Core Class Android


            package app.test;
import android.os.Bundle;
import android.preference.PreferenceActivity;
public class Test extends PreferenceActivity
{
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        addPreferencesFromResource(R.xml.main);
    }
}
//xml/main.xml

        xmlns:android="http://schemas.android.com/apk/res/android"
                android:key="using_categories_in_root_screen"
                android:title="Categories"
                android:summary="Using Preference Categories">
                    android:key="meats_category"
                android:title="Meats"
                android:summary="Preferences related to Meats">
                        android:key="fish_selection_pref"
                android:title="Fish"
                android:summary="Fish is great for the healthy" />
                        android:key="chicken_selection_pref"
                android:title="Chicken"
                android:summary="A common type of poultry" />
                        android:key="lamb_selection_pref"
                android:title="Lamb"
                android:summary="Lamb is a young sheep" />
    
                    android:key="vegi_category"
                android:title="Vegetables"
                android:summary="Preferences related to vegetable">
                        android:key="tomato_selection_pref"
                android:title="Tomato "
                android:summary="It's actually a fruit" />
                        android:key="potato_selection_pref"
                android:title="Potato"
                android:summaryOff="Yeah!"
                android:summaryOn="My favorite vegetable" />