Question

I have a sharedPreferences implementation where I store user preferences. When the user clicks “preferences” in menu, I open the standar editor to allow the user to change preferences. This is the code:

@Override
public boolean onOptionsItemSelected(MenuItem item) {

    switch (item.getItemId()) {
    case R.id.MENU_PREFERENCES:
        Intent intent = new Intent(context, PreferencesActivity.class);
        startActivity(intent);
        return true;
    case xx:
                ....
    }
    Toast.makeText(this, "ERROR: Bad menu item", Toast.LENGTH_SHORT).show();
    return true;
}

In PreferencesActivity.java I have:

public class PreferencesActivity extends PreferenceActivity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        addPreferencesFromResource(R.xml.preferences);
    }



}

My question is if can I have a variable in the preferences for internal use, I mean, that will not be showed to user when startActivity(intent)? how?

I suppose I must change something in preferences.xml but dont know exactly what….

thanks

EDIT: as requested, I paste xml:

<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android" >
    <PreferenceCategory>
        <ListPreference android:title="Pomodoro duration" android:key="pomodoro_duration" android:summary="Duration of each pomodoro" android:entryValues="@array/array_duration_values" android:defaultValue="25" android:entries="@array/array_duration"/><ListPreference android:key="short_break_duration" android:title="Short break duration" android:summary="Duration of break after each pomodoro" android:entryValues="@array/array_duration_values" android:entries="@array/array_duration" android:defaultValue="5"/>
        <ListPreference android:title="Long break interval" android:summary="Interval of the longer break" android:key="intervalos" android:entryValues="@array/interval_array_values" android:defaultValue="4" android:entries="@array/interval_array"/>
        <ListPreference android:defaultValue="20" android:title="Long break duration" android:summary="Duration of break after each pomodoro" android:key="long_break_duration" android:entries="@array/array_duration" android:entryValues="@array/array_duration_values"/><RingtonePreference android:title="Notification sound" android:ringtoneType="notification" android:summary="Tone that will sound after pomodoro ends" android:key="notification_tone" android:showDefault="true" android:showSilent="true"/>
        <ListPreference android:summary="Period used to calculate productivity" android:title="Calculus period" android:key="calculus_period" android:entryValues="@array/array_calculo_valores" android:entries="@array/array_calculo"/>
      </PreferenceCategory>

</PreferenceScreen>

When I inveke the standar UI to allow user to set this variables, I would like to hide one of them programmaticaly. Is possible?

Answer 1

If it is not in preferences.xml, it won’t be displayed, so just don’t add it there. You can use the SharedPreferences class to get/set preferences without displaying a UI. Something like:

SharedPreferences prefs = PreferenceManager
                .getDefaultSharedPreferences(context);
boolean flag = prefs.getBoolean("flag", false);