When I use "listPreferences.setvalue()" the activity is created twice!! How to solve that?

Question

I'm working on android project that has an activity for app settings using "SharedPreferences" allowing user to select locale from list of locales.

When I use "listPreferences.setvalue()" to set the default selected value based on current Locale the SettingsActivity is created two times!!

The following is my code:

private void setLanguagePrefDefaultValues() {
    // Current Locale
    Locale sysLocale = getResources().getConfiguration().locale;
    // Language Preference
    ListPreference languagePref = (ListPreference) findPreference(getString(R.string.pref_language_key));
    // Edit Preference Summary
    languagePref.setSummary(sysLocale.getDisplayName(sysLocale));

    // Set Language Preference to Current Locale
    if (sysLocale.getCountry() != "") {
        languagePref.setValue(sysLocale.getLanguage() + "_" + sysLocale.getCountry());

    } else {
        languagePref.setValue(sysLocale.getLanguage());
    }
}

This methode is called from onCreate() method

I note that when "setSummary(...)" method is called there is no problem but the problem arises when the "setValue()" is called

The Settings Activity Class:

import java.util.Locale;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.res.Configuration;
import android.os.Bundle;
import android.preference.ListPreference;
import android.preference.Preference;
import android.preference.PreferenceActivity;
import android.preference.PreferenceCategory;
import android.view.View;
import android.view.Window;
import android.widget.TextView;
import com.telephoenic.simgateway.R;

/**
* Settings Activity
* 
* @author Abd Alrahman Shoman
* @since September 2013
* @version 1.0.0
* 
*/
public class SettingsActivity extends PreferenceActivity implements
    SharedPreferences.OnSharedPreferenceChangeListener {

public static boolean updatedLocale = false;

@Override
public void onCreate(Bundle savedInstanceState) {
    requestWindowFeature(Window.FEATURE_CUSTOM_TITLE);
    super.onCreate(savedInstanceState);
    addPreferencesFromResource(R.xml.settings_pref_file);
    getWindow().setFeatureInt(Window.FEATURE_CUSTOM_TITLE,
            R.layout.custom_title_bar);

    TextView title = (TextView) findViewById(R.id.textView_titleBar_title);
    title.setText(getResources()
            .getString(R.string.title_activity_settings));

    getPreferenceScreen().getSharedPreferences()
            .registerOnSharedPreferenceChangeListener(this);

    hideFirstLaunchPref();
    setLanguagePrefDefaultValues();
    setProfileEditPrefIntent();

}

@Override
protected void onStop() {
    super.onStop();
    getPreferenceScreen().getSharedPreferences()
            .unregisterOnSharedPreferenceChangeListener(this);
}

@Override
public void onSharedPreferenceChanged(SharedPreferences sharedPreferences,
        String key) {
    if (key.equals(getString(R.string.pref_language_key))) {
        Locale locale = null;
        String languageCode =     sharedPreferences.getString(getString(R.string.pref_language_key), "");
        if (languageCode.length() > 2) {
            char ch3 = languageCode.charAt(2);
            if (ch3 == '_') {
                String language = languageCode.substring(0, 2);
                String country = languageCode.substring(3, 5);
                locale = new Locale(language, country);
            }
        } else {
            locale = new Locale(languageCode);
        }

        Configuration config = new Configuration();
        config.locale = locale;
        getApplicationContext().getResources().updateConfiguration(config,
                getBaseContext().getResources().getDisplayMetrics());
        refresh();
        updatedLocale = true;
    }
}

/**
 * Hide FirstLaunchPref from preference screen
 * 
 */
private void hideFirstLaunchPref() {
    // First Launch Preference
    PreferenceCategory firstlaunchPref = (PreferenceCategory) findPreference(getString(R.string.pref_app_first_launch));
    // Hide First Launch Preference
    getPreferenceScreen().removePreference(firstlaunchPref);
}

/**
 * Set LanguagePref default Values (summary, selected language)
 * 
 */
private void setLanguagePrefDefaultValues() {
    // Current Locale
    Locale sysLocale = getResources().getConfiguration().locale;
    // Language Preference
    ListPreference languagePref = (ListPreference)   findPreference(getString(R.string.pref_language_key));
    // Edit Preference Summary
    languagePref.setSummary(sysLocale.getDisplayName(sysLocale));

