Unable to pause activity, Failure saving state

Question

I'm building an Android app right now, and if I press the Home button or lock the screen after a given scenario (it's really specific), my app crashes with the error:

10-26 13:57:50.132: E/AndroidRuntime(8663): FATAL EXCEPTION: main
10-26 13:57:50.132: E/AndroidRuntime(8663): java.lang.RuntimeException: Unable to pause activity {.views.MainActivity}: java.lang.IllegalStateException: Failure saving state: active LoginFragment{4053d5a0} has cleared index: -1
10-26 13:57:50.132: E/AndroidRuntime(8663):     at android.app.ActivityThread.performPauseActivity(ActivityThread.java:2365)
10-26 13:57:50.132: E/AndroidRuntime(8663):     at android.app.ActivityThread.performPauseActivity(ActivityThread.java:2322)
10-26 13:57:50.132: E/AndroidRuntime(8663):     at android.app.ActivityThread.handlePauseActivity(ActivityThread.java:2302)
10-26 13:57:50.132: E/AndroidRuntime(8663):     at android.app.ActivityThread.access$1700(ActivityThread.java:117)
10-26 13:57:50.132: E/AndroidRuntime(8663):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:949)
10-26 13:57:50.132: E/AndroidRuntime(8663):     at android.os.Handler.dispatchMessage(Handler.java:99)
10-26 13:57:50.132: E/AndroidRuntime(8663):     at android.os.Looper.loop(Looper.java:130)
10-26 13:57:50.132: E/AndroidRuntime(8663):     at android.app.ActivityThread.main(ActivityThread.java:3694)
10-26 13:57:50.132: E/AndroidRuntime(8663):     at java.lang.reflect.Method.invokeNative(Native Method)
10-26 13:57:50.132: E/AndroidRuntime(8663):     at java.lang.reflect.Method.invoke(Method.java:507)
10-26 13:57:50.132: E/AndroidRuntime(8663):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
10-26 13:57:50.132: E/AndroidRuntime(8663):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
10-26 13:57:50.132: E/AndroidRuntime(8663):     at dalvik.system.NativeStart.main(Native Method)
10-26 13:57:50.132: E/AndroidRuntime(8663): Caused by: java.lang.IllegalStateException: Failure saving state: active LoginFragment{4053d5a0} has  cleared index: -1
10-26 13:57:50.132: E/AndroidRuntime(8663):     at android.support.v4.app.FragmentManagerImpl.saveAllState(FragmentManager.java:1695)
10-26 13:57:50.132: E/AndroidRuntime(8663):     at android.support.v4.app.FragmentActivity.onSaveInstanceState(FragmentActivity.java:499)
10-26 13:57:50.132: E/AndroidRuntime(8663):     at views.MainActivity.onSaveInstanceState(MainActivity.java:62)
10-26 13:57:50.132: E/AndroidRuntime(8663):     at android.app.Activity.performSaveInstanceState(Activity.java:1042)
10-26 13:57:50.132: E/AndroidRuntime(8663):     at android.app.Instrumentation.callActivityOnSaveInstanceState(Instrumentation.java:1181)
10-26 13:57:50.132: E/AndroidRuntime(8663):     at android.app.ActivityThread.performPauseActivity(ActivityThread.java:2347)
10-26 13:57:50.132: E/AndroidRuntime(8663):     ... 12 more

I have no idea what this error comes from and what the general cause of this error is.

Edit:
I'm sorry, I'll give out some more information. Basically, I have a FragmentActivity (which is my Tabhost) and each tab is a fragment from which I can navigate to another fragment.

The specific scenario is as following:

• Application opens, Tab 0 with Fragment 0 (LoginFragment) is displayed.
• User logs in, LoginFragment gets replaced with ProfileFragment.
• From the ProfileFragment, the user has the ability to logout, and does so, which replaces the Profilefragment with Loginfragment again.
• User navigates to different Tab from TabHost.
• User navigates back to the original Tab.
• User then locks screen / uses the Home button, crashing the application with the given error.

I only get the error on this specific scenario.

