<dialog jcr:primaryType="cq:Dialog" title="Test Component" xtype="panel">
    <items jcr:primaryType="cq:WidgetCollection">
        <title jcr:primaryType="cq:Widget" fieldLabel="Selection" name="./sel" type="select" xtype="selection">
            <listeners jcr:primaryType="nt:unstructured" selectionchanged="function(comp, val, isChecked) {console.log("selected");}"/>
            <options jcr:primaryType="cq:WidgetCollection">
                <opt1 jcr:primaryType="nt:unstructured" text="Option 1" value="1"/>
            <opt2 jcr:primaryType="nt:unstructured" text="Option 2" value="2"/>
            <opt3 jcr:primaryType="nt:unstructured" text="Option 3" value="3"/>
            </options>
        </title>
        <link jcr:primaryType="cq:Widget" fieldLabel="Some Text" name="./text" xtype="textfield"/>
    </items>
</dialog>