片段 - 指定的子节点已有父节点.您必须首先在孩子的父母上调用removeView()

Question

我收到了这个错误.我尝试了很多解决方案,但我还是想解决这个问题.帮我!我需要使用片段将表面视图和按钮添加到活动中.

CamActivity.java:

public class CamActivity extends FragmentActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_cam);

        FragmentManager fm = getSupportFragmentManager();

        Fragment fragment = fm.findFragmentById(R.id.fragmentContainer);

        if(fragment == null) {
            fragment = new CamFragment();
            fm.beginTransaction()
            .add(R.id.fragmentContainer, fragment)
            .commit();
        }
    }
}

CamFragment.java:

public class CamFragment extends Fragment {

    private static final String TAG = "CamFragment";

    private Camera mCamera;
    private SurfaceView mSurfaceView;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup parent, Bundle savedInstanceState){
    View v = inflater.inflate(R.layout.camera_fragment, parent);

    Button capturePic = (Button)v.findViewById(R.id.img_capture);
    capturePic.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            getActivity().finish();
        }
    });

    mSurfaceView = (SurfaceView)v.findViewById(R.id.surfaceView1);
    return v;
}

}

错误:

04-18 13:24:12.735: E/AndroidRuntime(6321): FATAL EXCEPTION: main
04-18 13:24:12.735: E/AndroidRuntime(6321): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.pack.camdictionary/com.pack.camdictionary.CamActivity}: java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1728)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1747)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.app.ActivityThread.access$1500(ActivityThread.java:155)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:993)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.os.Handler.dispatchMessage(Handler.java:130)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.os.Looper.loop(SourceFile:351)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.app.ActivityThread.main(ActivityThread.java:3814)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at java.lang.reflect.Method.invokeNative(Native Method)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at java.lang.reflect.Method.invoke(Method.java:538)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:901)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:659)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at dalvik.system.NativeStart.main(Native Method)
04-18 13:24:12.735: E/AndroidRuntime(6321): Caused by: java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.view.ViewGroup.addViewInner(ViewGroup.java:2007)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.view.ViewGroup.addView(ViewGroup.java:1902)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.view.ViewGroup.addView(ViewGroup.java:1859)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.view.ViewGroup.addView(ViewGroup.java:1839)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.support.v4.app.NoSaveStateFrameLayout.wrap(NoSaveStateFrameLayout.java:40)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:931)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1104)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1467)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:570)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1166)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.app.Activity.performStart(Activity.java:3837)
04-18 13:24:12.735: E/AndroidRuntime(6321):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1701)
04-18 13:24:12.735: E/AndroidRuntime(6321):     ... 11 more

Answer 1

尝试更换

View v = inflater.inflate(R.layout.camera_fragment, parent);

同

View v = inflater.inflate(R.layout.camera_fragment, parent, false);

要么

View v = inflater.inflate(R.layout.camera_fragment, null);

Answer 2

这个问题已经得到解答,但我仍然想添加false作为第三个参数的原因.

inflate()方法有三个参数:

• 要扩充的布局的资源ID.
• ViewGroup是膨胀布局的父级.传递容器非常重要,以便系统将布局参数应用于膨胀布局的根视图,该布局由其所在的父视图指定.
• 一个布尔值,指示在充气期间是否应将膨胀的布局附加到ViewGroup(第二个参数).(在这种情况下,这是错误的,因为系统已经将膨胀的布局插入到容器中 - 传递true会在最终布局中创建冗余视图组.)

资料来源:http: //developer.android.com/guide/components/fragments.html

Answer 3

就我而言，我setTransition()在FragmentTransaction. 下面的代码对我有用：

override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
                              savedInstanceState: Bundle?): View? {

        if(this::rootView.isInitialized){
            if(rootView.getParent() != null){
                (rootView.getParent() as ViewGroup).endViewTransition(rootView)
            }
            return this.rootView

        }

        ...

}

当您在片段之间反复切换时，可能会发生这种情况，由于正在进行的转换，视图没有时间真正与父级分离。

Answer 4

我正在使用 API 26.0.2，在我的情况下，崩溃是由于为我的片段设置的自定义动画而发生的。注释掉设置自定义动画的调用，修复了问题。

fragmentTransaction.setCustomAnimations(android.R.anim.fade_in, android.R.anim.fade_out);