我有一个Live Android应用程序,从市场上我收到了以下堆栈跟踪,我不知道为什么它会发生,因为它不是发生在应用程序代码中,而是由应用程序的一些或其他事件引起的(假设)

我没有使用片段,仍然有一个FragmentManager的参考。 如果有人能揭示一些隐藏的事实,以避免这类问题:

java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState
at android.app.FragmentManagerImpl.checkStateLoss(FragmentManager.java:1109)
at android.app.FragmentManagerImpl.popBackStackImmediate(FragmentManager.java:399)
at android.app.Activity.onBackPressed(Activity.java:2066)
at android.app.Activity.onKeyDown(Activity.java:1962)
at android.view.KeyEvent.dispatch(KeyEvent.java:2482)
at android.app.Activity.dispatchKeyEvent(Activity.java:2274)
at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchKeyEvent(PhoneWindow.java:1668)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchKeyEvent(PhoneWindow.java:1720)
at com.android.internal.policy.impl.PhoneWindow.superDispatchKeyEvent(PhoneWindow.java:1258)
at android.app.Activity.dispatchKeyEvent(Activity.java:2269)
at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchKeyEvent(PhoneWindow.java:1668)
at android.view.ViewRoot.deliverKeyEventPostIme(ViewRoot.java:2851)
at android.view.ViewRoot.handleFinishedEvent(ViewRoot.java:2824)
at android.view.ViewRoot.handleMessage(ViewRoot.java:2011)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:132)
at android.app.ActivityThread.main(ActivityThread.java:4025)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:491)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:841)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:599)
at dalvik.system.NativeStart.main(Native Method)  

当前回答

我有这个问题。但是我认为这个问题与commit和commitAllowStateLoss无关。

下面的堆栈跟踪和异常消息是关于commit()的。

java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState
at android.support.v4.app.FragmentManagerImpl.checkStateLoss(FragmentManager.java:1341)
at android.support.v4.app.FragmentManagerImpl.enqueueAction(FragmentManager.java:1352)
at android.support.v4.app.BackStackRecord.commitInternal(BackStackRecord.java:595)
at android.support.v4.app.BackStackRecord.commit(BackStackRecord.java:574)

但是这个异常是由onBackPressed()引起的

java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState
at android.support.v4.app.FragmentManagerImpl.checkStateLoss(Unknown Source)
at android.support.v4.app.FragmentManagerImpl.popBackStackImmediate(Unknown Source)
at android.support.v4.app.FragmentActivity.onBackPressed(Unknown Source)

它们都是由checkStateLoss()引起的

private void checkStateLoss() {
    if (mStateSaved) {
        throw new IllegalStateException(
                "Can not perform this action after onSaveInstanceState");
    }
    if (mNoTransactionsBecause != null) {
        throw new IllegalStateException(
                "Can not perform this action inside of " + mNoTransactionsBecause);
    }

mStateSaved在onSaveInstanceState之后为真。

这个问题很少发生。我从来没有遇到过这个问题。我不能再出现这个问题。

我找到了25517号

它可能在下列情况下发生

Back键在onSaveInstanceState之后,但在新活动开始之前被调用。 在代码中使用onStop()

我不确定问题的根源是什么。 所以我用了一个丑陋的方法。

@Override
public void onBackPressed() {

    try{
        super.onBackPressed();
    }catch (IllegalStateException e){
        // can output some information here
        finish();
    }
}

其他回答

读 http://chris-alexander.co.uk/on-engineering/dev/android-fragments-within-fragments/

篇文章。 fragment. isresume()检查帮助我在onDestroyView w/o使用onSaveInstanceState方法。

我得到这个异常时,我按下后退按钮取消意图选择器在我的地图片段活动。 我通过替换onResume()的代码来解决这个问题(我在那里初始化片段和提交事务)到onStart(),应用程序现在工作正常。 希望能有所帮助。

我在我的应用程序中有同样的问题。我已经解决了这个问题,只是调用super.onBackPressed();并在当前类上调用commitAllowingStateLoss()。

I solved the issue with onconfigurationchanged. The trick is that according to android activity life cycle, when you explicitly called an intent(camera intent, or any other one); the activity is paused and onsavedInstance is called in that case. When rotating the device to a different position other than the one during which the activity was active; doing fragment operations such as fragment commit causes Illegal state exception. There are lots of complains about it. It's something about android activity lifecycle management and proper method calls. To solve it I did this: 1-Override the onsavedInstance method of your activity, and determine the current screen orientation(portrait or landscape) then set your screen orientation to it before your activity is paused. that way the activity you lock the screen rotation for your activity in case it has been rotated by another one. 2-then , override onresume method of activity, and set your orientation mode now to sensor so that after onsaved method is called it will call one more time onconfiguration to deal with the rotation properly.

你可以复制/粘贴这段代码到你的活动来处理它:

@Override
protected void onSaveInstanceState(Bundle outState) {       
    super.onSaveInstanceState(outState);

    Toast.makeText(this, "Activity OnResume(): Lock Screen Orientation ", Toast.LENGTH_LONG).show();
    int orientation =this.getDisplayOrientation();
    //Lock the screen orientation to the current display orientation : Landscape or Potrait
    this.setRequestedOrientation(orientation);
}

//A method found in stackOverflow, don't remember the author, to determine the right screen orientation independently of the phone or tablet device 
public int getDisplayOrientation() {
    Display getOrient = getWindowManager().getDefaultDisplay();

    int orientation = getOrient.getOrientation();

    // Sometimes you may get undefined orientation Value is 0
    // simple logic solves the problem compare the screen
    // X,Y Co-ordinates and determine the Orientation in such cases
    if (orientation == Configuration.ORIENTATION_UNDEFINED) {
        Configuration config = getResources().getConfiguration();
        orientation = config.orientation;

        if (orientation == Configuration.ORIENTATION_UNDEFINED) {
        // if height and widht of screen are equal then
        // it is square orientation
            if (getOrient.getWidth() == getOrient.getHeight()) {
                orientation = Configuration.ORIENTATION_SQUARE;
            } else { //if widht is less than height than it is portrait
                if (getOrient.getWidth() < getOrient.getHeight()) {
                    orientation = Configuration.ORIENTATION_PORTRAIT;
                } else { // if it is not any of the above it will defineitly be landscape
                    orientation = Configuration.ORIENTATION_LANDSCAPE;
                }
            }
        }
    }
    return orientation; // return value 1 is portrait and 2 is Landscape Mode
}

@Override
public void onResume() {
    super.onResume();
    Toast.makeText(this, "Activity OnResume(): Unlock Screen Orientation ", Toast.LENGTH_LONG).show();
    setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_SENSOR);
} 

当我试图在onActivityForResult()方法中显示片段时,我总是得到这个,所以接下来的问题是:

我的活动暂停和停止,这意味着,onSaveInstanceState()已经被调用(对于pre-Honeycomb和post-Honeycomb设备)。 在任何结果的情况下,我使事务显示/隐藏片段,这导致这个IllegalStateException。

接下来我做的是:

增加了确定我想要的动作是否完成的值(例如,从camere - isPhotoTaken中拍摄照片)-它可以是布尔值或整数值,这取决于你需要多少不同的事务。 在重写onResumeFragments()方法中,我检查了我的值,并在我需要的片段事务之后。在这种情况下,commit()没有在onSaveInstanceState之后执行,因为状态是在onResumeFragments()方法中返回的。