java.lang.NullPointerException: Attempt to invoke virtual method 'int me.yokeyword.fragmentation.anim.FragmentAnimator.getEnter()' on a null object reference

[nicai1900]

#问题出现概率：必现

复现方法

APP启动后，到系统权限设置界面去关闭APP的某个权限，会导致APP进程退出，重新打开APP，就会崩溃

#手机系统：6.0以上

• Lib 1.3.3
• Support Lib 27.1.0
• Log

Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'int me.yokeyword.fragmentation.anim.FragmentAnimator.getEnter()' on a null object reference at me.yokeyword.fragmentation.helper.internal.AnimatorHelper.initEnterAnim(AnimatorHelper.java:63) at me.yokeyword.fragmentation.helper.internal.AnimatorHelper.notifyChanged(AnimatorHelper.java:29) at me.yokeyword.fragmentation.helper.internal.AnimatorHelper.<init>(AnimatorHelper.java:24) at me.yokeyword.fragmentation.SupportFragmentDelegate.onCreate(SupportFragmentDelegate.java:117)

• Screenshots

In addition, we do not accept issues unrelated to Fragmentation.

[YoKeyword]

@nicai1900 进程被杀后会做恢复操作，恢复代码在这里

1、复现的机型是？
2、Demo不更改任何代码是否可以复现？

[nicai1900]

@YoKeyword

1、复现的机型是？ 与机型无关，6.0以上需要动态权限就会

2、和哪个Demo无关，问题是必现的。在系统权限管理界面，动态开关APP的权限，进程被干掉，重新打开APP时，savedInstanceState 不为空，但是从savedInstanceState反序列化回来的mFragmentAnimator是空的

因此崩溃了。

SupportFragmentDelegate.java:108

  
    public void onCreate(@Nullable Bundle savedInstanceState) {
       
        //  重新打开APP时，savedInstanceState != null
        if (savedInstanceState == null) {
            getFragmentAnimator();
        } else {
            mSaveInstanceState = savedInstanceState;
            //  这里反序列化回来的结果是null
            mFragmentAnimator = savedInstanceState.getParcelable(TransactionDelegate.FRAGMENTATION_STATE_SAVE_ANIMATOR);
            mIsHidden = savedInstanceState.getBoolean(TransactionDelegate.FRAGMENTATION_STATE_SAVE_IS_HIDDEN);
            mContainerId = savedInstanceState.getInt(TransactionDelegate.FRAGMENTATION_ARG_CONTAINER);

            // RootFragment
            if (mRootStatus != STATUS_UN_ROOT) {
                FragmentationMagician.reorderIndices(mFragment.getFragmentManager());
            }
        }
}

[YoKeyword]

@nicai1900 让我很困扰的是： 确实做了恢复操作， 而且我一直无法复现该问题 （即使按你的场景去尝试）

为了更好的排查该问题，可否留个联系方式QQ / 微信，我们进一步交流该问题？

[nicai1900]

@YoKeyword 我的微信号 zhengjie1900

[z1060932884]

这个问题解决了吗

[gys0000]

这个问题确实跟机型无关，长时间后台再进到app里面就会出现这样的问题。应该是 mFragmentAnimator为空了，
if (onCreateFragmentAnimator() != null) {
super.onCreate(savedInstanceState);
}
我再继承的界面里面这样改不知道会不会解决这样的问题，希望能交流一下。我的微信：li747921695

[nicai1900]

@YoKeyword 问题解决了，我自己的错

自己实现了ISupportFragment 接口，漏了复写下面的接口了，因此导致没有保存mFragmentAnimator的数据。

    override fun onSaveInstanceState(outState: Bundle) {
        super.onSaveInstanceState(outState)
        delegate.onSaveInstanceState(outState)
    }

[z1060932884]

