Hello,

I would like to suggest improvement to the function convertValues which is used in the virtualized datasources in multiple controls (dropdownlist, combobox, multiselect etc).

I've realised (after very long time) that the ValueMapper ajax is called in the initial loading, i.e. when there is no default value set in the control. In my opinion that request is extra unnecessary load and shouldn't happen if there is no value to be checked (mapped).

For example check this screenshot of the link https://demos.telerik.com/kendo-ui/dropdownlist/virtualization

In my code I started to surround with the following if:

if (options.value != "") {
        //value mapper code
    }
    else {
        options.success([])
    }

which stopped the initial value mapper ajax request.

This also helped to have only single value mapper request when there is default value set - otherwise it was generating 2 value mapper requests, one with empty value and another one with the set value.

I reckon this will help many users to improve their code.

Thanks.

Kind regards,

Kristina