Save And Load User Preferences
Description
Android provides the SharedPreferences object to help you save simple application data.
Using the SharedPreferences object, you save the data you want through the use of name/value pairs.
In the following code, you learn how to use the SharedPreferences object to store application data.
Example
Create a file at res/xml/myapppreferences.xml and populate the myapppreferences.xml file as follows:
<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen
xmlns:android="http://schemas.android.com/apk/res/android">
<PreferenceCategory android:title="Category 1">
<CheckBoxPreference
android:title="Checkbox"
android:defaultValue="false"
android:summary="True or False"
android:key="checkboxPref" />
</PreferenceCategory>
<PreferenceCategory android:title="Category 2">
<EditTextPreference
android:summary="Enter a string"
android:defaultValue="[Enter a string here]"
android:title="Edit Text"
android:key="editTextPref" />
<RingtonePreference
android:summary="Select a ringtone"
android:title="Ringtones"
android:key="ringtonePref" />
<PreferenceScreen
android:title="Second Preference Screen"
android:summary= "Click here to go to the second Preference Screen"
android:key="secondPrefScreenPref" >
<EditTextPreference
android:summary="Enter a string"
android:title="Edit Text (second Screen)"
android:key="secondEditTextPref" />
</PreferenceScreen>
</PreferenceCategory>
</PreferenceScreen>
Java code
import android.os.Bundle;
import android.preference.PreferenceActivity;
//from w ww . j ava 2 s .c o m
public class AppPreferenceActivity extends PreferenceActivity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//load the preferences from an XML file
addPreferencesFromResource(R.xml.myapppreferences);
}
}
Note
Once you have modified the value of at least one of the preferences,
a file is created in the /data/data/com.java2s.your activity name/shared_prefs
folder of the Android emulator.