java.lang.IllegalStateException:指定的子级已有父级

Question

我正在使用片段,当我第一次实例化片段时.但第二次我得到了这个例外.我找不到出错的地方？

 04-04 08:51:54.320: E/AndroidRuntime(29713): FATAL EXCEPTION: main
    04-04 08:51:54.320: E/AndroidRuntime(29713): java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
    04-04 08:51:54.320: E/AndroidRuntime(29713):    at android.view.ViewGroup.addViewInner(ViewGroup.java:3013)
    04-04 08:51:54.320: E/AndroidRuntime(29713):    at android.view.ViewGroup.addView(ViewGroup.java:2902)
    04-04 08:51:54.320: E/AndroidRuntime(29713):    at android.view.ViewGroup.addView(ViewGroup.java:2859)
    04-04 08:51:54.320: E/AndroidRuntime(29713):    at android.view.ViewGroup.addView(ViewGroup.java:2839)
    04-04 08:51:54.320: E/AndroidRuntime(29713):    at android.support.v4.app.NoSaveStateFrameLayout.wrap(Unknown Source)
    04-04 08:51:54.320: E/AndroidRuntime(29713):    at android.support.v4.app.FragmentManagerImpl.moveToState(Unknown Source)
    04-04 08:51:54.320: E/AndroidRuntime(29713):    at android.support.v4.app.FragmentManagerImpl.moveToState(Unknown Source)
    04-04 08:51:54.320: E/AndroidRuntime(29713):    at android.support.v4.app.BackStackRecord.run(Unknown Source)
    04-04 08:51:54.320: E/AndroidRuntime(29713):    at android.support.v4.app.FragmentManagerImpl.execPendingActions(Unknown Source)
    04-04 08:51:54.320: E/AndroidRuntime(29713):    at android.support.v4.app.FragmentManagerImpl$1.run(Unknown Source)
    04-04 08:51:54.320: E/AndroidRuntime(29713):    at android.os.Handler.handleCallback(Handler.java:587)
    04-04 08:51:54.320: E/AndroidRuntime(29713):    at android.os.Handler.dispatchMessage(Handler.java:92)
    04-04 08:51:54.320: E/AndroidRuntime(29713):    at android.os.Looper.loop(Looper.java:132)
    04-04 08:51:54.320: E/AndroidRuntime(29713):    at android.app.ActivityThread.main(ActivityThread.java:4126)
    04-04 08:51:54.320: E/AndroidRuntime(29713):    at java.lang.reflect.Method.invokeNative(Native Method)
    04-04 08:51:54.320: E/AndroidRuntime(29713):    at java.lang.reflect.Method.invoke(Method.java:491)
    04-04 08:51:54.320: E/AndroidRuntime(29713):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:844)
    04-04 08:51:54.320: E/AndroidRuntime(29713):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:602)
    04-04 08:51:54.320: E/AndroidRuntime(29713):    at dalvik.system.NativeStart.main(Native Method)

这是我点击列表片段的元素时所做的事情.

// If we are not currently showing a fragment for the new
 // position, we need to create and install a new one.
 RouteSearchFragment df = RouteSearchFragment.newInstance(index);

 // Execute a transaction, replacing any existing fragment
 // with this one inside the frame.
 FragmentTransaction ft = fragmentManager.beginTransaction();
 ft.replace(R.id.details_full, df);
 ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
 ft.commit();

第一次它是好的,我从列表中单击element2,它也没关系; 但是当我回到element1时,我遇到了这个bug.

感谢大家!

Answer 1

很抱歉发布一个旧问题,但我能够使用完全不同的解决方案来修复它.我得到了这个异常,但我改变了我的onCreatView覆盖的第一行:

View result = inflater.inflate(R.layout.customer_layout, container);

......对此:

View result = inflater.inflate(R.layout.customer_layout, container, false);

我不知道为什么但是使用接受布尔值的覆盖作为第三个参数修复它.我认为它告诉Fragment和/或Activity不要使用"容器"作为新创建的View的父级.HTH!

Answer 2

我多次面对这个问题.请添加以下代码以解决此问题:

@Override
    public void onDestroyView() {
        super.onDestroyView();
        if (view != null) {
            ViewGroup parentViewGroup = (ViewGroup) view.getParent();
            if (parentViewGroup != null) {
                parentViewGroup.removeAllViews();
            }
        }
    }

谢谢

Answer 3

如果你有这个说法..

View view = inflater.inflate(R.layout.fragment1, container);//may be Incorrect 

然后尝试这个..添加false作为第三个参数..可能它可以帮助..

View view = inflater.inflate(R.layout.fragment1, container, false);//correct one

Answer 4

当你OnCreateView在RouteSearchFragment班级中覆盖时,你有吗？

if(view != null) {
    return view; 
}

代码段？

如果是这样,删除return语句应该可以解决您的问题.

如果您不想重新生成视图数据,可以保留代码并返回视图,而如果您从父节点中删除此视图,则可以使用onDestroyView()方法,如下所示:

    @Override
    public void onDestroyView() {
        super.onDestroyView();
        if (view != null) {
            ViewGroup parent = (ViewGroup) view.getParent();
            if (parent != null) {
                parent.removeAllViews();
            }
        }
    }

Answer 5

我在片段中有这个代码,如果我试图回到这个片段,它就会崩溃

if (mRootView == null) {
    mRootView = inflater.inflate(R.layout.fragment_main, container, false);
} 

在这个帖子上收集答案之后,我意识到mRootView的父级仍然将mRootView作为子级.所以,这是我的修复.

if (mRootView == null) {
    mRootView = inflater.inflate(R.layout.fragment_main, container, false);
} else {
    ((ViewGroup) mRootView.getParent()).removeView(mRootView);
}

希望这可以帮助

Answer 6

当onCreateView()返回的视图不是被夸大的视图时,也会发生这种情况.

例:

View rootView = inflater.inflate(R.layout.my_fragment, container, false);

TextView textView = (TextView) rootView.findViewById(R.id.text_view);
textView.setText("Some text.");

return textView;

固定:

return rootView;

代替:

return textView; // or whatever you returned

Answer 7

我有这个问题,无法用Java代码解决它.问题出在我的xml上.

我试图将textView添加到容器中,但已将textView包装在LinearLayout中.

这是原始的xml文件:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    
    <TextView xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@android:id/text1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textAppearance="?android:attr/textAppearanceListItemSmall"
        android:gravity="center_vertical"
        android:paddingLeft="16dp"
        android:paddingRight="16dp"
        android:textColor="#fff"
        android:background="?android:attr/activatedBackgroundIndicator"
        android:minHeight="?android:attr/listPreferredItemHeightSmall"/>

</LinearLayout>

现在删除了LinearLayout:

<TextView xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@android:id/text1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textAppearance="?android:attr/textAppearanceListItemSmall"
        android:gravity="center_vertical"
        android:paddingLeft="16dp"
        android:paddingRight="16dp"
        android:textColor="#fff"
        android:background="?android:attr/activatedBackgroundIndicator"
        android:minHeight="?android:attr/listPreferredItemHeightSmall"/>

这对我来说似乎并不多,但它完成了诀窍,我根本没有改变我的Java代码.它全部在xml中.