Crash with Gridlayout

[pawan52tiwari]

Hi All,

I am getting below crash randomly when we render the leanback fragment

 java.lang.NullPointerException: Attempt to invoke virtual method 'boolean androidx.recyclerview.widget.RecyclerView$State.isPreLayout()' on a null object reference
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at androidx.leanback.widget.GridLayoutManager$2.addItem(GridLayoutManager.java:1704)
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at androidx.leanback.widget.SingleRow.prependVisibleItems(SingleRow.java:93)
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at androidx.leanback.widget.Grid.prependVisibleItems(Grid.java:371)
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at androidx.leanback.widget.GridLayoutManager.prependVisibleItems(GridLayoutManager.java:1940)
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at androidx.leanback.widget.GridLayoutManager.scrollDirectionPrimary(GridLayoutManager.java:2455)
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at androidx.leanback.widget.GridLayoutManager.scrollVerticallyBy(GridLayoutManager.java:2406)
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at androidx.recyclerview.widget.RecyclerView.scrollStep(RecyclerView.java:1972)
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at androidx.recyclerview.widget.RecyclerView$ViewFlinger.run(RecyclerView.java:5476)
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at android.view.Choreographer$CallbackRecord.run(Choreographer.java:781)
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at android.view.Choreographer.doCallbacks(Choreographer.java:592)
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at android.view.Choreographer.doFrame(Choreographer.java:559)
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:767)
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at android.os.Handler.handleCallback(Handler.java:739)
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at android.os.Handler.dispatchMessage(Handler.java:95)
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at android.os.Looper.loop(Looper.java:135)
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at android.app.ActivityThread.main(ActivityThread.java:5604)
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at java.lang.reflect.Method.invoke(Native Method)
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at java.lang.reflect.Method.invoke(Method.java:372)
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:984)
08-11 18:11:23.668 E/AndroidRuntime(16942): 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:779)

How to fix this

[IanGClifton]

Are you seeing this bug with one of the samples in this repository or in your own project? If it's your own project using Leanback, you can file it via https://issuetracker.google.com/components/460758. If it's with one of these samples, please share which sample and repro steps.