Flutter之导url_launcher包提示 A dependency may only have one source.

1、问题

flutter项目在pubspec.yaml导入url_launcher包，然后点击Pub get错误提示如下

F:\flutter_sdk\flutter\bin\flutter.bat --no-color pub get
Running "flutter pub get" in flutter_1...
Error on line 25, column 5 of pubspec.yaml: A dependency may only have one source.

   ╷

25 │ ┌     sdk: flutter

26 │ │     url_launcher: ^5.5.0

27 │ │ 

28 │ │ 

29 │ │   # The following adds the Cupertino Icons font to your application.

30 │ │   # Use with the CupertinoIcons class for iOS style icons.

31 │ │   cupertino_icons: ^0.1.3

   │ └──^

   ╵
pub get failed (65;    ╵)
Process finished with exit code 65

2、分析

cupertino_icons和url_launcher关键字没有左对齐

3、解决办法

让cupertino_icons和url_launcher关键字左对齐，然后再点击Pub get更新包就行