Execution failed for task ':app:checkDebugDuplicateClasses'. Ionic4 Android

Question

I\'m currently working on an ionic4 application, but recently it stopped working while building the application on an android reall device after adding https://ionicframewor

Answer 1

Your project (or one of its sub-projects) is referring to a dependency using the + plus-sign at its end, like com.google.firebase:firebase-auth:+, which means, use any higher version when possible, and that newer version is no longer using android.support libraries and instead is using androidx; to fix this issue follow the below steps.

Steps:

1. Ensure the ANDROID_HOME environment-variable is set, and then, open a console window (like git-bash, because it keeps the whole command output), and cd into your android directory (for Ionic projects it should be platforms/android).
2. First, List all dependencies by running below (in git-bash):

   ./gradlew :app:dependencies
   

3. Copy the result into your preferred text-editor, and search for androidx.
4. If you found something follow below steps, else you are done! (and you do not need to repeat these steps).
5. Scroll up until you see -> at the end of any line, like for example 16.0.8 -> 19.0.0 or + -> 19.0.0, which both mean that the version was auto-resolved (to something higher than specified by you because of +).
6. So, set the version down manually:
   • When possible, in your project find and replace the + sign with a specific version.
   • Or, force a specific version of the dependencies like mentioned below.
7. At last, repeat above steps (but instead of step one just clear the console).

---

To Force specific version of the dependencies add to your root build.gradle something like below (which is what worked for me) but edit and add your own rules (if these do not work for you):

allprojects {
  // ...
  configurations.all {
    resolutionStrategy {
      force 'com.google.firebase:firebase-common:17.0.0'
      force 'com.google.android.gms:play-services-basement:16.2.0'
      force 'com.google.firebase:firebase-iid:16.0.0'
      force 'com.google.firebase:firebase-auth:17.0.0'
    }
  }
}