How to add a delete button in the form edit

[Vu Hong Thuan]

Hi,
I want to create a delete button in the edit form .

<field name="submitButton" use-when="domainType==null"
title="${uiLabelMap.CommonCreate}"><submit button-type="button"/></field>
        <field name="submitButton" use-when="domainType!=null"
title="${uiLabelMap.CommonUpdate}"><submit button-type="button"/></field>
        <field name="submitButtonDelete" use-when="domainType!=null"
title="${uiLabelMap.CommonDelete}">
            <submit button-type="button"/>
        </field>

But, how to call to a delete service from the edit form. Normally, the edit
form includes 2 options: a call to insert service and a call to update
service.

<form name="EditDomainType" type="single" target="updateDomainType" title=""
default-map-name="domainType">
        <alt-target use-when="domainType==null" target="createDomainType"/>

How to insert a third option : call to delete service.