编译运行错误：
E/AndroidRuntime: FATAL EXCEPTION: mainProcess: com.onemore.littleapple.onemore, PID: 11598java.lang.NullPointerException: Attempt to invoke virtual method 'int java.lang.Integer.intValue()' on a null object referenceat com.onemore.littleapple.onemore.Adapter.ActionGroupAdapter$4.onClick(ActionGroupAdapter.java:133)at android.view.View.performClick(View.java:7333)at android.view.View.performClickInternal(View.java:7299)at android.view.View.access$3200(View.java:846)at android.view.View$PerformClick.run(View.java:27773)at android.os.Handler.handleCallback(Handler.java:873)at android.os.Handler.dispatchMessage(Handler.java:99)at android.os.Looper.loop(Looper.java:214)at android.app.ActivityThread.main(ActivityThread.java:6990)at java.lang.reflect.Method.invoke(Native Method)at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:494)at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1445)
错误代码行：
viewHolder.finishCurrentGroupImage.setOnClickListener(new View.OnClickListener() {@SuppressLint("ResourceAsColor")@Overridepublic void onClick(View v) {((MainActivity) mContext).OnFinishClickListener(mPosition, (int) v.getTag());}
});
MainActivity.java中：
/*** @param mPosition 为第一层recycleview位置* @param tag 为第二层recycleview位置*/public void OnFinishClickListener(int mPosition, int tag) {Log.e("点击的是母项和子项",""+mPosition+","+tag);}
修改Adapter.java:（在上述适配器代码前添加如下一行，便解决空指针错误）
viewHolder.finishCurrentGroupImage.setTag(i);