27)
error: Undefined class 'Color'. (undefined_class at [covidtrackerbd] lib\screens\tabs\home\constants.dart:28)
error: The function 'Color' isn't defined. (undefined_function at [covidtrackerbd] lib\screens\tabs\home\constants.dart:28)
error: The function 'Color' isn't defined. (undefined_function at [covidtrackerbd] lib\screens\tabs\home\constants.dart:29)
error: Undefined class 'Color'. (undefined_class at [covidtrackerbd] lib\screens\tabs\home\constants.dart:29)
error: The function 'Color' isn't defined. (undefined_function at [covidtrackerbd] lib\screens\tabs\home\constants.dart:30)
error: Undefined class 'Color'. (undefined_class at [covidtrackerbd] lib\screens\tabs\home\constants.dart:30)
error: Undefined class 'Color'. (undefined_class at [covidtrackerbd] lib\screens\tabs\home\constants.dart:31)
error: The function 'Color' isn't defined. (undefined_function at [covidtrackerbd] lib\screens\tabs\home\constants.dart:31)
error: The function 'Color' isn't defined. (undefined_function at [covidtrackerbd] lib\screens\tabs\home\constants.dart:33)
error: Undefined class 'Color'. (undefined_class at [covidtrackerbd] lib\screens\tabs\home\constants.dart:33)
error: Undefined class 'Color'. (undefined_class at [covidtrackerbd] lib\screens\tabs\home\constants.dart:34)
error: The function 'Color' isn't defined. (undefined_function at [covidtrackerbd] lib\screens\tabs\home\constants.dart:34)
error: Undefined class 'Color'. (undefined_class at [covidtrackerbd] lib\screens\tabs\home\constants.dart:35)
error: The function 'Color' isn't defined. (undefined_function at [covidtrackerbd] lib\screens\tabs\home\constants.dart:35)
error: The function 'Color' isn't defined. (undefined_function at [covidtrackerbd] lib\screens\tabs\home\constants.dart:36)
error: Undefined class 'Color'. (undefined_class at [covidtrackerbd] lib\screens\tabs\home\constants.dart:36)
error: Undefined name 'Brightness'. (undefined_identifier at [covidtrackerbd] lib\screens\tabs\location.dart:34)
error: Undefined name 'TextAlign'. (undefined_identifier at [covidtrackerbd] lib\screens\widgets\snackPage.dart:20)
info: Unused import: 'dart:async'. (unused_import at [covidtrackerbd] lib\main.dart:2)
info: Unused import: 'package:firebase_crashlytics/firebase_crashlytics.dart'. (unused_import at [covidtrackerbd] lib\main.dart:8)
info: Name non-constant identifiers using lowerCamelCase. (non_constant_identifier_names at [covidtrackerbd] lib\main_screen.dart:312)
info: Name types using UpperCamelCase. (camel_case_types at [covidtrackerbd] lib\main_screen.dart:395)
info: This method overrides a method annotated as @mustCallSuper in 'State', but doesn't invoke the overridden method. (must_call_super at [covidtrackerbd] lib\screens\tabs\Report\doctors_report.dart:33)
info: Unused import: 'package:covidtrackerbd/services/authentication.dart'. (unused_import at [covidtrackerbd] lib\screens\tabs\Report\possible_affected.dart:5)
info: Unused import: 'formSubmissionPage.dart'. (unused_import at [covidtrackerbd] lib\screens\tabs\Report\possible_affected.dart:9)
info: Unused import: 'package:covidtrackerbd/services/api.dart'. (unused_import at [covidtrackerbd] lib\screens\tabs\Report\self_reporting_page.dart:3)
info: Unused import: 'package:covidtrackerbd/services/json.dart'. (unused_import at [covidtrackerbd] lib\screens\tabs\Report\self_reporting_page.dart:5)
info: Unused import: 'package:flutter_html/flutter_html.dart'. (unused_import at [covidtrackerbd] lib\screens\tabs\Report\self_reporting_page.dart:8)
info: Unused import: 'package:flutter/cupertino.dart'. (unused_import at [covidtrackerbd] lib\screens\tabs\home\constants.dart:23)
info: This method overrides a method annotated as @mustCallSuper in 'AutomaticKeepAliveClientMixin', but doesn't invoke the overridden method. (must_call_super at [covidtrackerbd] lib\screens\tabs\location.dart:29)
Microsoft Windows [Version 10.0.18363.720]
(c) 2019 Microsoft Corporation. All rights reserved.
