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Android Android Lists and Adapters Adapters and ViewHolders Activity

Posted by aaronr
aaronr
2,493 Points

NullPointerException at holder.hourlyListItemBinding.setHour(hour);

I'm stuck I get the following error below when debugging. I don't have a good understanding of the RecyclerView which makes troubleshooting very difficult. I'm not sure where to even start.

E/AndroidRuntime: FATAL EXCEPTION: main Process: com.example.stormy, PID: 11296 java.lang.NullPointerException: Attempt to invoke virtual method 'void com.example.stormy.databinding.HourlyListItemBinding.setHour(com.example.stormy.weather.Hour)' on a null object reference at com.example.stormy.adapters.HourlyAdapter.onBindViewHolder(HourlyAdapter.java:43) at com.example.stormy.adapters.HourlyAdapter.onBindViewHolder(HourlyAdapter.java:17) at androidx.recyclerview.widget.RecyclerView$Adapter.onBindViewHolder(RecyclerView.java:6781) at androidx.recyclerview.widget.RecyclerView$Adapter.bindViewHolder(RecyclerView.java:6823) at androidx.recyclerview.widget.RecyclerView$Recycler.tryBindViewHolderByDeadline(RecyclerView.java:5752) at androidx.recyclerview.widget.RecyclerView$Recycler.tryGetViewHolderForPositionByDeadline(RecyclerView.java:6019) at androidx.recyclerview.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:5858) at androidx.recyclerview.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:5854) at androidx.recyclerview.widget.LinearLayoutManager$LayoutState.next(LinearLayoutManager.java:2230) at androidx.recyclerview.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1557) at androidx.recyclerview.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1517) at androidx.recyclerview.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.java:612) at androidx.recyclerview.widget.RecyclerView.dispatchLayoutStep2(RecyclerView.java:3924) at androidx.recyclerview.widget.RecyclerView.dispatchLayout(RecyclerView.java:3641) at androidx.recyclerview.widget.RecyclerView.onLayout(RecyclerView.java:4194) at android.view.View.layout(View.java:22740) at android.view.ViewGroup.layout(ViewGroup.java:6291) at androidx.constraintlayout.widget.ConstraintLayout.onLayout(ConstraintLayout.java:1915) at android.view.View.layout(View.java:22740) at android.view.ViewGroup.layout(ViewGroup.java:6291) at android.widget.FrameLayout.layoutChildren(FrameLayout.java:332) at android.widget.FrameLayout.onLayout(FrameLayout.java:270) at android.view.View.layout(View.java:22740) at android.view.ViewGroup.layout(ViewGroup.java:6291) at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1829) at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1673) at android.widget.LinearLayout.onLayout(LinearLayout.java:1582) at android.view.View.layout(View.java:22740) at android.view.ViewGroup.layout(ViewGroup.java:6291) at android.widget.FrameLayout.layoutChildren(FrameLayout.java:332) at android.widget.FrameLayout.onLayout(FrameLayout.java:270) at android.view.View.layout(View.java:22740) at android.view.ViewGroup.layout(ViewGroup.java:6291) at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1829) at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1673) at android.widget.LinearLayout.onLayout(LinearLayout.java:1582) at android.view.View.layout(View.java:22740) at android.view.ViewGroup.layout(ViewGroup.java:6291) at android.widget.FrameLayout.layoutChildren(FrameLayout.java:332) at android.widget.FrameLayout.onLayout(FrameLayout.java:270) at com.android.internal.policy.DecorView.onLayout(DecorView.java:776) at android.view.View.layout(View.java:22740) at android.view.ViewGroup.layout(ViewGroup.java:6291) at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:3402) at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2879) at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1906) at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:8089) at android.view.Choreographer$CallbackRecord.run(Choreographer.java:972) at android.view.Choreographer.doCallbacks(Choreographer.java:796) at android.view.Choreographer.doFrame(Choreographer.java:731) at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:957) at android.os.Handler.handleCallback(Handler.java:907) E/AndroidRuntime: at android.os.Handler.dispatchMessage(Handler.java:99) at android.os.Looper.loop(Looper.java:223) at android.app.ActivityThread.main(ActivityThread.java:7478) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:549) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:941)