How to create a new toolbar toggle button that toggles between Document Map view and Normal view

Our editors rely on a handful of toolbar buttons that were removed in Arbortext 7.  I have most of them replaced, but I still need to tweak one of them.

I've been digging through the Arbortext 7 Customizing Guide trying to figure out how to create a new toolbar toggle button that restores the Document Map button that toggles between Document Map view and Normal view.  I haven't found a solution yet and thought someone here might have done this already.  I currently have a button that shows the Document Map view, but in order to duplicate the functionality of the button as it existed in Arbortext 5, it needs to toggle between Document Map and Normal views.  Has anyone done that yet or know how to create such a button?

Here's one of the custom toolbars I assembled with the Document Map button first in the set:

<toolbar id="toolbar_Randy_Views" name="GC Views" x="50" y="25"><?Pub Dtl?>

<button command="ViewDocmap" id="Toolbar_Views_Randy"

image="imageDocumentMap" statustext="Document Map"

tiptext="Document Map"></button>

<button command="SyncOtherPane" id="Toolbar_Views_Randy"

image="imageSyncViews" statustext="Synchronize Views"

tiptext="Synchronize Views"></button>

<button command="WindowSplitLeft" id="Toolbar_Views_Randy"

image="imageLeftRightSplit" statustext="Left-Right Split"

tiptext="Left-Right Split"></button>

<button command="WindowSplitAbove" id="Toolbar_Views_Randy"

image="imageTopBottomSplit" statustext="Top-Bottom Split"

tiptext="Top-Bottom Split"></button>

</toolbar>