what is causing “cannot resolve symbol GradleException” in a flutter project?

Set Project SDK to Android API Platform version 29 (or the latest version, 30), like so:

defaultConfig {
    ...
    minSdkVersion 16
    targetSdkVersion 30
}

and update GradleException() to FileNotFoundException()

Please follow it:
https://github.com/flutter/flutter/issues/29608#issuecomment-548649907

This works for me, Thanks