Changing display order in Outlook xml ribbon tabs

Is there a way to change the display order of a custom tab in an Outlook XML ribbon. I know it`s possible with the ribbon designer, but what about ribbons t开发者_如何学JAVAhat are designed in xml. Thanks

Use the "insertBeforeMso" or "insertAfterMso" attributes of the tab element.

<?xml version="1.0" encoding="UTF-8"?>
<customUI xmlns="http://schemas.microsoft.com/office/2009/07/customui" onLoad="Ribbon_Load">
  <ribbon>
    <tabs>
      <tab id="MyTab" visible="true" label="MyTab" insertBeforeMso="TabMail">
        <group label="MyGroup" id="MyGroup" autoScale="true">
          <button id="MyButton"
                  size="large"
                  label="Copy Excel Chart"
                  imageMso="HappyFace"
                  onAction="OnMyButtonClick"/>
        </group>
      </tab>
    </tabs>
  </ribbon>
</customUI>