Help debugging an Android crash

[TJ]

Hey all,

When I navigate to a new view my app crashes on Android with the following stack trace:

E/TNS.Native( 5898): Error: java.lang.NullPointerException: Attempt to invoke virtual method 'int android.view.View.getImportantForAccessibility()' on a null object reference
E/TNS.Native( 5898):     android.widget.AbsListView.obtainView(AbsListView.java:2360)
E/TNS.Native( 5898):     android.widget.ListView.makeAndAddView(ListView.java:1864)
E/TNS.Native( 5898):     android.widget.ListView.fillDown(ListView.java:698)
E/TNS.Native( 5898):     android.widget.ListView.fillFromTop(ListView.java:759)
E/TNS.Native( 5898):     android.widget.ListView.layoutChildren(ListView.java:1659)
E/TNS.Native( 5898):     android.widget.AbsListView.onLayout(AbsListView.java:2148)
E/TNS.Native( 5898):     android.view.View.layout(View.java:15596)
E/TNS.Native( 5898):     android.view.ViewGroup.layout(ViewGroup.java:4966)
E/TNS.Native( 5898):     com.tns.Platform.callJSMethodNative(Native Method)
E/TNS.Native( 5898):     com.tns.Platform.dispatchCallJSMethodNative(Platform.java:799)
E/TNS.Native( 5898):     com.tns.Platform.callJSMethod(Platform.java:644)
E/TNS.Native( 5898):     com.tns.Platform.callJSMethod(Platform.java:628)
E/TNS.Native( 5898):     com.tns.Platform.callJSMethod(Platform.java:618)
E/TNS.Native( 5898):     com.tns.android.view.ViewGroup.onLayout(ViewGroup.java:4515)
E/TNS.Native( 5898):     android.view.View.layout(View.java:15596)
E/TNS.Native( 5898):     android.view.ViewGroup.layout(ViewGroup.java:4966)
E/TNS.Native( 5898):     android.widget.FrameLayout.layoutChildren(FrameLayout.java:573)
E/TNS.Native( 5898):     android.widget.FrameLayout.onLayout(FrameLayout.java:508)
E/TNS.Native( 5898):     android.view.View.layout(View.java:15596)
E/TNS.Native( 5898):     android.view.ViewGroup.layout(ViewGroup.java:4966)
E/TNS.Native( 5898):     com.android.internal.widget.ActionBarOverlayLayout.onLayout(ActionBarOverlayLayout.java:494)
E/TNS.Native( 5898):     android.view.View.layout(View.java:15596)
E/TNS.Native( 5898):     android.view.ViewGroup.layout(ViewGroup.java:4966)
E/TNS.Native( 5898):     android.widget.FrameLayout.layoutChildren(FrameLayout.java:573)
E/TNS.Native( 5898):     android.widget.FrameLayout.onLayout(FrameLayout.java:508)
E/TNS.Native( 5898):     android.view.View.layout(View.java:15596)
E/TNS.Native( 5898):     android.view.ViewGroup.layout(ViewGroup.java:4966)
E/TNS.Native( 5898):     android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2072)
E/TNS.Native( 5898):     android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1829)
E/TNS.Native( 5898):     android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1054)
E/TNS.Native( 5898):     android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5779)
E/TNS.Native( 5898):     android.view.Choreographer$CallbackRecord.run(Choreographer.java:767)
E/TNS.Native( 5898):     android.view.Choreographer.doCallbacks(Choreographer.java:580)
E/TNS.Native( 5898):     android.view.Choreographer.doFrame(Choreographer.java:550)
E/TNS.Native( 5898):     android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:753)
E/TNS.Native( 5898):     android.os.Handler.handleCallback(Handler.java:739)
E/TNS.Native( 5898):     android.os.Handler.dispatchMessage(Handler.java:95)
E/TNS.Native( 5898):     android.os.Looper.loop(Looper.java:135)
E/TNS.Native( 5898):     android.app.ActivityThread.main(ActivityThread.java:5221)
E/TNS.Native( 5898):     java.lang.reflect.Method.invoke(Native Method)
E/TNS.Native( 5898):     java.lang.reflect.Method.invoke(Method.java:372)
E/TNS.Native( 5898):     com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
E/TNS.Native( 5898):     com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
E/TNS.Native( 5898): File: "ui/core/view, line: 133, column: 17
E/TNS.Native( 5898): StackTrace:
E/TNS.Native( 5898): Frame: function:'View._setBounds', file:'ui/core/view', line: 131, column: 18
E/TNS.Native( 5898): Frame: function:'LayoutInfo.arrange', file:'ui/core/layout', line: 115, column: 23
E/TNS.Native( 5898): Frame: function:'View.arrange', file:'ui/core/view-common', line: 252, column: 26
E/TNS.Native( 5898): Frame: function:'GridPanel._arrangeOverride', file:'ui/panels/grid-panel', line: 829, column: 30
E/TNS.Native( 5898): Frame: function:'LayoutInfo.arrangeCore', file:'ui/core/layout', line: 152, column: 19
E/TNS.Native( 5898): Frame: function:'LayoutInfo.arrange', file:'ui/core/layout', line: 108, column: 14
E/TNS.Native( 5898): Frame: function:'View.arrange', file:'ui/core/view-common', line: 252, column: 26
E/TNS.Native( 5898): Frame: function:'ContentView._arrangeOverride', file:'ui/content-view/content-view-common', line: 62, column: 26
E/TNS.Native( 5898): Frame: function:'LayoutInfo.arrangeCore', file:'ui/core/layout', line: 152, column: 19
E/TNS.Native( 5898): Frame: function:'LayoutInfo.arrange', file:'ui/core/layout', line: 108, column: 14
E/TNS.Native( 5898): Frame: function:'View.arrange', file:'ui/core/view-common', line: 252, column: 26
E/TNS.Native( 5898): Frame: function:'Frame._arrangeOverride', file:'ui/frame', line: 251, column: 30
E/TNS.Native( 5898): Frame: function:'LayoutInfo.arrangeCore', file:'ui/core/layout', line: 152, column: 19
E/TNS.Native( 5898): Frame: function:'LayoutInfo.arrange', file:'ui/core/layout', line: 108, column: 14
E/TNS.Native( 5898): Frame: function:'View.arrange', file:'ui/core/view-common', line: 252, column: 26
E/TNS.Native( 5898): Frame: function:'onLayoutNative', file:'utils/utils', line: 126, column: 24

I'm not sure what's up or how to debug this further. The app works fine on iOS. To recreate this you can clone this app (https://github.com/tjvantoll/groceries), run it on Android, and click the Sign in button. It crashes every time.

Any help would be appreciated.

Thanks,
TJ

[Vlad]

Hi TJ,

Can you remove temporary GridPanel and leave the ListView only to see what will be the result? 

Regards,
Vlad
Telerik

 

 

[TJ]

Hi Vlad,

I removed the GridPanel and I still got the same error. After playing with this a bit more it seems to be related to the data binding. Here's my page's XML: https://gist.github.com/tjvantoll/18b85404b79be60e7cff. If I remove the `items="{{groceries}}"` attribute from the ListView the app runs fine.

Unfortunately I'm not really sure how to debug this further because the same code runs fine on iOS and the stack trace doesn't give any hints as to what might be wrong.

TJ

[Vlad]

Hi TJ,

Unfortunately we are still unable to reproduce this error. I'll post here if we find what's causing this exception. 

Regards,
Vlad
Telerik