AutoCAD .NET API - 中断close pallete / window / user控制命令

Question

My first post, be gentle!

Im developing my own user controls for AutoCAD 2011 and cant for the life of me figure out how to interrupt the close on the User Control and insert my own functions before carrying on with the close.

Just for clarity here is a capture.

http://imgur.com/q1yDU

Basically before the window closes I need to clear a few of my own layers hidden behind the model space, because if the user can just close the tool and carry on without performing the wipe its going to cause issues eventually when it comes to adding new objects/saving/etc. I certainly cant trust a user to click a "Wipe" button on the UC before exiting, thats just asking for trouble.

So my question is: Where am I looking in the API for the code that closes the user control?

Answer 1

Acad palettes are not actually closed (disposed) when you click on the 'X' mark. They are just hidden. You might want to try the PaletteState::StateChanged event. It might be triggered when you 'close' the palette set. Just register a delegate for that event and see if it is called. Might work.

* EDIT * Now that I think more about it, you should be able to catch that event by registering a delegate to the Control.VisibleChanged event of your custom control. The one that you add as a child to the PaletteSet. That should work.

Answer 2

This is more of a comment than an answer, but I fear it will end up too big for a comment. Here's some food for thought. I'll try to be as gentle as I can but I'm not known among those who know me for my gentleness.... ;)

I'm worried that you're going about this in a... less-than-ideal way architecturally. Your question suggests that you want the user to perform a modal operation (command - show dialog - do stuff with dialog - close dialog) but you're using a modeless (potentially always on) GUI element (the PaletteSet ).

Have you asked yourself - what happens if the user never closes the dialog? With the PaletteSet they have that option. In that case your "wipe" will never run. Will that also cause problems down the road?

I guess the question I would encourage you to ask is "is the PaletteSet the right tool for the job I'm doing?" I'm only taking a guess at the job and work flow from your description and screen shot, but what I'm guessing concerns me. I wonder if what you really want to use here is a simple modal Form, launched from whatever mechanism currently launches your PaletteSet , that the user has to dismiss with an OK button, and then you would do your "wipe" in the OK handler.

If the reason you're using a PaletteSet is because the user has to interact with the drawing while it's active, there are ways to make a modal dialog get out of the way and allow them to pick entities or whatever it needs. Bear in mind that while a modeless PaletteSet is active the user can do literally anything else - open other drawings, draw entities, xref other drawings, run other commands, etc. Does your dialog need them to have that much flexibility? Is it prepared to handle itself properly in all those situations?

I hope this has been somehow helpful even if I completely misunderstand your situation.