Use Select Event

The following code shows how to use the select even to trigger a selected item in the combobox:
<script id="scriptInit" type="text/javascript">
        $(document).ready(function () {
            $("#tags").wijcombobox();
            $("#states").wijcombobox();
        });
    </script>
<h2>
    Select</h2>
<div class="main demo">
    <!-- Begin demo markup -->
    <div>
        <select id="states" onchange="$('#output').html('I live in ' + this.value + '!')">
            <option value="AL">Alabama</option>
            <option value="AK">Alaska</option>
            <option value="AZ">Arizona</option>
            <option value="AR">Arkansas</option>
            <option value="CA">California</option>
            <option value="CO">Colorado</option>
            <option value="CT">Connecticut</option>
            <option value="DE">Delaware</option>
            <option value="FL">Florida</option>
            <option value="GA">Georgia</option>
            <option value="HI">Hawaii</option>
            <option value="ID">Idaho</option>
            <option value="IL">Illinois</option>
            <option value="IN">Indiana</option>
            <option value="IA">Iowa</option>
            <option value="KS">Kansas</option>
            <option value="KY">Kentucky</option>
            <option value="LA">Louisiana</option>
            <option value="ME">Maine</option>
            <option value="MD">Maryland</option>
            <option value="MA">Massachusetts</option>
            <option value="MI">Michigan</option>
            <option value="MN">Minnesota</option>
            <option value="MS">Mississippi</option>
            <option value="MO">Missouri</option>
            <option value="MT">Montana</option>
            <option value="NE">Nebraska</option>
            <option value="NV">Nevada</option>
            <option value="NH">New Hampshire</option>
            <option value="NJ">New Jersey</option>
            <option value="NM">New Mexico</option>
            <option value="NY">New York</option>
            <option value="NC">North Carolina</option>
            <option value="ND">North Dakota</option>
            <option value="OH" selected="selected">Ohio</option>
            <option value="OK">Oklahoma</option>
            <option value="OR">Oregon</option>
            <option value="PA">Pennsylvania</option>
            <option value="RI">Rhode Island</option>
            <option value="SC">South Carolina</option>
            <option value="SD">South Dakota</option>
            <option value="TN">Tennessee</option>
            <option value="TX">Texas</option>
            <option value="UT">Utah</option>
            <option value="VT">Vermont</option>
            <option value="VA">Virginia</option>
            <option value="WA">Washington</option>
            <option value="WV">West Virginia</option>
            <option value="WI">Wisconsin</option>
            <option value="WY">Wyoming</option>
        </select>
    </div>
    <p>
        <label id="output">
            Please select.</label></p>
    <!-- End demo markup -->
    <div class="demo-options">
        <!-- Begin options markup -->
        <!-- End options markup -->
    </div>
</div>