Watch when the View changes from Data View to Layout View

Question

I'm creating a dockable window add-in that requires the Active View to be the Data View.

I would like to disable my window when the user enters Layout View, but I've been unable to find an event that is triggered when the View changes.

I've attempted to us the "ActiveViewEvents" but none of them go off when switching views. And I know I can check if I'm in Layout view via:

IMxDocument doc = ArcMap.Document as IMxDocument;
if (doc.ActiveView is IPageLayout){/*disable window*/}
else {/*enable window*/}

but I'm at a loss on where to put this sort of check.

What event can I utilize to check when the users changes the View?

I want this event to be fired any time the user changes the view, and I do not want to put this check on every control.

and/or

Answer 1

Subscribing to view change event:

((ESRI.ArcGIS.ArcMapUI.IDocumentEvents_Event)ArcMap.Document).ActiveViewChanged += OnActiveViewChanged;

Handling view change event:

private void OnActiveViewChanged()
{
    if (((IMxDocument)ArcMap.Document).ActiveView is ESRI.ArcGIS.Carto.IPageLayout)
    {
        System.Diagnostics.Debug.Print("PAGE LAYOUT");
    }
    else
    {
        System.Diagnostics.Debug.Print("DATA LAYOUT");
    }
}