Ionic android build failing 'CordovaLib'

Question

I've searched everywhere and there's no info regarding this error. I have android studio, tried several sdk's, same error. The environment variables have also been set up properly.

This is line 40 of build.gradle btw, apply plugin: 'com.android.library'

FAILURE: Build failed with an exception.

• Where: Build file '/home/user/Documents/app/platforms/android/CordovaLib/build.gradle' line: 40

A problem occurred evaluating project ':CordovaLib'.
org.gradle.api.Project.getPluginManager()Lorg/gradle/api/plugins/PluginManager;

Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.
        at ChildProcess.whenDone (/home/user/app/platforms/android/cordova/node_modules/cordova-common/src/superspawn.js:169:23)
        at ChildProcess.emit (events.js:182:13)
        at maybeClose (internal/child_process.js:947:16)
        at Process.ChildProcess._handle.onexit (internal/child_process.js:236:5)
    (node:2259) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1)
    (node:2259) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

Answer 1

For those of you getting this error, it has to do with your gradle configuration. I've installed gradle through package manager and it installed an old version, which I asumed it was fine. At least v4.1 of gradle is required to work properly with the latest cordova and android.

Make sure you install the newest gradle from their website: https://gradle.org/install/#manually

Set your gradle PATH properly: $ export PATH=$PATH:/gradle_install_loc/gradle-4.7/bin

Also make sure you're running the correct gradle version in your .properties and .gradle files in your project folder:

/app_name/platforms/android/gradle/wrapper/gradle-wrapper.properties