Filter the DataSource of the DropDownList Manually

Environment

Product	Progress® Kendo UI® DropDownList for jQuery
Operating System	Windows 10 64bit
Visual Studio Version	Visual Studio 2017
Preferred Language	JavaScript

Description

How can I manually filter the dataSource instance of the DropDownList?

Solution

The Kendo UI DropDownList has a built-in detection mechanism that checks whether the data is filtered or not.

The widget uses this information to decide when to persist the selected value that does not exist in the source. When the source is manually filtered, the widget loses the details about the state of the DataSource, which might lead to inconsistent behavior.

The following example demonstrates how to achieve the desired scenario.

<div id="example">
    <div class="demo-section k-header">
        <h4>DropDownList</h4>
        <select id="dropdownlist"></select>
    </div>
    <script>
        $(function() {
            var dropdownlist = $("#dropdownlist").kendoDropDownList({
                dataTextField: "name",
                dataValueField: "value",
                dataSource: {
                    data: [{ name: "One", value: 1 }, { name: "Two", value: 2 }]
                }
            }).data('kendoDropDownList');

            //Filter the source manually
            dropdownlist.dataSource.filter({
                field: 'value',
                operator: 'eq',
                value: 1
            });

            <!-- IMPORTANT: Update filter state of the widget -->
            dropdownlist.listView.setDSFilter(dropdownlist.dataSource.filter());

            dropdownlist.value(1);
        });
    </script>
</div>

See Also

• JavaScript API Reference of the DropDownList
• Automatically Adjust the Width of a DropDownList
• Create DropDownLists with Long Items
• Detect Wrapper Focus Events
• Move the Group Label on Top of Items
• Prevent Popup Closure on Scroll
• Remove Items
• Set DataSource Dynamically
• Update MVVM Bound Models on Load