What do I need to do to listen to TableView row editor?

[Young]

I have a row editor. When a TextInput is double-clicked one of the cell,
it will be selected and a cursor will be blinking. So, it becomes
editable. I want to know what cell becomes editable with blinking
cursor. There should be a listener for it but I could not find in
TableViewRowEidtor or TextInput. The sample code is below.

<rowEditor>
  <content:TableViewRowEditor>
    <cellEditors>
      <marketName>
        <TextInput bxml:id="a" textKey="x" prompt="a"/> 
      </marketName>
      <orderDateString>
        <TextInput bxml:id="b" textKey="y" prompt="b"/> 
      </orderDateString>
    </cellEditors>                        
  </content:TableViewRowEditor>
</rowEditor>