Hi,
RadComboBox does not having direct way to set its height, not dropdown height.
It is required functionality because its height should be as per website design.

Example demo: https://demos.telerik.com/aspnet-ajax/combobox/examples/overview/defaultcs.aspx

And here's what JAWS sees:

Note the extra unlabeled "Button" following every combo box. This is confusing to the reader. They have no way to know that it is associated with the preceding field.

Additionally, I've noted that when aria-support is turned on, this button becomes focusable. Tabindex="0" is added to the span inside the text box. We prefer the older functionality where the button was not a tab stop. Which is the same behavior you have when aria support is turned off. For reference, see your own aria demo:

• https://demos.telerik.com/aspnet-ajax/combobox/examples/wai-aria-support/defaultvb.aspx?show-source=true

Note that the tab key stops on the drop down arrow. (You can check the previously linked demo and see that the arrows in those boxes are not tab stops.)

If right-click the arrow and inspect, you'll find the following: 

<span id="ctl00_ContentPlaceholder1_RadComboBox2_Arrow" class="p-icon p-i-arrow-60-down" role="button" aria-controls="ctl00_ContentPlaceholder1_RadComboBox2_listbox" tabindex="0"></span>

Adding aria support should not change behavior, so we'd prefer the tab stop was removed.

In our own application, we have additional problems when the button is focused and activated with either the "space" or "enter" keys, it refocuses the field, but it does not actually open the drop down. I do not see that problem in your demo. However, if the arrow button was removed as a tab stop and from the INS+F5 dialog, this would not be a problem.

Please note that all of the above is in Chrome. 

Workaround: 

Using the following code in the OnClientLoad event of the ComboBox:

  var _DropDown_OnClientLoad = function (sender, args) {
    var input = sender.get_inputDomElement();

    //Remove tabindex from down-arrow button. We never want to focus this button.
    $telerik.$(input).siblings("button").find("[role=button]").attr("tabindex", null);

    //hide the down-arrow button from screen readers. The entire combo box
    //should be considered a single control.
    $telerik.$(input).siblings("button").attr("aria-hidden", "true");
}

The ComboBox pop-up is moving over the page during scrolling in mobile Chrome (Android device). The problem is occurres both in scrolled or zoomed elements.

*The same issue is reproducible also in the SkinChooser.

Steps to reproduce:
1. Run the following code in in mobile Chrome:
        <telerik:RadSkinManager ID="RadSkinManager1" runat="server" ShowChooser="true" PersistenceMode="ViewState" RenderMode="Auto" Skin="Telerik">
        </telerik:RadSkinManager><br /><br />
        <telerik:RadComboBox ID="cb1" runat="server" AutoPostBack="true">
            <Items>
                <telerik:RadComboBoxItem Text="January" Value="1" />
                <telerik:RadComboBoxItem Text="February" Value="2" />
                <telerik:RadComboBoxItem Text="March" Value="3" />
                <telerik:RadComboBoxItem Text="April" Value="4" />
                <telerik:RadComboBoxItem Text="May" Value="5" />
                <telerik:RadComboBoxItem Text="June" Value="6" />
                <telerik:RadComboBoxItem Text="July" Value="7" />
            </Items>
        </telerik:RadComboBox>

2. Tap over the combo in order to show its dropdown

3. Drag to scroll the page to the left


Result: The dropdown pop-up is moving over the page.

Given a RadComboBox with search, if the user enters some search text and then clicks on one of the filtered entries in the dropdown list the validation event is fired as the entry box loses focus and results in a 'false' return from validation as it uses the 'Text' property which is the search string. Validation is then refired as a result of clicking on the entry.
However, the initial 'false' return can cause unwanted behaviour in code that depends on the validation event.
I can supply a sample project demonstrating the problem, but it needs more than the 10 MB upload limit.

Reproduction: https://demos.telerik.com/aspnet-ajax/combobox/examples/wai-aria-support/defaultcs.aspx

1) focus the ComboBox

2) press C 

Expected: 

- Camembert Pierrot is selected

- JAWS pronounces "c" and "Camembert Pierrot"

Actual: 

- Camembert Pierrot is selected

- JAWS pronounces "c"

Reference for expected behavior: https://www.w3.org/TR/wai-aria-practices/examples/listbox/listbox-collapsible.html

Hi Telerik Support,

How do I move loading box to bottom of the combo box list when using load on demand feature. the case is we're using ShowMoreResultsBox=true and EnableVirtualScrolling=true and trying to get next batch of data on a heavy query, the loading box not showing on the list see image (2020-12-03 14_31_40-Agent - Verint Express.png).

can we show the loading box on the bottom of the dropdownlist, so user is aware that the data still being loaded.

Thank you

In WebService binding scenario, the text of the items is not encoded and HTML code might get executed. 

In Server-side Load on Demand binding this is not observed. 

The following code can be used as a temporary workaround for WebService binding scenario: 

<script type="text/javascript">
    Telerik.Web.UI.RadComboBoxItem.prototype._renderItemContent = function (d) {
        if (this.get_imageUrl()) {
            this._renderImage(d);
        }

        //https://stackoverflow.com/questions/6234773/can-i-escape-html-special-chars-in-javascript
        function escapeHtml(unsafe) {
            return unsafe
                    .replace(/&/g, "&amp;")
                    .replace(/</g, "&lt;")
                    .replace(/>/g, "&gt;")
                    .replace(/"/g, "&quot;")
                    .replace(/'/g, "&#039;");
        }

        d[d.length] = escapeHtml(this.get_text());
    }
</script>

Hi,

This is a follow on request from a ticket raised where it was stated this feature isn't available and there is no work around.

When you hook a RadCombobox to a RadClientDataSource, which returns a paginated set of results along with a count of total number of records, the RadCombobox should display the "Show More Results" box along with the text stating "Items 1 - x of y" as all that information should be able to be calculated from the data returned.

Currently, the behavior on selection is to highlight the selected item, so modifying the appearance of a selected item would affect the appearance of hovered items as well.

In the meantime, a custom CSS class can be added/removed to the selected item as in the snippet below:

<script>
    function OnClientLoad(sender, args) {
        var selectedItem = sender.get_selectedItem();
        if (selectedItem) {
            $telerik.$(selectedItem.get_element()).addClass("rcbSelected");
        }
    }

    function OnClientSelectedIndexChanged(sender, args) {
        $telerik.$(sender.get_dropDownElement()).find(".rcbSelected").removeClass("rcbSelected");
        var selectedItem = sender.get_selectedItem();
        if (selectedItem) {
            $telerik.$(selectedItem.get_element()).addClass("rcbSelected");
        }
    }
</script>

<style>
    div.RadComboBoxDropDown .rcbSelected {
        color: red;
        background-color: lightgreen;
    }
</style>
<telerik:RadComboBox ID="RadComboBox1" runat="server" RenderMode="Lightweight" OnClientSelectedIndexChanged="OnClientSelectedIndexChanged" OnClientLoad="OnClientLoad" MaxHeight="150">
    <Items>
        <telerik:RadComboBoxItem Text="Item 1" />
        <telerik:RadComboBoxItem Text="Item 2" />
        <telerik:RadComboBoxItem Text="Item 3" Selected="true" />
        <telerik:RadComboBoxItem Text="Item 4" />
    </Items>
</telerik:RadComboBox>