    // Set Language Preference to Current Locale
    if (sysLocale.getCountry() != "") {
        languagePref.setValue(sysLocale.getLanguage() + "_" + sysLocale.getCountry());

    } else {
        languagePref.setValue(sysLocale.getLanguage());
    }
}

/**
 * Set ProfileEditPref Intent
 * 
 */
private void setProfileEditPrefIntent() {
    // Start PoS Profile Activity onClick
    Preference profile = (Preference) findPreference(getString(R.string.pref_profile_edit_key));
    profile.setIntent(new Intent(SettingsActivity.this,
            PosProfileActivity.class));
}

/**
 * Restart activity to reflect locale change
 * 
 */
private void refresh() {
    Intent intent = getIntent();
    overridePendingTransition(0, 0);
    intent.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
    finish();

    overridePendingTransition(0, 0);
    startActivity(intent);
}

/**
 * Back to previous activity
 * 
 * @param View
 *            v
 */
public void back(View v) {
    finish();
}

}

I am not sure what you mean by SettingsActivity is called twice. Btw for string comparison always use equals: sysLocale.getCountry().equals("") or sysLocale.getCountry().isEmpty() — cYrixmorten, Sep 29 '13 at 09:56
as far as I can tell your code never calls SettingsActivity, so I think you mean something else than you wrote in the title of your question. — cYrixmorten, Sep 29 '13 at 09:59
Thanks cYrixmorten for your advice about string comparison. "SettingsActivity" is the activity that responsible for creating preferences screen and "setLanguagePrefDefaultValues()" is called from its "onCreate()" method. I think "SettingsActivity" implicitly duplicated when I call "languagePref.setValue(...)" method such that I have to press back button twice if I want to get back to previous activity!! — Abd Alrahman Shoman, Sep 29 '13 at 13:10
That is weird. Cannot spot any reason why setLanguagePrefDefaultValues() should be responsible for this. Is SettingsActivity too big to add here to get the complete picture? — cYrixmorten, Sep 29 '13 at 13:14

score 0 · Answer 1 · edited May 23 '17 at 12:21

Try comment away your refresh() method.

onSharedPreferenceChanged will get called when you enter the SettingsActivity.

Also I do not see the need for this refresh() method.

If this does not work I will look more into it.

This must be the reason.. looked it over again:

@Override
public void onSharedPreferenceChanged(SharedPreferences sharedPreferences,
    String key) {
    if (key.equals(getString(R.string.pref_language_key))) {
       ... // this is called when setLanguagePrefDefaultValues() sets value
       refresh()
    }
}

private void refresh() {
    // start a new SettingsActivity, why you do this in the first place, I do not know 

    Intent intent = getIntent();
    overridePendingTransition(0, 0);
    intent.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
    finish();

    overridePendingTransition(0, 0);
    startActivity(intent);
}

Try rewriting your refresh method to:

private void refresh() {
    // ok it is to reflect the language update, i see :)

    Intent intent = getIntent();
    overridePendingTransition(0, 0);
    intent.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION | Intent.FLAG_ACTIVITY_NO_HISTORY);
    startActivity(intent);
    finish();

}

Otherwise see: [Removing an activity from the history stack

[1]: Removing an activity from the history stack for more options to remove current Activity from backstack.

actually the "refresh" method is for reflecting the locale change on the preferences screen once it's changed (redisplay the view with new locale). And I did comment it and yes you're right the problem didn't appear, but it disappear when you comment the "setValue(...)" and keep the "refresh" method. I'm sorry that I didn't mentioned that the problem appears just when the application runs for the first time(at first app launch) !!!. Thank you cYrixmorten I appreciate your concern — Abd Alrahman Shoman, Sep 29 '13 at 17:21
Ok now I better understand the reasoning behind it. Updated the answer. — cYrixmorten, Sep 29 '13 at 17:34

When I use "listPreferences.setvalue()" the activity is created twice!! How to solve that?

1 Answers1