Caused by java.lang.NullPointerException: Attempt to invoke virtual method 'int me.yokeyword.fragmentation.anim.FragmentAnimator.getEnter()' on a null object reference
me.yokeyword.fragmentation.helper.internal.AnimatorHelper.initEnterAnim (AnimatorHelper.java:63)
me.yokeyword.fragmentation.helper.internal.AnimatorHelper.notifyChanged (AnimatorHelper.java:29)
me.yokeyword.fragmentation.helper.internal.AnimatorHelper.<init> (AnimatorHelper.java:24)
me.yokeyword.fragmentation.SupportFragmentDelegate.onCreate (SupportFragmentDelegate.java:120)
com.pinyou.bingobuy.base.PresenterFragment.onCreate (PresenterFragment.java:89)
android.support.v4.app.Fragment.performCreate (Fragment.java:2068)
android.support.v4.app.FragmentManagerImpl.moveToState (FragmentManager.java:1055)
android.support.v4.app.FragmentManagerImpl.moveToState (FragmentManager.java:1290)
android.support.v4.app.FragmentManagerImpl.moveToState (FragmentManager.java:1272)
android.support.v4.app.FragmentManagerImpl.dispatchCreate (FragmentManager.java:2144)
android.support.v4.app.Fragment.restoreChildFragmentState (Fragment.java:1284)
android.support.v4.app.Fragment.onCreate (Fragment.java:1255)
com.pinyou.bingobuy.base.PresenterFragment.onCreate (PresenterFragment.java:88)
android.support.v4.app.Fragment.performCreate (Fragment.java:2068)
android.support.v4.app.FragmentManagerImpl.moveToState (FragmentManager.java:1055)
android.support.v4.app.FragmentManagerImpl.moveToState (FragmentManager.java:1290)
android.support.v4.app.FragmentManagerImpl.moveToState (FragmentManager.java:1272)
android.support.v4.app.FragmentManagerImpl.dispatchCreate (FragmentManager.java:2144)
android.support.v4.app.FragmentController.dispatchCreate (FragmentController.java:190)
android.support.v4.app.FragmentActivity.onCreate (FragmentActivity.java:351)
android.support.v7.app.AppCompatActivity.onCreate (AppCompatActivity.java:85)
com.pinyou.bingobuy.base.Activity.onCreate (Activity.java:49)
android.app.Activity.performCreate (Activity.java:6303)
android.app.Instrumentation.callActivityOnCreate (Instrumentation.java:1108)
android.app.ActivityThread.performLaunchActivity (ActivityThread.java:2376)
android.app.ActivityThread.handleLaunchActivity (ActivityThread.java:2483)
android.app.ActivityThread.access$900 (ActivityThread.java:153)
android.app.ActivityThread$H.handleMessage (ActivityThread.java:1349)
android.os.Handler.dispatchMessage (Handler.java:102)
android.os.Looper.loop (Looper.java:148)
android.app.ActivityThread.main (ActivityThread.java:5438)
java.lang.reflect.Method.invoke (Method.java)
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run (ZygoteInit.java:738)
com.android.internal.os.ZygoteInit.main (ZygoteInit.java:628)

我也在实现ISupportFragment 的接口中重写了那个onSaveInstanceState（）方法，我自己怎么测都不会出现这个bug，但是bug收集工具收集了很多这个崩溃信息， 根据用户反馈就是长时间后台再进入就会出现这个问题。

[foolchen]

@z1060932884 v4包更新到27.1.1试试。
开发者模式中，把“不保留活动”打开应该就能复现了，应该是应用在后台被杀死，切换到前台重建时出了问题。

[YoKeyword]

@z1060932884 楼上2位同学一个同学是忘记在Fragment里delegate.onSaveInstanceState(outState)，一个同学是移除了Activity里的super.onSaveInstanceState()

所有检查Activity和Fragment的onSaveInstanceState()，看是否有复写或者忘记委托， 具体复现方式，可以按 @foolchen 提供的方式复现

[z1060932884]

找到原因了 ，进程杀死时onSaveInstanceState方法在执行次数比onCreate方法执行次数少，然后查看自己写的代码，去掉了一个Fragment加载Fragment的界面就好了。 @YoKeyword @foolchen