NullPointerException when opening Language & Input settings

Question

I have a rooted Lenovo P770, where I uninstalled several "system" apps, including the stock keyboard, TouchPal. After a factory reset I installed AnySoftKeyboard with adb (adb shell ime...), and now it works. However, I can no longer access Language & Input settings as I'm getting an "Unfortunately, Settings has stopped" message the moment I tap on the menu item. Here is the stacktrace from adb logcat:

W/dalvikvm( 8972): threadid=1: thread exiting with uncaught exception (group=0x40db2908)
E/AndroidRuntime( 8972): FATAL EXCEPTION: main
E/AndroidRuntime( 8972): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.android.settings/com.android.settings.SubSettings}: java.lang.NullPointerException
E/AndroidRuntime( 8972):        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2184)
E/AndroidRuntime( 8972):        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2211)
E/AndroidRuntime( 8972):        at android.app.ActivityThread.access$600(ActivityThread.java:149)
E/AndroidRuntime( 8972):        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1300)
E/AndroidRuntime( 8972):        at android.os.Handler.dispatchMessage(Handler.java:99)
E/AndroidRuntime( 8972):        at android.os.Looper.loop(Looper.java:153)
E/AndroidRuntime( 8972):        at android.app.ActivityThread.main(ActivityThread.java:5108)
E/AndroidRuntime( 8972):        at java.lang.reflect.Method.invokeNative(Native Method)
E/AndroidRuntime( 8972):        at java.lang.reflect.Method.invoke(Method.java:511)
E/AndroidRuntime( 8972):        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:993)
E/AndroidRuntime( 8972):        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:751)
E/AndroidRuntime( 8972):        at dalvik.system.NativeStart.main(Native Method)
E/AndroidRuntime( 8972): Caused by: java.lang.NullPointerException
E/AndroidRuntime( 8972):        at android.preference.PreferenceGroup.removePreferenceInt(PreferenceGroup.java:181)
E/AndroidRuntime( 8972):        at android.preference.PreferenceGroup.removePreference(PreferenceGroup.java:174)
E/AndroidRuntime( 8972):        at com.android.settings.VoiceInputOutputSettings.populateOrRemoveTtsPrefs(VoiceInputOutputSettings.java:144)
E/AndroidRuntime( 8972):        at com.android.settings.VoiceInputOutputSettings.populateOrRemovePreferences(VoiceInputOutputSettings.java:94)
E/AndroidRuntime( 8972):        at com.android.settings.VoiceInputOutputSettings.onCreate(VoiceInputOutputSettings.java:89)
E/AndroidRuntime( 8972):        at com.android.settings.inputmethod.InputMethodAndLanguageSettings.onCreate(InputMethodAndLanguageSettings.java:121)
E/AndroidRuntime( 8972):        at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:796)
E/AndroidRuntime( 8972):        at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1035)
E/AndroidRuntime( 8972):        at android.app.BackStackRecord.run(BackStackRecord.java:635)
E/AndroidRuntime( 8972):        at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1397)
E/AndroidRuntime( 8972):        at android.app.Activity.performStart(Activity.java:5030)
E/AndroidRuntime( 8972):        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2157)
E/AndroidRuntime( 8972):        ... 11 more
W/ActivityManager(  351):   Force finishing activity com.android.settings/.SubSettings
W/ActivityManager(  351):   Force finishing activity com.android.settings/.Settings

Since the stacktrace mentions VoiceInputOutputSettings, I tried installing the Google app (as far as I understand, it provides voice recognition capabilities), but that changed nothing. I have also tried installing TouchPal from the market, to no effect either.

Here are the entries from settings.db that seem relevant:

_id,name,value
72,selected_spell_checker,com.google.android.inputmethod.latin/com.android.inputmethod.latin.spellcheck.AndroidSpellCheckerService
73,selected_spell_checker_subtype,0
94,input_methods_subtype_history,com.google.android.inputmethod.latin/com.android.inputmethod.latin.LatinIME;834845621:com.menny.android.anysoftkeyboard/.SoftKeyboard;-1
95,selected_input_method_subtype,-1
96,default_input_method,com.menny.android.anysoftkeyboard/.SoftKeyboard
97,enabled_input_methods,com.menny.android.anysoftkeyboard/.SoftKeyboard

How can I fix this crash?

Answer 1

Fixed by installing Google TTS.

---

This could be determined from the stacktrace and the settings app source code:

public void onCreate() {
    mParent = mFragment.getPreferenceScreen();
    mVoiceCategory = (PreferenceCategory) mParent.findPreference(KEY_VOICE_CATEGORY);
    mTtsSettingsPref = mVoiceCategory.findPreference(KEY_TTS_SETTINGS);

    populateOrRemovePreferences();
}

private void populateOrRemovePreferences() {
    boolean hasTtsPrefs = populateOrRemoveTtsPrefs();
    if (!hasTtsPrefs) {
        // There were no TTS settings and no recognizer settings,
        // so it should be safe to hide the preference category
        // entirely.
        mFragment.getPreferenceScreen().removePreference(mVoiceCategory);
    }
}

private boolean populateOrRemoveTtsPrefs() {
    if (mTtsEngines.getEngines().isEmpty()) {
        mVoiceCategory.removePreference(mTtsSettingsPref);
        return false;
    }

    return true;
}

The removePreference call was crashing. Apparently, I had also uninstalled Google TTS, which was bundled with this version of Android.