Manifest merger failed : Attribute application@appComponentFactory

[Problem]

Manifest merger failed : Attribute application@appComponentFactory value=(androidx.core.app.CoreComponentFactory) from [androidx.core:core:1.0.0-alpha3] AndroidManifest.xml:22:18-86 is also present at [com.android.support:support-compat:28.0.0-alpha3] AndroidManifest.xml:22:18-91 value=(android.support.v4.app.CoreComponentFactory). Suggestion: add 'tools:replace="android:appComponentFactory"' to element at AndroidManifest.xml:6:5-40:19 to override.

 

[Solution]

Add this:

tools:replace="android:appComponentFactory"
android:appComponentFactory="whateverString"

to your manifest application

<application
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:roundIcon="@mipmap/ic_launcher_round"
    tools:replace="android:appComponentFactory"
    android:appComponentFactory="whateverString">

 

https://stackoverflow.com/questions/50782435/android-design-support-library-for-api-28-p-not-working

Android design support library for API 28 (P) not working