<?xml version='1.0' encoding='UTF-8'?>
<ui xmlns="http://www.intertrust.ru/schema/palette/tn-ui">
<form>
<!-- ... -->
<component>
<button name="{name}">
<action>
<custom>
<operation>
<handler-ref ref="{handler name}"/>
</operation>
</custom>
</action>
</button>
</component>
<!-- ... -->
</form>
</ui>