[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: how to find the TLB of a widget
- Subject: Re: how to find the TLB of a widget
- From: davidf(at)dfanning.com (David Fanning)
- Date: Wed, 22 Dec 1999 14:42:00 -0700
- Newsgroups: comp.lang.idl-pvwave
- Organization: Fanning Software Consulting
- References: <38613EC5.71E5AF2C@cornell.edu>
- Xref: news.doit.wisc.edu comp.lang.idl-pvwave:17844
Jonathan Joseph (firstname.lastname@example.org) writes:
> Is there a simple way (other than recursively getting the parent)
> to find the Top-level base of a widget. I don't have an event
> structure to query (which stores it as one of it's fields).
> It seems that it should be obtainable in one fell swoop using
> widget_info or widget_control, but I can't seem to find
> it if it is there.
> Shall I bother to write the routine get_tlb (OK, I've already
> written as it is so trivial) or does such already exist.
No event structure!? Weird.
Then why not pass it as a parameter into whatever program
needs the information.
IDL makes it trivially easy to pick out any widget in
a widget hierarchy by using the FIND_BY_UNAME keyword
to WIDGET_INFO. For example, you could define the widget
that carried your info structure (a label widget in this
case) like this:
infoCarrierID = Widget_Label(base, Value='Columns:', $
Then find it (usually) in any event handler like this:
infoCarrierID = Widget_Info(event.id, Find_By_UName='INFO_CARRIER')
This is particularly useful in compound widgets, where the
info structure cannot be stored in the top-level base.
David Fanning, Ph.D.
Fanning Software Consulting
Phone: 970-221-0438 E-Mail: email@example.com
Coyote's Guide to IDL Programming: http://www.dfanning.com/
Toll-Free IDL Book Orders: 1-888-461-0155