[Solved] Some problem with the combobox using the CascadeTo

[Julien]

Hi,

I'm trying to use the CascadeTo element, but I'm having some troubles to use it:

I'm having two combo box:

@(Html.Telerik().ComboBoxFor(model => model.IdPublication)
                                            .Name("IdPublication")
                                            .BindTo(new SelectList(Model.AvailablePublications, "Id", "Name"))
                                            .HighlightFirstMatch(true)
                                            .Filterable(filtering => filtering.FilterMode(AutoCompleteFilterMode.Contains))
                                            .Placeholder(LocalizationResources.Views.Composer.BaseInfoForm.SelectPublicationPlaceHolder)
                                            .CascadeTo("IdFormat")
                                            .SelectedIndex(0)
                                            .Enable(true)
                                        )

@(Html.Telerik().ComboBoxFor(model => model.IdFormat)
                                            .Name("IdFormat")
                                            .HighlightFirstMatch(true)
                                            .Filterable(filtering => filtering.FilterMode(AutoCompleteFilterMode.Contains))
                                            .Placeholder(LocalizationResources.Views.Composer.BaseInfoForm.SelectFormatPlaceHolder)
                                            .SelectedIndex(0)
                                            .DataBinding(binding => binding.Ajax().Select("_GetFormats", "Home", new { area="Composer"}))
                                            .Enable(false)
                                        )

Here are my questions/problems:

1. The second combo-box is loading when I'm selecting something in the first one, OK, but why does it calls also the _GetFormats methods when I'm typping something in the combo-box? I want to load only once the list of format, and then use it.
2. When I select something in the first combo-box, the second combobox loads and have the value/Text "0" selected? I don't know where it comes from? If I display the drop down list, I don't have this value in it
3. By default, I'm seeing my place holders, but how can I make that they are not selectable?
4. What is the option to don't accept a written text, that isn't in the list?(a dropdown list with the contains search of the combo box)

[Georgi Krustev]

Hello Julien,

 
Straight upto your questions:

#1: I tried to reproduce the depicted using this online demo, but to no avail. Let me know if I am missing something.

#2: The ComboBox component is designed to allow custom values along with the predefined ones. I believe that the combobox's value is set to "0" when there are no items and that is why the "0" is shown. I will need a simple test project, which replicates the problem. Thus I will be able to observe it locally (and the returned data) and advice you further.

#3: This is not supported. Placeholder functionality of the ComboBox adds item in the begining of the list.

#4: As I mentioned the ComboBox is desinged to allow custom values. In order to achieve your goal you will need to wire the change event and prevent entering of a custom values:

function onChange() {
    var combobox = $(this).data("tComboBox");

    if (combobox.value() && combobox.selectedIndex == -1) {
          //custom value is entered. Clear combobox value if needed.
    }
}

Kind regards,
Georgi Krustev
the Telerik team