C:\Users\Momshad\Documents\GitHub\COVID-Tracker-BD-master\COVID-Tracker-BD-master\App>flutter doctor
Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel stable, v1.12.13+hotfix.8, on Microsoft Windows [Version 10.0.18363.720], locale en-001)
[√] Android toolchain - develop for Android devices (Android SDK version 29.0.2)
[√] Android Studio (version 3.6)
[√] IntelliJ IDEA Community Edition (version 2019.3)
[√] VS Code (version 1.43.1)
[!] Connected device
! No devices available
! Doctor found issues in 1 category.
C:\Users\Momshad\Documents\GitHub\COVID-Tracker-BD-master\COVID-Tracker-BD-master\App>
C:\Users\Momshad\Documents\GitHub\COVID-Tracker-BD-master\COVID-Tracker-BD-master\App>flutter doctor -v
[√] Flutter (Channel stable, v1.12.13+hotfix.8, on Microsoft Windows [Version 10.0.18363.720], locale en-001)
• Flutter version 1.12.13+hotfix.8 at C:\src\flutter
• Framework revision 0b8abb4724 (7 weeks ago), 2020-02-11 11:44:36 -0800
• Engine revision e1e6ced81d
• Dart version 2.7.0
[√] Android toolchain - develop for Android devices (Android SDK version 29.0.2)
• Android SDK at C:\Users\Momshad\AppData\Local\Android\sdk
• Android NDK location not configured (optional; useful for native profiling support)
• Platform android-29, build-tools 29.0.2
• Java binary at: C:\Program Files\Android\Android Studio\jre\bin\java
• Java version OpenJDK Runtime Environment (build 1.8.0_212-release-1586-b04)
• All Android licenses accepted.
[√] Android Studio (version 3.6)
• Android Studio at C:\Program Files\Android\Android Studio
• Flutter plugin version 44.0.2
• Dart plugin version 192.7761
• Java version OpenJDK Runtime Environment (build 1.8.0_212-release-1586-b04)
[√] IntelliJ IDEA Community Edition (version 2019.3)
• IntelliJ at C:\Program Files\JetBrains\IntelliJ IDEA Community Edition 2019.1.3
• Flutter plugin version 44.0.3
• Dart plugin version 193.6911.31
[√] VS Code (version 1.43.1)
• VS Code at C:\Users\Momshad\AppData\Local\Programs\Microsoft VS Code
• Flutter extension version 3.8.1
[√] Connected device (1 available)
• POCOPHONE F1 • 9ea76ae • android-arm64 • Android 10 (API 29)
• No issues found!
C:\src\flutter\bin\flutter.bat --no-color packages get
Running "flutter pub get" in App... 1.6s
Process finished with exit code 0
C:\src\flutter\bin\flutter.bat --no-color packages upgrade
Running "flutter pub upgrade" in App... 13.3s
Process finished with exit code 0
Launching lib\main.dart on POCOPHONE F1 in debug mode...
Compiler message:
lib/initialize.dart:2:8: Error: Not found: 'dart:html'
import 'dart:html';
^
/C:/src/flutter/.pub-cache/hosted/pub.flutter-io.cn/http-0.12.0+4/lib/src/browser_client.dart:6:8: Error: Not found: 'dart:html'
import 'dart:html';
^
/C:/src/flutter/.pub-cache/hosted/pub.flutter-io.cn/http-0.12.0+4/lib/src/browser_client.dart:34:18: Error: 'HttpRequest' isn't a type.
final _xhrs = <HttpRequest>{};
^^^^^^^^^^^
/C:/src/flutter/packages/flutter/lib/src/painting/_network_image_web.dart:64:12: Error: Method not found: 'webOnlyInstantiateImageCodecFromUrl'.
return ui.webOnlyInstantiateImageCodecFromUrl(resolved); // ignore: undefined_function
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
/C:/src/flutter/.pub-cache/hosted/pub.flutter-io.cn/http-0.12.0+4/lib/src/browser_client.dart:58:34: Error: 'Blob' isn't a type.
var blob = xhr.response as Blob ?? Blob([]);
^^^^
/C:/src/flutter/.pub-cache/hosted/pub.flutter-io.cn/http-0.12.0+4/lib/src/browser_client.dart:46:15: Error: The method 'HttpRequest' isn't defined for the class 'BrowserClient'.
