I'm using VB .Net 2010, ArcGIS 10.2.1I managed to capture if the AddIn dockable window had changed by hooking into the move event of the form.So went through the AddIN wizard to create a Dockable Window (in my case I called it dkwHotLink), exposed a property called UI so I could gain access to the controls on the form (there are several threads on this forum about that subject), added all the code I needed to for each control on the form and then added the Move event as shown below. If the form is moved it checks if it is floating, if so it resizes it. Private Sub dkwHotLink_Move(sender As Object, e As System.EventArgs) Handles Me.Move
Dim pdockWindowManager As IDockableWindowManager
pdockWindowManager = DirectCast(My.ArcMap.Application, IDockableWindowManager)
If Not pdockWindowManager Is Nothing Then
Dim pUID As UID = New UIDClass
pUID.Value = "GeoData_Institute_University_HER_AddIn_dkwHotLink"
Dim pDockableWindow As IDockableWindow
pDockableWindow = pdockWindowManager.GetDockableWindow(pUID)
If pDockableWindow.IsVisible Then
Dim pWindowPosition As IWindowPosition
pWindowPosition = pDockableWindow
If pWindowPosition.State = esriWindowState.esriWSFloating Then
pWindowPosition.Height = 560
pWindowPosition.Width = 349
Me.Refresh()
End If
End If
End If
End Sub
This code seems to fire when you dock/undock the dockable window but not when you are dragging it around.