Preferences library is causing E/libc & E/Pref errors

Question

I'm building a weather app using MVVM and retrofit and i recently added a PreferencesFragmentCompat subclass to implement some user settings using the preferences lib. After doing so, my app won't run and i keep getting these few lines of errors :

2020-04-08 00:54:12.346 18079-18079/? E/de.flogaweathe: Unknown bits set in runtime_flags: 0x8000
2020-04-08 00:54:12.410 18079-18079/com.nesoinode.flogaweather E/libc: Access denied finding property "ro.vendor.df.effect.conflict"
2020-04-08 00:54:12.421 18079-18110/com.nesoinode.flogaweather E/Perf: Fail to get file list com.nesoinode.flogaweather
2020-04-08 00:54:12.421 18079-18110/com.nesoinode.flogaweather E/Perf: getFolderSize() : Exception_1 = java.lang.NullPointerException: Attempt to get length of null array
2020-04-08 00:54:12.421 18079-18110/com.nesoinode.flogaweather E/Perf: Fail to get file list oat
2020-04-08 00:54:12.422 18079-18110/com.nesoinode.flogaweather E/Perf: getFolderSize() : Exception_1 = java.lang.NullPointerException: Attempt to get length of null array

I've got no idea what these are and i can't find any specific answers on stack or google.There are no indications on what is causing the error so i can't figure out if i'm doing something wrong or if it is a library issue. Any ideas?

Here's the SettingsFragment where i'm adding the preferences from an xml resource file :

class SettingsFragment : PreferenceFragmentCompat() {
    override fun onCreatePreferences(savedInstanceState: Bundle?, rootKey: String?) {
        addPreferencesFromResource(R.xml.settings_prefs)
    }
}

And here's how i'm reading some values from the sharedPrefs:

class UnitProviderImpl(context: Context) : UnitProvider {

    private val appContext = context.applicationContext
    private val preferences:SharedPreferences
        get() = PreferenceManager.getDefaultSharedPreferences(appContext)

    override fun getUnitSystem(): String {
        val selectedUnitSystemName = preferences.getString(UNIT_SYSTEM_KEY,
            UnitSystem.SI.name.toLowerCase(Locale.ROOT))
        return selectedUnitSystemName!!
    }
}

Are you using androidx? If so are you using this library? implementation 'androidx.preference:preference:1.1.0' — OscarCreator, Apr 09 '20 at 06:34
@Ossy33 yes, i'm using androidX but i'm using this library `implementation 'androidx.preference:preference-ktx:1.1.0'` — Stelios Papamichail, Apr 09 '20 at 10:43

score 0 · Answer 1 · answered Apr 10 '20 at 10:47

I managed to figure out a solution to the issue after doing some more research. Firstly, i commented out all the code related to the preferences library (and the lib itself) and run the app again. The run was successful without any errors so that narrowed it down to the androidx.preference:preference-ktx:1.1.0 library itself since my code was reviewed and couldn't find any issues with it. Looking through the preference docs i figured i could try out a beta or alpha version that may have fixed this issue. And lo and behold, after using the androidx.preference:preference-ktx:1.1.0-beta01 beta version and uncommenting the relative code, everything worked once again.

Preferences library is causing E/libc & E/Pref errors

1 Answers1