原文:https://blog.csdn.net/lxd_love_lgc/article/details/105650993
之前在做ViewPage+Fragment 横竖屏切换时 遇到报错了,搞了好久才解决,所以记录一下:
The specified child already has a parent. You must call removeView() on the child’s parent first.
报错信息如下:
java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3194)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3302)
at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:5368)
at android.app.ActivityThread.-wrap19(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1897)
at android.os.Handler.dispatchMessage(Handler.java:108)
at android.os.Looper.loop(Looper.java:166)
at android.app.ActivityThread.main(ActivityThread.java:7425)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:245)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:921)
Caused by: 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:4976)
at android.view.ViewGroup.addView(ViewGroup.java:4807)
at androidx.viewpager.widget.ViewPager.addView(ViewPager.java:1485)
at android.view.ViewGroup.addView(ViewGroup.java:4747)
at android.view.ViewGroup.addView(ViewGroup.java:4720)
at androidx.fragment.app.FragmentStateManager.createView(FragmentStateManager.java:326)
at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1187)
at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1356)
at androidx.fragment.app.FragmentManager.moveFragmentToExpectedState(FragmentManager.java:1434)
at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1497)
at androidx.fragment.app.FragmentManager.dispatchStateChange(FragmentManager.java:2625)
at androidx.fragment.app.FragmentManager.dispatchActivityCreated(FragmentManager.java:2577)
at androidx.fragment.app.FragmentController.dispatchActivityCreated(FragmentController.java:247)
at androidx.fragment.app.FragmentActivity.onStart(FragmentActivity.java:541)
at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1339)
at android.app.Activity.performStart(Activity.java:7392)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3157)
... 10 more","40","0",
主要报错原因的就是这句: java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child’s parent first.
指定的孩子已经有一个父母。您必须先在孩子的父母上调用removeView()。
两种解决办法
第一种: 获取view 的父类 并移除
private View view;
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
if (view == null) {
view = inflater.inflate(R.layout.message_center_fragment, container, false);
}
ViewGroup parent = (ViewGroup) view.getParent();
if (parent != null) {
parent.removeView(view);
}
@Override
public void onDestroyView() {
super.onDestroyView();
if (view != null) {
ViewGroup parentView = (ViewGroup) view.getParent();
if (parentView != null) {
parentView.removeView(view);
}
}
}
不过这种方式试了一下不一定奏效
第二种方法:
在Fragment 所以依赖的activity 的AndroidManifest.xml
中加一个配置项
android:configChanges="orientation|keyboardHidden|screenSize" />
该配置项的作用: activity在横竖屏切换的时候不重新调用onCreate方法
亲测有效
希望对同样遇到这个问题的同学有所帮助