flutter提示pub get failed -Because demo requires SDK version >-2.19.2 <3.0.0, version solving failed错误

flutter提示pub get failed (1; Because demo requires SDK version >-2.19.2 <3.0.0, version solving failed.)exit code 1错误

Because demo requires SDK version >-2.19.2 <3.0.0, version solving failed.pub get failed (1; Because demo requires SDK version >-2.19.2 <3.0.0, version solving failed.)

如下图：

解决方法

1、重新下载安装dart sdk

2、打开android studio 重新安装dart flutter sdk插件

3、一定要新建项目，不要运行老项目

4、运行老项目的方法： 1、新建项目确保可以运行 2、复制老项目的lib到新项目 3、安装老项目里面的依赖