Crash in androidx.appcompat.app.AppCompatDelegateImpl.createSubDecor

[ewoerner]

Exception java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
  at androidx.appcompat.app.AppCompatDelegateImpl.createSubDecor (AppCompatDelegateImpl.java:926)
  at androidx.appcompat.app.AppCompatDelegateImpl.ensureSubDecor (AppCompatDelegateImpl.java:889)
  at androidx.appcompat.app.AppCompatDelegateImpl.onPostCreate (AppCompatDelegateImpl.java:585)
  at androidx.appcompat.app.AppCompatActivity.onPostCreate (AppCompatActivity.java:153)
  at android.app.Instrumentation.callActivityOnPostCreate (Instrumentation.java:1491)
  at android.app.ActivityThread.handleStartActivity (ActivityThread.java:3696)
  at android.app.servertransaction.TransactionExecutor.performLifecycleSequence (TransactionExecutor.java:224)
  at android.app.servertransaction.TransactionExecutor.cycleToPath (TransactionExecutor.java:204)
  at android.app.servertransaction.TransactionExecutor.executeLifecycleState (TransactionExecutor.java:176)
  at android.app.servertransaction.TransactionExecutor.execute (TransactionExecutor.java:97)
  at android.app.ActivityThread$H.handleMessage (ActivityThread.java:2306)
  at android.os.Handler.dispatchMessage (Handler.java:106)
  at android.os.Looper.loopOnce (Looper.java:201)
  at android.os.Looper.loop (Looper.java:288)
  at android.app.ActivityThread.main (ActivityThread.java:7918)
  at java.lang.reflect.Method.invoke
  at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run (RuntimeInit.java:548)
  at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:936)