[Q] Difference between TkInterp and wish8.0

[Gary Polhill]

I've been trying to do some Tcl/Tk from inside Swarm, without much success.
As a Tcl/Tk newbie this is probably not much of a surprise. My Tcl/Tk book
mentions the tk_getOpenFile megawidget -- available from Tk8.0, and if I
run wish8.0 from my tk installation directory, I can do:

tk_getOpenFile -filetypes {{{LandParcel Files} {.lp}}}

and up pops a very nice file-opening dialogue box for opening a datafile
for my Swarm application (a simulation of rural land use decision-making).
(My plan was to attach this to a button from a ButtonPanel object or something.)

Inside ObserverSwarm, I have a method that calls:

  [globalTkInterp eval:
                    "tk_getOpenFile -filetypes {{{LandParcel Files} {.lp}}}"];

and when it gets there, I get the following error message:

(Tcl -eval:) no value given for parameter "specs" to "tclParseConfigSpec"
    while executing
"tclParseConfigSpec {__tk_filedialog {
        {-defaultextension "" "" ""}
        {-filetypes "" "" ""}
        {-initialdir "" "" ""}
    invoked from within
"unknown_pre_tclObjc $name $args"
    (procedure "unknown" line 6)
    invoked from within
"tclParseConfigSpec $w $specs "" $argList"
    (procedure "tkFDialog_Config" line 27)
    invoked from within
"tkFDialog_Config $w $type $args"
    (procedure "tk_getOpenFile" line 12)
    invoked from within
"tk_getOpenFile -filetypes {{{LandParcel Files} {.lp}}}"
while evaluating: tk_getOpenFile -filetypes {{{LandParcel Files} {.lp}}}
no value given for parameter "specs" to "tclParseConfigSpec"

I have no idea what to do to get round this -- if anyone has any
suggestions, I'd be very grateful.

More generally, what is the difference between running something from
TkInterp, and from wish8.0? What sort of Tcl/Tk commands can you run
from TkInterp succesfully, and what not? What caveats are there to
someone wanting to fiddle with the Swarm GUI? (E.g. I have a lot of
ZoomRasters -- how difficult would it be to amalgamate them onto one
window, that would select between the one displayed using a listbox
or buttons? Could a similar thing be done for EZGraphs?)

        Gary

-- 

Macaulay Land Use Research Institute, Craigiebuckler, Aberdeen. AB15 8QH
Tel: +44 (0) 1224 318611               Email: address@hidden

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