                        課程
                    
                        /移動開發
                        
                            /Android
                        
                        /ReactNative入門與進階

react-native run-android報錯，求助

D:\project\React\React?Native\FirstApp>react-native?run-android
Scanning?folders?for?symlinks?in?D:\project\React\React?Native\FirstApp\node_modules?(21ms)
Starting?JS?server...
Building?and?installing?the?app?on?the?device?(cd?android?&&?gradlew.bat?installDebug)...
錯誤:?找不到或無法加載主類?org.gradle.wrapper.GradleWrapperMain
Could?not?install?the?app?on?the?device,?read?the?error?above?for?details.
Make?sure?you?have?an?Android?emulator?running?or?a?device?connected?and?have
set?up?your?Android?development?environment:
https://facebook.github.io/react-native/docs/android-setup.html

模擬器已開，問下大家這個問題怎么解決