Placeholder should be hidden when a value is selected

[mvysny]

Hey Goran what's up? :-D

When you set a placeholder and the user selects a bunch of values, the placeholder should probably be hidden. That would be in line to ComboBox or TextField - if a value is selected or a text is typed, the placeholder is no longer shown.

This is the current behavior:

The following code reproduces the issue:

@Route("")
public class MainView extends VerticalLayout {

    public MainView() {
        final MultiselectComboBox<String> cb = new MultiselectComboBox<>();
        cb.setPlaceholder("Select a value");
        cb.setItems("1", "2", "3");
        add(cb);
    }
}

[gatanaso]

Hi @mvysny, thanks for reporting this issue :)

Could you please give it a try with the latest release candidate version 4.0.0-rc1 and let me know if this still happens?

Thanks.

[mvysny]

Hi Goran, sorry I was not able to test the addon. The minute I add multiselect-combo-box-flow to even a simple project, Vaadin crashes client-side with NotSupportedError: CustomElementRegistry.define: 'vaadin-lumo-styles' has already been defined as a custom element. I've tried both 4.0.0-rc1 and 4.0.0-rc2, plus Vaadin 23.0.0.beta2 🤔

[gatanaso]

Thanks for the feedback Martin. May I ask which version of Vaadin did you try with?

[mvysny]

Sure, thanks Goran, I tried Vaadin 23.0.0.beta1 and 23.0.0.beta2

[gatanaso]

Okay, thanks for the update 🙏 I haven't checked with Vaadin 23 yet, 22 has worked well so far at least.

[mvysny]

Oh, I'm sorry about that, I'll test with Vaadin 22, thank you :) I've filed the NotSupportedError as a separate ticket, let's ignore it here: #99

[mvysny]

Thank you, I've tested the component 4.0.0-rc2 with Vaadin 22 and indeed the placeholder is hidden. Thanks a ton for fixing this!