首先，android中的fragment是什么？
http://developer.android.com/guide/topics/fundamentals/fragments.html
场景：
现有两个fragment(e.g:loginfragment、homefragment)需要在android程序运行的时候进行动态加载、切换，这种情况下，比较容器出现的一个问题就是：
这里，贴出处理此问题的几个代码片段，备忘之：
main.xml
出现the specified child already has a parent. you must call removeview() on the child's parent first.这个问题，一般原因是对layout.xml的使用理解不清楚。
以xml文件方式来设计界面的布局，如果需要动态的对xml文件中的各类view进行修改的话，在代码中使用时，不能直接使用this.findviewbyid(r.id.***)来获取xml文件中的每个view，然后再将这些view加入到代码中的layout中来进行显示。正确的做法应该是使用inflater。
举例如下：
xml布局文件test.xml为：
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You must call removeView() on the child&#39;s parent first <?xml version="1.0" encoding="utf-8"?>
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You must call removeView() on the child&#39;s parent first <linearlayout xmlns:android="http://schemas.android.com/apk/res/android"
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You must call removeView() on the child&#39;s parent first android:orientation="vertical" android:layout_width="fill_parent"
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You must call removeView() on the child&#39;s parent first android:layout_height="fill_parent">
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You must call removeView() on the child&#39;s parent first 6
You must call removeView() on the child&#39;s parent first <textview android:id="@+id/tv1" android:layout_gravity="center_vertical"
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You must call removeView() on the child&#39;s parent first android:layout_width="wrap_content" android:layout_height="wrap_content"
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You must call removeView() on the child&#39;s parent first />
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You must call removeView() on the child&#39;s parent first 10
You must call removeView() on the child&#39;s parent first <textview android:id="@+id/tv2" android:layout_gravity="center_vertical"
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You must call removeView() on the child&#39;s parent first 12
You must call removeView() on the child&#39;s parent first />
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You must call removeView() on the child&#39;s parent first 14
You must call removeView() on the child&#39;s parent first <textview android:id="@+id/tv3"
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You must call removeView() on the child&#39;s parent first android:layout_gravity="center_vertical" android:layout_width="wrap_content"
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You must call removeView() on the child&#39;s parent first android:layout_height="wrap_content" />
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You must call removeView() on the child&#39;s parent first 18
You must call removeView() on the child&#39;s parent first <imageview android:src="@drawable/line" android:layout_width="fill_parent"
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You must call removeView() on the child&#39;s parent first android:layout_height="fill_parent" />
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You must call removeView() on the child&#39;s parent first 21
You must call removeView() on the child&#39;s parent first </linearlayout>
如果你需要使用这个布局xml文件，并根据自己的需要，将其中三个textview的文字做更改，则在代码中应该这样去使用：
1
You must call removeView() on the child&#39;s parent first You must call removeView() on the child&#39;s parent first You must call removeView() on the child&#39;s parent first You must call removeView() on the child&#39;s parent first layoutinflater inflate = (layoutinflater)
You must call removeView() on the child&#39;s parent first getsystemservice(context.layout_inflater_service);
You must call removeView() on the child&#39;s parent first linearlayout layout = (linearlayout)inflate.inflate(r.layout.poemshowlist, null);
You must call removeView() on the child&#39;s parent first You must call removeView() on the child&#39;s parent first ((textview)layout.findviewbyid(r.id.tv1)).settext(text1);
You must call removeView() on the child&#39;s parent first ((textview)layout.findviewbyid(r.id.tv2)).settext(text2);
You must call removeView() on the child&#39;s parent first ((textview)layout.findviewbyid(r.id.tv3)).settext(text3);
You must call removeView() on the child&#39;s parent first You must call removeView() on the child&#39;s parent first linearlayout ll= new linearlayout(this);
You must call removeView() on the child&#39;s parent first ll.addview(layout);
You must call removeView() on the child&#39;s parent first setcontentview(ll);
You must call removeView() on the child&#39;s parent first You must call removeView() on the child&#39;s parent first You must call removeView() on the child&#39;s parent first You must call removeView() on the child&#39;s parent first You must call removeView() on the child&#39;s parent first 
