splitButton

In the object model this is RibbonSplitButton.
combines a button and a menu
you can either click the button or click on the menu
This is similar to the menu control in that it can include other controls
A SplitButton can be clicked directly and pushed as a button or its dropdown list can be displayed
It can also be configured to act list a togglebutton and have a toggled checked or unchecked state
Unlike the menu control the items cannot be changed dynamically at runtime
The buttons element cannot include a "size" attribute when they are inside a splitbutton.

<customUI xmlns="http://schemas.microsoft.com/office/2009/07/customui">

<ribbon startFromScratch="true">

<tabs>

<tab id="CustomTab" label="My Tab">

<group id="Group1" label="Group 1">

<splitButton id="MySplitButton1"

size="large">

<button id="Button1"

label="Normal Button with Menu"

imageMso="LeaveReader" />

<menu id="Menu1"

itemSize="normal" >

<button id="Button2" label="First" />

<button id="Button3" label="Second" />

<button id="Button4" label="Third" />

</menu>

</splitButton>

<splitButton id="MySplitButton2"

size="large">

<button id="Button5"

label="Large Button with Menu"

imageMso="LeaveReader" />

<menu id="Menu2"

itemSize="normal" >

<button id="Button6" label="First" />

<button id="Button7" label="Second" />

<button id="Button8" label="Third" />

</menu>

</splitButton>

</group>

</tab>

</tabs>

</ribbon>

</customUI>

Attributes (properties)

Children

This control can contain the following controls

C# Events (design-time)

The splitButton control has a Click event which can be accessed from the Visual Studio Ribbon Designer.
This event is the design-time equivalent of the Click event for its corresponding button.

Callbacks (run-time)