Italic text in Android ListPreference Summary

Question

I am creating a preference screen that has a few EditTextPreference and ListPreference attributes. I am trying to get the summary text to display " not set " when the preference is not set. Using etp.setSummary(Html.fromHtml("<i> not set </i>") works for EditTextPreference attributes but lp.setSummary(Html.fromHtml("<i> not set </i>") doesn't work for ListPreference attributes. The text "not set" is displayed but not in italics.

I have tried using the following to format the summary:

ListPreference lp = (ListPreference)findPreference("def_list_pref");
SpannableString str = SpannableString.valueOf("not set");
str.setSpan(new StyleSpan(Typeface.ITALIC), 0, str.length(), 0);
lp.setSummary(str);

and I've also tried manually setting the summary in preference.xml for ListPreference attributes to android:summary="<i> not set </i>" but that didn't work either.

Does anyone have any idea what I could be doing wrong or is this a bug with the ListPreference ?

Thanks.

Answer 1

public class SpannedSummaryListPreference extends ListPreference {

    private CharSequence mCharSequenceSummary;

    public SpannedSummaryListPreference(Context context) {
        this(context,null);
    }

    public SpannedSummaryListPreference(final Context context, final AttributeSet attrs) {
        super(context,attrs);
        mCharSequenceSummary = getSummary();
    }

    @Override
    public CharSequence getSummary() {
        final CharSequence entry = getEntry();
        if (super.getSummary() == null || entry == null) {
            return super.getSummary();
        } else {
            if (mCharSequenceSummary instanceof String) {
                return super.getSummary();
            } else {
                return mCharSequenceSummary;
            }
        }
    }

    @Override
    public void setSummary(CharSequence summary) {
        super.setSummary(summary);
        mCharSequenceSummary = summary;
    }
}`

---

EDIT: Kotlin solution:

class ListPreferenceEx @JvmOverloads constructor(context: Context, attrs: AttributeSet? = null) : ListPreference(context, attrs) {
    private var mCharSequenceSummary: CharSequence? = null

    init {
        mCharSequenceSummary = summary
    }

    override fun getSummary(): CharSequence? {
        val entry = entry
        val superSummary = super.getSummary()
        return if (superSummary == null || entry == null || mCharSequenceSummary is String)
            superSummary
        else
            mCharSequenceSummary
    }

    override fun setSummary(summary: CharSequence) {
        super.setSummary(summary)
        mCharSequenceSummary = summary
    }
}

Answer 2

Use Context#getText(int resId) to set summary text on your Preference programmatically :

findPreference("my_pref").setSummary(getText(R.string.settings_network_summary));

With your string resource formatted like this

<string name="html_string" ><u>underline</u> <i>italic</i> <b>bold</b></string>