Android: preferences not being stored automatically
- by Vitaly
I'm trying to use preference screen. I'm following all steps from online tutorial (once I couldn't get it working, I found other tutorials, and steps seem to be fine). I get to preferences screen, edit values, return to calling activity (via hardware return button). In DDMS perspective FileExplorer shows package_name_preferences.xml file with preferences that should be stored. It contains:
<?xml version='1.0' encoding='utf-8' standalone='yes' ?>
<map>
<string name="false">kg</string>
</map>
while I expect (data line only shown).
<string name="weight">kg</string>
Also, if I go change only 1 preference, the same value changes, not a new row is created. I'm just tempted to write my own preference classes that would store data in files or DB, but I know that preferences should work, it just doesn't save properly my stuff.
Edit
Tutorials used:
Main Tutorial
- Was using this as a base, simplified, as I needed only 3 listPreferences so far.
Another One - Used this one back when first installed android, so referred to this one for its section on preferences
Code: (Screen loads, so I'm not showing Manifest)
public class MyPrefs extends PreferenceActivity {
@Override
public void onCreate(Bundle bundle) {
super.onCreate(bundle);
addPreferencesFromResource(R.xml.my_prefs);
}
}
my_prefs.xml
<PreferenceScreen
xmlns:android="http://schemas.android.com/apk/res/android">
<PreferenceCategory android:title="Value Settings">
<ListPreference android:title="Distance"
android:summary="Metric (Kilometer) vs Imperial (Imperial)"
android:defaultValue="km"
android:key="@+id/distanceMesurement"
android:entries="@array/distance"
android:entryValues="@array/distance_values"/>
<ListPreference android:title="Weight"
android:summary="Metric (Kilogram) vs Imperial (Pound)"
android:defaultValue="kg"
android:key="@+id/weightMesurement"
android:entries="@array/weight"
android:entryValues="@array/weight_values"/>
</PreferenceCategory>
</PreferenceScreen>
calling MyPrefs from MainScreen
Intent i = new Intent(MainScreen.this, MyPrefs.class);
startActivity(i);
arrays.xml
<resources>
<string-array name="weight">
<item name="kg">Kilogram (kg)</item>
<item name="lb">Pound (lb)</item>
</string-array>
<string-array name="weight_values">
<item name="kg">kg</item>
<item name="lb">lb</item>
</string-array>
<string-array name="distance">
<item name="km">Kilometer (km)</item>
<item name="mi">Mile (mi)</item>
</string-array>
<string-array name="distance_values">
<item name="km">km</item>
<item name="mi">mi</item>
</string-array>
</resources>
