Java. lang. IllegalArgumentException: The observer is null. Final Solution, isnull

Java. lang. IllegalArgumentException: The observer is null. Final Solution, isnull
Java. lang. IllegalArgumentException: The observer is null. Final Solution

When using data adaptation:

java.lang.IllegalArgumentException: The observer is null.at android.database.Observable.unregisterObserver(Observable.java:64)at android.widget.BaseAdapter.unregisterDataSetObserver(BaseAdapter.java:42)at android.widget.AbsListView.onDetachedFromWindow(AbsListView.java:2872)at android.view.View.dispatchDetachedFromWindow(View.java:11908)at android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:2647)at android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:2645)at android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:2645)at android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:2645)at android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:2645)at android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:2645)at android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:2645)at android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:2645)at android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:2645)at android.view.ViewRootImpl.dispatchDetachedFromWindow(ViewRootImpl.java:2685)at android.view.ViewRootImpl.doDie(ViewRootImpl.java:4044)at android.view.ViewRootImpl.die(ViewRootImpl.java:4027)at android.view.WindowManagerImpl.removeViewImmediate(WindowManagerImpl.java:375)at android.view.WindowManagerImpl$CompatModeWrapper.removeViewImmediate(WindowManagerImpl.java:170)at android.app.ActivityThread.handleDestroyActivity(ActivityThread.java:3352)at android.app.ActivityThread.access$1200(ActivityThread.java:140)at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1266)at android.os.Handler.dispatchMessage(Handler.java:99)at android.os.Looper.loop(Looper.java:137)at android.app.ActivityThread.main(ActivityThread.java:4914)at java.lang.reflect.Method.invokeNative(Native Method)at java.lang.reflect.Method.invoke(Method.java:511)at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:808)at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:575)at dalvik.system.NativeStart.main(Native Method)

The cause is BaseAdapter.
Solution: add the following code when using the extends BaseAdapter:

@Overridepublic void unregisterDataSetObserver(DataSetObserver observer) {if (observer != null) {        super.unregisterDataSetObserver(observer);    }}

Hope to help you. Come on!

Here is also me: my eoe blog address for this question

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