react-native run-android报错，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)... 错误: 找不到或无法加载主类 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
模拟器已开，问下大家这个问题怎么解决
