Flutter 为 Web 构建 - "Failed to compile application"

Question

我已经为我的项目启用了 Web 支持，并且在运行后 flutter run -d chrome我收到以下错误:

Launching lib/main.dart on Chrome in debug mode...
Syncing files to device Chrome...                                                                                                                                                                    
Compiler message:                                  
../../flutter/.pub-cache/hosted/pub.dartlang.org/google_sign_in_web-0.8.3+1/lib/src/generated/gapiauth2.dart:26:3: Error: JS interop classes do not support non-external constructors.
Try annotating with `external`.                                                                                    
  GoogleAuth.fakeConstructor$();                                                                                   
  ^                                                                                                                
../../flutter/.pub-cache/hosted/pub.dartlang.org/google_sign_in_web-0.8.3+1/lib/src/generated/gapiauth2.dart:216:3: Error: JS interop classes do not support non-external constructors.
Try annotating with `external`.                                                                                    
  SigninOptionsBuilder.fakeConstructor$();                                                                         
  ^                                                                                                                
../../flutter/.pub-cache/hosted/pub.dartlang.org/google_sign_in_web-0.8.3+1/lib/src/generated/gapi.dart:351:3: Error: JS interop classes do not support non-external constructors.
Try annotating with `external`.                                                                                    
  HttpRequestPromise.fakeConstructor$();                                                                           
  ^                                                                                                                
../../flutter/.pub-cache/hosted/pub.dartlang.org/google_sign_in_web-0.8.3+1/lib/src/generated/gapi.dart:378:3: Error: JS interop classes do not support non-external constructors.
Try annotating with `external`.                                                                                    
  HttpRequest.fakeConstructor$() : super.fakeConstructor$();                                                       
  ^                                                                                                                
../../flutter/.pub-cache/hosted/pub.dartlang.org/google_sign_in_web-0.8.3+1/lib/src/generated/gapi.dart:402:3: Error: JS interop classes do not support non-external constructors.
Try annotating with `external`.                                                                                    
  HttpBatch.fakeConstructor$();                                                                                    
  ^                                                                                                                
../../flutter/.pub-cache/hosted/pub.dartlang.org/google_sign_in_web-0.8.3+1/lib/src/generated/gapi.dart:440:3: Error: JS interop classes do not support non-external constructors.
Try annotating with `external`.                                                                                    
  RpcRequest.fakeConstructor$();                                                                                   
  ^                                                                                                                
Syncing files to device Chrome...                               19,442ms (!)                                       
Failed to compile application.
Tals-Macbook:matkonit talbarda$ flutter run -d chrome
Launching lib/main.dart on Chrome in debug mode...
Syncing files to device Chrome...                                                                                                                                                                    
Compiler message:                                  
../../flutter/.pub-cache/hosted/pub.dartlang.org/google_sign_in_web-0.8.3+1/lib/src/generated/gapiauth2.dart:26:3: Error: JS interop classes do not support non-external constructors.
Try annotating with `external`.                                                                                    
  GoogleAuth.fakeConstructor$();                                                                                   
  ^                                                                                                                
../../flutter/.pub-cache/hosted/pub.dartlang.org/google_sign_in_web-0.8.3+1/lib/src/generated/gapiauth2.dart:216:3: Error: JS interop classes do not support non-external constructors.
Try annotating with `external`.                                                                                    
  SigninOptionsBuilder.fakeConstructor$();                                                                         
  ^                                                                                                                
../../flutter/.pub-cache/hosted/pub.dartlang.org/google_sign_in_web-0.8.3+1/lib/src/generated/gapi.dart:351:3: Error: JS interop classes do not support non-external constructors.
Try annotating with `external`.                                                                                    
  HttpRequestPromise.fakeConstructor$();                                                                           
  ^                                                                                                                
../../flutter/.pub-cache/hosted/pub.dartlang.org/google_sign_in_web-0.8.3+1/lib/src/generated/gapi.dart:378:3: Error: JS interop classes do not support non-external constructors.
Try annotating with `external`.                                                                                    
  HttpRequest.fakeConstructor$() : super.fakeConstructor$();                                                       
  ^                                                                                                                
../../flutter/.pub-cache/hosted/pub.dartlang.org/google_sign_in_web-0.8.3+1/lib/src/generated/gapi.dart:402:3: Error: JS interop classes do not support non-external constructors.
Try annotating with `external`.                                                                                    
  HttpBatch.fakeConstructor$();                                                                                    
  ^                                                                                                                
../../flutter/.pub-cache/hosted/pub.dartlang.org/google_sign_in_web-0.8.3+1/lib/src/generated/gapi.dart:440:3: Error: JS interop classes do not support non-external constructors.
Try annotating with `external`.                                                                                    
  RpcRequest.fakeConstructor$();                                                                                   
  ^                                                                                                                
Syncing files to device Chrome...                               17,899ms (!)                                       
Failed to compile application.

我怎样才能解决这个问题？

Answer 1

我注意到这个问题已在 google_sign_in_web 0.9.0 中修复。因此，请更改 pubspec.yaml 文件中的版本。

google_sign_in_web: ^0.9.1

2020 年 4 月 20 日更新:如果您依赖 google_sign_in，请在 pubspec.yaml 文件中更改该版本。

google_sign_in: 4.4.3

前:
但是，当你像我一样并且依赖于 google_sign_in 时，那么你还有更多的东西需要改变......
如果您将 google_sign_in_web 更改为 0.9.0，并将 google_sign_in 的版本更改为 4.4.1，则检索包将失败:

Because ${your_project_name} depends on google_sign_in 4.4.1 which depends on google_sign_in_web ^0.8.2, google_sign_in_web ^0.8.2 is required.
So, because ${your_project_name} depends on google_sign_in_web ^0.9.0, version solving failed.
pub get failed (1; So, because  ${your_project_name} depends on google_sign_in_web ^0.9.0, version solving failed.)

在这种情况下，您必须等待 google_sign_in 升级(我创建了拉取请求 https://github.com/flutter/plugins/pull/2647 )，或者暂时像我一样:

1) 从 https://github.com/flutter/plugins 克隆 flutter 插件

mkdir /src
cd /src
git clone https://github.com/flutter/plugins.git

2) 更改/src/plugins/plugins/packages/google_sign_in/google_sign_in/pubspec.yaml 中的文件 pubspec.yaml

  google_sign_in_web: ^0.9.0

3) 更改项目中的依赖项以指向更改后的 google_sign_in 版本，即

google_sign_in:
  path: ../../flutter/plugins/packages/google_sign_in/google_sign_in
google_sign_in_web: ^0.9.0