报错Fatal Exception: java.lang.IllegalStateException: The specified child already has a parent.

前段时间发现线上报了这个错，去看日志就这么点东西，可算是折腾我啊 

Fatal Exception: java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
       at android.view.ViewGroup.addViewInner(ViewGroup.java:5122)
       at android.view.ViewGroup.addView(ViewGroup.java:4953)
       at android.view.ViewGroup.addView(ViewGroup.java:4893)
       at android.view.ViewGroup.addView(ViewGroup.java:4866)
       at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1434)
       at android.support.v4.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManager.java:1759)
       at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1827)
       at android.support.v4.app.BackStackRecord.executePopOps(BackStackRecord.java:855)
       at android.support.v4.app.FragmentManagerImpl.executeOps(FragmentManager.java:2593)
       at android.support.v4.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2383)
       at android.support.v4.app.FragmentManagerImpl.removeRedundantOperationsAndExecute(FragmentManager.java:2338)
       at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:2245)
       at android.support.v4.app.FragmentManagerImpl$1.run(FragmentManager.java:703)
       at android.os.Handler.handleCallback(Handler.java:789)
       at android.os.Handler.dispatchMessage(Handler.java:98)
       at android.os.Looper.loop(Looper.java:164)
       at android.app.ActivityThread.main(ActivityThread.java:6940)
       at java.lang.reflect.Method.invoke(Method.java)
       at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:327)
       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1374)

没办法，只好去分析源码

看报错信息的意思是f.mView有属于它的父view，刚看到这可懵了，这是FragmentManager的源码，我可怎么改，最后继续分析下去，来看看f.mView是怎么来的，它是performCreateView方法的返回值，于是就走进去看看

进去一看不要紧，原来它是onCreateView方法的返回值，总算是看到曙光了啊

于是就有了接下来两个解决方案：

方案一

方案二：是把上面删除的代码加到onDestroyView中

以上方法经测都有效，特此记录一下，留作备用！