Custom font for Preferences

Question

I used the code posted in this answer to try and set my preferences a different style (namely the font typeface and size), and it does indeed set the font properly. The problem with this code is, it extends the base Preference class, so I cannot create specific preferences (ListPreference, CheckboxPreference, etc.) and I'm stuck with basic preference objects, which I don't even know whether they have any proper use in terms of user interaction.

Now I could extend every Preference class I use to include the code in CustomPreference, but that seems like bad practice to me. Since there's no multiple inheritance in Java, is there any solution (perhaps any OO workaround) that can add this styling functionality to my CheckBoxPreferences, ListPreferences, PreferenceScreen, etc.?

Answer 1

You could use a Util-type class with public static methods. You'd have to extend each preference class you use still, but you could defer things like setStyleAlarmed to the Utils class instead of having the same code in each custom preference class.

public class PreferenceUtils {
    public static void onBindView(View view) {
        switch (style) {
            case STYLE_ALARMED:
                setStyleAlarmed(view);
                break;
            case STYLE_NORMAL:
                setStyleNormal(view);
                break;
            case STYLE_WARNING:
                setStyleWarning(view);
                break;
            //...
        }
    }

    // Move other methods here, e.g. setStyleAlarmed().
}

public class CustomPreference extends Preference implements PreferenceStyle {
    @Override
    protected void onBindView(View view) {
        super.onBindView(view);
        PreferenceUtils.onBindView(view);
    }
}