NPE on RecyclerAdapter#getItemCount

[hybd666]

Exception
App Name: Amaze File Manager
Version: 3.10
User Action: UI Error
Request: Application crash
OS: Linux Android 11 - 30
Device: Google Nexus 4

crash log

java.lang.RuntimeException: Unable to destroy activity {com.amaze.filemanager.debug/com.amaze.filemanager.ui.activities.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'int java.util.ArrayList.size()' on a null object reference
at android.app.ActivityThread.performDestroyActivity(ActivityThread.java:5111)
at android.app.ActivityThread.handleDestroyActivity(ActivityThread.java:5140)
at android.app.ActivityThread.handleRelaunchActivityInner(ActivityThread.java:5432)
at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:5362)
at android.app.servertransaction.ActivityRelaunchItem.execute(ActivityRelaunchItem.java:69)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2066)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:223)
at android.app.ActivityThread.main(ActivityThread.java:7656)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)

Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'int java.util.ArrayList.size()' on a null object reference
at com.amaze.filemanager.adapters.RecyclerAdapter.getItemCount(RecyclerAdapter.java:686)
at com.amaze.filemanager.ui.views.FastScroller.invalidateVisibility(FastScroller.java:158)
at com.amaze.filemanager.ui.views.FastScroller.-$$Nest$minvalidateVisibility(Unknown Source:0)
at com.amaze.filemanager.ui.views.FastScroller$1.onChildViewRemoved(FastScroller.java:237)
at android.view.ViewGroup.dispatchViewRemoved(ViewGroup.java:5136)
at android.view.ViewGroup.removeViewInternal(ViewGroup.java:5585)
at android.view.ViewGroup.removeViewAt(ViewGroup.java:5507)
at androidx.recyclerview.widget.RecyclerView$5.removeViewAt(RecyclerView.java:882)
at androidx.recyclerview.widget.ChildHelper.removeViewIfHidden(ChildHelper.java:386)
at androidx.recyclerview.widget.RecyclerView.removeAnimatingView(RecyclerView.java:1452)
at androidx.recyclerview.widget.RecyclerView$ItemAnimatorRestoreListener.onAnimationFinished(RecyclerView.java:12699)
at androidx.recyclerview.widget.RecyclerView$ItemAnimator.dispatchAnimationFinished(RecyclerView.java:13199)
at androidx.recyclerview.widget.SimpleItemAnimator.dispatchChangeFinished(SimpleItemAnimator.java:317)
at androidx.recyclerview.widget.DefaultItemAnimator$7.onAnimationEnd(DefaultItemAnimator.java:370)
at android.view.ViewPropertyAnimator$AnimatorEventListener.onAnimationEnd(ViewPropertyAnimator.java:1111)
at android.animation.Animator$AnimatorListener.onAnimationEnd(Animator.java:554)
at android.animation.ValueAnimator.endAnimation(ValueAnimator.java:1250)
at android.animation.ValueAnimator.cancel(ValueAnimator.java:1135)
at android.view.ViewPropertyAnimator.cancel(ViewPropertyAnimator.java:424)
at androidx.recyclerview.widget.DefaultItemAnimator.cancelAll(DefaultItemAnimator.java:642)
at androidx.recyclerview.widget.DefaultItemAnimator.endAnimations(DefaultItemAnimator.java:635)
at androidx.recyclerview.widget.RecyclerView.onDetachedFromWindow(RecyclerView.java:2996)
at android.view.View.dispatchDetachedFromWindow(View.java:20534)
at android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:3942)
at android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:3934)
at android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:3934)
at android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:3934)
at android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:3934)
at android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:3934)
at android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:3934)
at android.view.ViewGroup.removeViewInternal(ViewGroup.java:5560)
at android.view.ViewGroup.removeViewInternal(ViewGroup.java:5531)
at android.view.ViewGroup.removeView(ViewGroup.java:5462)
at androidx.fragment.app.SpecialEffectsController$Operation$State.applyState(SpecialEffectsController.java:470)
at androidx.fragment.app.SpecialEffectsController$1.run(SpecialEffectsController.java:211)
at androidx.fragment.app.SpecialEffectsController$Operation.complete(SpecialEffectsController.java:713)
at androidx.fragment.app.SpecialEffectsController$FragmentStateManagerOperation.complete(SpecialEffectsController.java:770)
at androidx.fragment.app.SpecialEffectsController$Operation.cancel(SpecialEffectsController.java:615)
at androidx.fragment.app.SpecialEffectsController.forceCompleteAllOperations(SpecialEffectsController.java:350)
at androidx.fragment.app.FragmentManager.dispatchStateChange(FragmentManager.java:2982)
at androidx.fragment.app.FragmentManager.dispatchDestroy(FragmentManager.java:2933)
at androidx.fragment.app.FragmentController.dispatchDestroy(FragmentController.java:346)
at androidx.fragment.app.FragmentActivity.onDestroy(FragmentActivity.java:259)
at androidx.appcompat.app.AppCompatActivity.onDestroy(AppCompatActivity.java:283)
at com.amaze.filemanager.ui.activities.superclasses.ThemedActivity.onDestroy(ThemedActivity.java:348)
at com.amaze.filemanager.ui.activities.MainActivity.onDestroy(MainActivity.java:1462)
at android.app.Activity.performDestroy(Activity.java:8239)
at android.app.Instrumentation.callActivityOnDestroy(Instrumentation.java:1344)
at android.app.ActivityThread.performDestroyActivity(ActivityThread.java:5096)
... 13 more