Could not find method flatDir()

[divyong]

Hi, i have a problem with installation

I followed the installation tutorial and got an error:

$ react-native run-android
info Starting JS server...
info Building and installing the app on the device (cd android && ./gradlew app:installDebug)...

FAILURE: Build failed with an exception.

* Where:
Build file '/home/dinakh/coding/heatmaps/android/build.gradle' line: 38

* What went wrong:
A problem occurred evaluating root project 'heatmaps'.
> Could not find method flatDir() for arguments [build_16li6tpgxnj2j0te3pa44mvok$_run_closure2@76db3fd5] on root project 'heatmaps' of type org.gradle.api.Project.

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 0s
error 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/getting-started.html
error Command failed: ./gradlew app:installDebug. Run CLI with --verbose flag for more details.

How can i fix it?
If you help me it would be awesome