RE: Adding a button to all GP forms
Since you mention Modifier and System.Reflection, I assume you are looking to use .NET to do this?
I have tried for several years to add a button to a GP form without using Modifier, but so far, it has not been practical. A colleague and I developed a solution that would allow you to use VS Tools to add a custom .NET button on any GP window, but the prototype wasn't reliable enough. It is quite difficult to overlay a control on a GP window reliably--positioning, resolution, resizing, moving, etc. are challenging.
I believe David Musgrave may be looking to add some functionality to his Visual Studio Integration Toolkit that would allow for custom controls that could be added to Dex forms using .NET, and perhaps also creating custom windows using .NET. Those controls and windows could then be managed by .NET. But it requires a Dex intermediate layer to create those objects.
It would then be possible to add the controls onto GP windows using Reflection, and also capture events using Reflection. I have used Reflection with VS Tools AddIns to attach event handlers to multiple windows, and it works well.
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