V8 ComboBox with CallbackDataProvider problem

Vaadin 6 / 7 / 8
1

Hi!

I’m having a problem with combobox with CallbackDataProvider. It seems that CallbackDataProviders methods comes called twice everytime user enters a key in the combobox.

Example code that returns always 3 rows:

ComboBox<String> combo = new ComboBox<>();
CallbackDataProvider<String, String> dataProvider = new CallbackDataProvider<>(
                query -> {
                    LOG.debug("--QUERY-- " + query.getFilter().orElse(""));
                    List<String> test = new ArrayList<>();
                    test.add(query.getFilter().orElse(""));
                    test.add("AA");
                    test.add("BB");
                    return test.stream();
                },
                query -> {
                    LOG.debug("--COUNT--");
                    return 3;
                });
combo.setDataProvider(dataProvider);

When user enters “f” key, log looks this:

--QUERY-- f
--COUNT--
--QUERY-- f
--COUNT--

Am I missing something or is there bug in the framework?