Android Question Howto find and fix exception "WeakReference.get()' on a null object reference"

[fredo]

FireBase Crash Reporting showed this:

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Spoiler: Message as text

 Exception java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.Object java.lang.ref.WeakReference.get()' on a null object reference

anywheresoftware.b4a.Msgbox$DialogResponse.onClick (Msgbox.java:147)
com.android.internal.app.AlertController$AlertParams$3.onItemClick (AlertController.java:1228)
android.widget.AdapterView.performItemClick (AdapterView.java:346)
android.widget.AbsListView.performItemClick (AbsListView.java:1550)
android.widget.AbsListView$PerformClick.run (AbsListView.java:3830)
android.widget.AbsListView$3.run (AbsListView.java:5855)
android.os.Handler.handleCallback (Handler.java:739)
android.os.Handler.dispatchMessage (Handler.java:95)
android.os.Looper.loop (Looper.java:148)
android.app.ActivityThread.main (ActivityThread.java:7325)
java.lang.reflect.Method.invoke (Method.java)
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run (ZygoteInit.java:1230)
com.android.internal.os.ZygoteInit.main (ZygoteInit.java:1120)

Normally we would search the stacktrace for a line that refers to a file in \..\src\*.java so the corresponding line in the project file could be found. But there is no clue where to look for the problem...

What would be the best approach to fix this?​

The last changes made in the project were only minor changes due to bugfixes. B4A V 7.01 was used to compile.

 

[Erel]

Are you using InputList in your program?
Based on the error the click event somehow fired after it was dismissed.

It is better to switch to InputListAsync.

 

[fredo]

Are you using InputList in your program?

Yes, 53 times.

...better to switch to InputListAsync.

Thank you for the hint. Will do so and report later if the error doesn't rise in Firebase Crashreports anymore.