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

这对我很管用……我自己发现的…希望对你有所帮助!

1)不要有全局的“静态”FragmentManager / FragmentTransaction。

2) onCreate,总是初始化FragmentManager再次!

样本如下:-

public abstract class FragmentController extends AnotherActivity{
protected FragmentManager fragmentManager;
protected FragmentTransaction fragmentTransaction;
protected Bundle mSavedInstanceState;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    mSavedInstanceState = savedInstanceState;
    setDefaultFragments();
}

protected void setDefaultFragments() {
    fragmentManager = getSupportFragmentManager();
    //check if on orientation change.. do not re-add fragments!
    if(mSavedInstanceState == null) {
        //instantiate the fragment manager

        fragmentTransaction = fragmentManager.beginTransaction();

        //the navigation fragments
        NavigationFragment navFrag = new NavigationFragment();
        ToolbarFragment toolFrag = new ToolbarFragment();

        fragmentTransaction.add(R.id.NavLayout, navFrag, "NavFrag");
        fragmentTransaction.add(R.id.ToolbarLayout, toolFrag, "ToolFrag");
        fragmentTransaction.commitAllowingStateLoss();

        //add own fragment to the nav (abstract method)
        setOwnFragment();
    }
}

其他回答

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);
} 

这是我迄今为止遇到的最愚蠢的错误。我有一个片段应用程序工作完美的API < 11,并强制关闭API > 11。

我真的不知道他们在saveInstance调用的活动生命周期内改变了什么,但我在这里是我如何解决这个问题的:

@Override
protected void onSaveInstanceState(Bundle outState) {
    //No call for super(). Bug on API Level > 11.
}

我只是不调用.super(),一切都很好。我希望这将为您节省一些时间。

编辑:经过进一步研究,这是支持包中的一个已知错误。

如果你需要保存实例,并添加一些东西到你的outState Bundle,你可以使用以下方法:

@Override
protected void onSaveInstanceState(Bundle outState) {
    outState.putString("WORKAROUND_FOR_BUG_19917_KEY", "WORKAROUND_FOR_BUG_19917_VALUE");
    super.onSaveInstanceState(outState);
}

EDIT2:如果您试图在Activity在后台消失后执行事务,也可能会发生这种情况。为了避免这种情况,你应该使用commitAllowingStateLoss()

EDIT3: The above solutions were fixing issues in the early support.v4 libraries from what I can remember. But if you still have issues with this you MUST also read @AlexLockwood 's blog : Fragment Transactions & Activity State Loss Summary from the blog post (but I strongly recommend you to read it) : NEVER commit() transactions after onPause() on pre-Honeycomb, and onStop() on post-Honeycomb Be careful when committing transactions inside Activity lifecycle methods. Use onCreate(), onResumeFragments() and onPostResume() Avoid performing transactions inside asynchronous callback methods Use commitAllowingStateLoss() only as a last resort

当我在一个片段中使用startactivity时,我会得到这个异常;

当我改变使用startactivityforresult时,异常消失了:)

所以修复它的简单方法是使用startActivityForResult api:)

简单有效的解决方案:

遵循简单的步骤:

步骤1:在各自的片段中覆盖onSaveInstanceState状态。并从中移除super method。

@Override
public void onSaveInstanceState(Bundle outState) {
};

步骤2:使用CommitAllowingStateLoss();而不是commit();而片段操作。

fragmentTransaction.commitAllowingStateLoss();

当用户旋转屏幕以便加载与新方向相关的资源时,onSaveInstance将被调用。

有可能这个用户旋转了屏幕,然后按了后退按钮(因为也有可能这个用户在使用你的应用程序时摸不着他们的手机)