How to access checkbox value in a settings activity from another activity?

I've created a new settings activity using the wizard in Eclipse. I would like to know how to access the value that reflects the user's choices. In particular, a checkbox option.

The code it has produced is as follows:

/src/com/example/myapp/SettingsActivity.java:

@Override
protected void onPostCreate(Bundle savedInstanceState) {
    super.onPostCreate(savedInstanceState);
    setupSimplePreferencesScreen();
}
private void setupSimplePreferencesScreen() {
    addPreferencesFromResource(R.xml.pref_general);
    //...
}

res/xml/pref_general.xml:

<CheckBoxPreference
    android:defaultValue="true"
    android:key="example_checkbox"
    android:summary="@string/pref_description_social_recommendations"
    android:title="@string/pref_title_social_recommendations" />

The wizard creates quite a large example, so I'm not sure if I've copied/pasted all the relevant code, but I have spent quite a long time and I'm pretty sure this is about it, (besides the string xml file).

How can I access the checkbox's value from another activity? I'm guessing I need to use a SharedPreferences object, but I don't know what keys I would use to access the data, as I can't find any constants in the code for that? Thanks