Show/hide problem

J. Landman Gay jacque at
Thu Sep 20 21:35:34 EDT 2012

On 9/20/12 6:40 PM, Bob Sneidar wrote:
> What is the nature of the group you are showing or hiding? Is it a
> datagrid? It's my opinion that preOpenStack should be used only for
> things that need to happen before the stack opens. If it can be put
> into an openStack handler, put it there.

Maybe datagrids are a different beast, but I've never had trouble with 
preopencard. Its purpose is to allow us to set up everything before the 
card is drawn to screen, so that's what I use it for.

> If you are trying to show a
> group on a card in a preOpenCard or preOpenStack handler, technically
> the group doesn't exist in memory yet. (Someone will correct me if I
> am wrong).

Okay. :) I thought that too for 20 years, but it's wrong. I was 
corrected a couple of years ago by Mark Waddingham when I reported an 
erroneous bug against it.

Logic and intuition both told me that each message would fire 
sequentially as stack parts were loaded into memory. I operated on that 
assumption forever. Turns out it isn't true. The whole stack is loaded 
completely, THEN the messages are sent. To paraphrase Mark, "otherwise 
there wouldn't be any card to send the messages to."

Right. Duh. But then, I always feel a little stupid after talking with him.

> What I do if I do not want the end user to see a bunch of
> setup stuff like showing and hiding objects on a card, is I put a
> lock screen in the preOpenCard handler, then I do all my setup stuff
> in the openCard handler. As soon as all the scripts are done, the
> screen will automatically unlock and refresh.

Shouldn't be necessary. I never bother.

Jacqueline Landman Gay         |     jacque at
HyperActive Software           |

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