- 'BrowserClient' is from 'package:http/src/browser_client.dart' ('/C:/src/flutter/.pub-cache/hosted/pub.flutter-io.cn/http-0.12.0+4/lib/src/browser_client.dart').
Try correcting the name to the name of an existing method, or defining a method named 'HttpRequest'.
var xhr = HttpRequest();
^^^^^^^^^^^
/C:/src/flutter/.pub-cache/hosted/pub.flutter-io.cn/http-0.12.0+4/lib/src/browser_client.dart:58:42: Error: The method 'Blob' isn't defined for the class 'BrowserClient'.
- 'BrowserClient' is from 'package:http/src/browser_client.dart' ('/C:/src/flutter/.pub-cache/hosted/pub.flutter-io.cn/http-0.12.0+4/lib/src/browser_client.dart').
最佳答案
删除dart:html可解决一些错误。但是我发现了问题。整个 Dart 环境都损坏了。遇到此服务器问题,在运行升级时,文件已损坏。结果,我遇到了那些错误。完全卸载所有内容后再重新安装即可解决。感谢大家
关于flutter - Flutter函数颜色未定义或未定义类颜色,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/60918872/
C语言sscanf()函数:从字符串中读取指定格式的数据 头文件: ?
最近,我有一个关于工作预评估的问题,即使查询了每个功能的工作原理,我也不知道如何解决。这是一个伪代码。 下面是一个名为foo()的函数,该函数将被传递一个值并返回一个值。如果将以下值传递给foo函数,
CStr 函数 返回表达式,该表达式已被转换为 String 子类型的 Variant。 CStr(expression) expression 参数是任意有效的表达式。 说明 通常,可以
CSng 函数 返回表达式,该表达式已被转换为 Single 子类型的 Variant。 CSng(expression) expression 参数是任意有效的表达式。 说明 通常,可
CreateObject 函数 创建并返回对 Automation 对象的引用。 CreateObject(servername.typename [, location]) 参数 serv
Cos 函数 返回某个角的余弦值。 Cos(number) number 参数可以是任何将某个角表示为弧度的有效数值表达式。 说明 Cos 函数取某个角并返回直角三角形两边的比值。此比值是
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CInt 函数 返回表达式,此表达式已被转换为 Integer 子类型的 Variant。 CInt(expression) expression 参数是任意有效的表达式。 说明 通常,可
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CDbl 函数 返回表达式,此表达式已被转换为 Double 子类型的 Variant。 CDbl(expression) expression 参数是任意有效的表达式。 说明 通常,您可
CDate 函数 返回表达式,此表达式已被转换为 Date 子类型的 Variant。 CDate(date) date 参数是任意有效的日期表达式。 说明 IsDate 函数用于判断 d
CCur 函数 返回表达式,此表达式已被转换为 Currency 子类型的 Variant。 CCur(expression) expression 参数是任意有效的表达式。 说明 通常,
CByte 函数 返回表达式,此表达式已被转换为 Byte 子类型的 Variant。 CByte(expression) expression 参数是任意有效的表达式。 说明 通常,可以
CBool 函数 返回表达式,此表达式已转换为 Boolean 子类型的 Variant。 CBool(expression) expression 是任意有效的表达式。 说明 如果 ex
Atn 函数 返回数值的反正切值。 Atn(number) number 参数可以是任意有效的数值表达式。 说明 Atn 函数计算直角三角形两个边的比值 (number) 并返回对应角的弧
Asc 函数 返回与字符串的第一个字母对应的 ANSI 字符代码。 Asc(string) string 参数是任意有效的字符串表达式。如果 string 参数未包含字符,则将发生运行时错误。
Array 函数 返回包含数组的 Variant。 Array(arglist) arglist 参数是赋给包含在 Variant 中的数组元素的值的列表(用逗号分隔)。如果没有指定此参数,则
Abs 函数 返回数字的绝对值。 Abs(number) number 参数可以是任意有效的数值表达式。如果 number 包含 Null,则返回 Null;如果是未初始化变量,则返回 0。
FormatPercent 函数 返回表达式,此表达式已被格式化为尾随有 % 符号的百分比(乘以 100 )。 FormatPercent(expression[,NumDigitsAfterD
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