The error originates from the TabManager class within the TabHost FragmentActivity, here is the code (mainly from the Android FragmentTabs example, with a few minor adjustments):

public static class TabManager implements TabHost.OnTabChangeListener {
    private final FragmentActivity mActivity;
    private final TabHost mTabHost;
    private final int mContainerId;
    private final HashMap<String, TabInfo> mTabs = new HashMap<String, TabInfo>();
    TabInfo mLastTab;

    static final class TabInfo {
        private final String tag;
        private final Class<?> clss;
        private final Bundle args;
        private Fragment fragment;

        TabInfo(String _tag, Class<?> _class, Bundle _args) {
            tag = _tag;
            clss = _class;
            args = _args;
        }
    }

    static class DummyTabFactory implements TabHost.TabContentFactory {
        private final Context mContext;

        public DummyTabFactory(Context context) {
            mContext = context;
        }

        public View createTabContent(String tag) {
            View v = new View(mContext);
            v.setMinimumWidth(0);
            v.setMinimumHeight(0);
            return v;
        }
    }

    public TabManager(FragmentActivity activity, TabHost tabHost, int containerId) {
        mActivity = activity;
        mTabHost = tabHost;
        mContainerId = containerId;
        mTabHost.setOnTabChangedListener(this);
    }

    public void addTab(TabHost.TabSpec tabSpec, Class<?> clss, Bundle args) {
        tabSpec.setContent(new DummyTabFactory(mActivity));
        String tag = tabSpec.getTag();

        TabInfo info = new TabInfo(tag, clss, args);

        // Check to see if we already have a fragment for this tab, probably
        // from a previously saved state.  If so, deactivate it, because our
        // initial state is that a tab isn't shown.
        info.fragment = mActivity.getSupportFragmentManager().findFragmentByTag(tag);
                if (info.fragment != null && !info.fragment.isDetached()) {
                    FragmentTransaction ft = mActivity.getSupportFragmentManager().beginTransaction();
                    ft.detach(info.fragment);
                    ft.commit();
                }

                mTabs.put(tag, info);
                mTabHost.addTab(tabSpec);
    }

    public void onTabChanged(String tabId) {

        TabInfo newTab = mTabs.get(tabId);
        if (mLastTab != newTab) {
            FragmentTransaction ft = mActivity.getSupportFragmentManager().beginTransaction();
            if (mLastTab != null) {
                if (mLastTab.fragment != null) {
                    ft.detach(mLastTab.fragment);
                }
            }
            if (newTab != null) {
                if (newTab.fragment == null) {
                    newTab.fragment = Fragment.instantiate(mActivity,
                            newTab.clss.getName(), newTab.args);
                    ft.add(mContainerId, newTab.fragment, newTab.tag);

                } else {
                    ft.attach(newTab.fragment);
                }
            }
            int backEntryCount = mActivity.getSupportFragmentManager().getBackStackEntryCount();
            if (backEntryCount > 1) {
                mActivity.getSupportFragmentManager().popBackStack(null, 0);
            }

            //If there's a current BackTrace, remove it and instantiate the original fragment of the selected tab.
            FragmentManager fm = mActivity.getSupportFragmentManager();
            if (fm.getBackStackEntryCount() >= 1) {
                fm.popBackStack();
                newTab.fragment.getFragmentManager().beginTransaction().add(mLastTab.fragment.getId(), newTab.fragment = Fragment.instantiate(mActivity,
                        newTab.clss.getName(), newTab.args));
            }
            if (mActivity.getSupportFragmentManager().findFragmentByTag("userprofile") != null) {
                Fragment fragment = mActivity.getSupportFragmentManager().findFragmentByTag("userprofile");
                ft.detach(fragment);

            }
            if (newTab.fragment.getClass().getName().contains("Login") && Preferences.getUser(mActivity).getApikey() != null) {
                ft.replace(mLastTab.fragment.getId(), new ProfileFragment(), "userprofile");
                ft.detach(newTab.fragment);
            }

            if (mActivity.getSupportFragmentManager().findFragmentByTag("Profile") != null) {
                if (mActivity.getSupportFragmentManager().findFragmentByTag("Profile").isDetached() == true) {
                    System.out.println(true);
                    Fragment fragment = mActivity.getSupportFragmentManager().findFragmentByTag("Profile");
                    mActivity.getSupportFragmentManager().beginTransaction().replace(fragment.getId(), new LoginFragment(), "Profile").commit();
                }
            }
            mLastTab = newTab;
            ft.commit();  
            mActivity.getSupportFragmentManager().executePendingTransactions();

        }
    }
}

Answer 1

Sorry for being late with this answer, but I found out why I had this error. For some reason I had multiple instances of my LoginFragment which was causing the crash. I removed some code so the fragment would be instanced only one time and I had no more crashes after that.