Adding listeners to individual ListPreference items

Question

I'm trying to add individual listeners to items in a ListPreference but I just can't find the right code to do it.

For example, assume I have an app where needs the region to be set. So I have a ListPreference with three options; Americas, Asia, Europe.

When I use the trackpad to scroll through the items I would like them to speak the text of the preference when they get focus.

I'm sure somewhere in the API I can add a listener to the individual items but I just can not find it. There is a setOnPreferenceClickListener(..) method in ListPreference (inherited from DialogPreference) but that is for when you select the actual parent preference item.

Do I need to write a special subclass?

EDIT

After looking into this more I think I need to further clarify my question. When using preferences you can override the onPreferenceTreeClick (PreferenceScreen prefScreen, Preference pref) method in the PreferenceActivity. This allows you to intercept any clicks on preferences. However I want to add a listener to the actual dialog that pops up. The "Americas, Asia, Europe" options from the above example. So if I select or click on Asia I can intercept it.

So my (refined) question is how can add a listener to those individual options.

cheers

score 10 · Answer 1 · edited Jul 25 '17 at 20:43

10

final ListPreference list = (ListPreference) preference;
list.setOnPreferenceChangeListener(new OnPreferenceChangeListener() {
    public boolean onPreferenceChange(Preference preference, Object newValue) {

        int index = list.findIndexOfValue(newValue.toString());

        if (index != -1) {
            Toast.makeText(getBaseContext(), list.getEntries()[index], Toast.LENGTH_LONG).show();
        }
        return true;
    }
});

edited Jul 25 '17 at 20:43

Phi

85
13

answered Jul 27 '14 at 21:15

fmgh

168
4
14

2

this doesn't solve the problem all the time. if user clicked on the default item this on change listener won't be called. – yongsunCN Jul 07 '16 at 15:21

score 2 · Answer 2 · answered Aug 07 '12 at 11:56

OnSharedPreferenceChangeListener is called when persistent = true after the sharedPref value was changed, but for each item you can actually assign its own OnPreferenceChangeListener and there you see which item was clicked

ListPreference pLocAuto = (ListPreference) findPreference(PREF_LOC_AUTO);
pUpdateAuto.setOnPreferenceChangeListener(new OnPreferenceChangeListener() {
            @Override
            public boolean onPreferenceChange(Preference preference, Object newValue) {
                System.out.print(newValue.toString());
                return false;
            }
        });

It helped, but it shall return TRUE if you want it to be saved after change. — careful7j, Feb 22 '17 at 23:16

score 0 · Answer 3 · edited May 23 '17 at 12:26

I think there's another post on stackoverflow that is similar to this one: Custom Row in a ListPreference.

In this one, subclassing is the solution. But may be in your case you can use a simple ListAdapter.

If you have set up the adapter, you can use the method onItemClick and inside the method you can use a switch statement (case is the id or the index in an array or anything like this) to call different methods.

I hope I understood your question... :)

Ah! You also need to have a look on the onFocusChange Listener. You can add this Listener to every Preference Item (which has to be a View; you add the listener in the adapter), then in the listener method have the announced switch statement.

Greetings and i hope i could provide you a hint,

Julian

Thanks Julian. I'm looking at that now. I'm still trying to get my head around `PreferenceScreen`, `ListPreference`, `ListView`, `ListAdapter` and how they all fit together. I basically need to get a reference to the `ListView` of my `ListPreference`. Is there a way to get a reference to a `ListPreference` (like the way you can do a `findViewByID(R.id.my_button)` )? — Tim, Feb 18 '11 at 00:01

Adding listeners to individual ListPreference items

3 Answers3

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