Navigating through Measures

I develop a plugin to make a short of analysis to a part of a score, showing in a new score the significant changes (modulations) in music. i need to navigate simultaneously through all staves and all voices of a part, and I need to know the moment where I pass from a Measure to the next.
In the plugin object model, the Measure object provides properties and methods related to graphical user interface, but there is no a property to show its number.
Is there any form to get it? Thanks