渡槽:如何解决不良状态:无元素错误

Question

在Getting Started with Aqueduct上按照步骤创建渡槽的新项目时，我在创建新项目时遇到错误

错误：

C:\Users\khalifa>aqueduct create store1
-- Aqueduct CLI Version: 3.3.0+1
*** Uncaught error
    Bad state: No element
  **** Stacktrace
  * #0      ListMixin.firstWhere (dart:collection/list.dart:150:5)
  * #1      CLIAqueductGlobal.aqueductPackageRef (package:aqueduct/src/cli/commands/create.dart:342:10)
  * #2      CLIAqueductGlobal.templateDirectory (package:aqueduct/src/cli/commands/create.dart:347:12)
  * #3      CLIAqueductGlobal.getTemplateLocation (package:aqueduct/src/cli/commands/create.dart:351:12)
  * #4      CLITemplateCreator.handle (package:aqueduct/src/cli/commands/create.dart:51:27)
  * #5      CLICommand.process (package:aqueduct/src/cli/command.dart:159:20)
  * <asynchronous suspension>
  * #6      CLICommand.process (package:aqueduct/src/cli/command.dart:135:12)
  * #7      main (file:///C:/Users/khalifa/AppData/Local/Pub/Cache/hosted/pub.dartlang.org/aqueduct-3.3.0+1/bin/aqueduct.dart:9:27)
  * #8      _startIsolate.<anonymous closure> (dart:isolate-patch/isolate_patch.dart:299:32)
  * #9      _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:168:12)
  ****

dart的版本为：

Dart VM version: 2.8.4 (stable) (Wed Jun 3 12:26:04 2020 +0200) on "windows_x64"

Answer 1

我很确定你还没做过pub global activate aqueduct

stackTrace指向342行

   341 .getGlobalApplications()
   342 .firstWhere((app) => app.name == "aqueduct")

当Iterable中没有元素时，firstWhere()抛出StateError("No element")