The current Dart SDK version is 2.1.0-dev.1.0.flutter-69fce633b7.

Running "flutter packages get" in flutter_app...            
The current Dart SDK version is 2.1.0-dev.1.0.flutter-69fce633b7.

Because xxxx 0.0.16 requires SDK version <2.0.0 ..........

解决办法：其中uhf上文中xxx，也就是报错的三方包，就和

dev_dependencies 中一样的使用方式

dependency_overrides:
  uhf:
    path: flutter_uhf/