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jwfv · Posted: Wed Mar 22, 2006 1:49 pm Post subject: @winexists

I have a program that removes one dialog element (a table) and replaces it with another when a certain button is pressed. I would like for that button code to be able to know when TableA is present or when TableB is present, so it can swap them out when the button is pressed again.

I thought that @winexists(~TableA) would let me know if it existed, but instead of it returning a null value, I get a runtime error. Here is code I used to test it:

WidgetCoder · Posted: Wed Mar 22, 2006 3:48 pm Post subject:

Apparently the "~" is an explicit reference and VDS assumes the element to be present.

Try:

jwfv · Posted: Wed Mar 22, 2006 5:05 pm Post subject:

That must be it. Thanks for the suggestion. I had thought of that, and may do something like that - but unfortunately, I am near the limit for the number of variables in my script! I reuse them when I can, but I don't have many to spare.

Thanks for the reply.

SnarlingSheep · Posted: Wed Mar 22, 2006 5:08 pm Post subject:

Nevermind.. if there is a dialog showing, it gives an unhandled exception.. pretty odd.

WidgetCoder · Posted: Wed Mar 22, 2006 5:47 pm Post subject:

jwfv · Posted: Wed Mar 22, 2006 6:27 pm Post subject:

I guess I could add a text dialog element with zero width and height, and set the text in it to identify which table was showing. Then using @dlgtext(), I can read the value.

WidgetCoder · Posted: Wed Mar 22, 2006 7:37 pm Post subject:

Try:

jwfv · Posted: Wed Mar 22, 2006 8:07 pm Post subject:

Interesting - thanks for the tip. When I tested your code a little further, I found that it just returns a really large number as the result of the @dlgpos() function (if that element doesn't exist). I wonder why that is? If it returned zero or something reliable, then we wouldn't have to compare it to the original position.

What I have done for now is use a 0x0 text element to hold the "toggle" value.

I also found that if I removed, then added, elements several times, I got a memory error. So instead I created both tables and then hid one of them. Then when they toggle, I just hide one and show the other. No errors.

Thanks for the feedback.

WidgetCoder · Posted: Wed Mar 22, 2006 8:18 pm Post subject:

jwfv · Posted: Wed Mar 22, 2006 8:33 pm Post subject:

You are right - I remember something about that. And I got the error from removing a table on a group element.

WidgetCoder · Posted: Wed Mar 22, 2006 9:21 pm Post subject:

I think the table issue most likely was just first noticed while using a tab control since you're constantly having to add and remove elements with a tab. The issue seems to have nothing in common with the use of a tab control itself but rather the act of removing a table directly. Apparently the table element isn't cleaning up after itself leaving pointers hanging to nonexistent memory.

I hope this issue gets resolved in v6! having to use a container to do the cleanup isn't the best workaround.

BTW: Your right about the @dlgpos issue, if the element doesn't exist it should change the @ok to null but doesn't. I tried using an "if @ok" statement first but it was always non-null since the function was returning errant number. I'd post this bug in the proper section if I thought for a second that someone at CR would actually read it.