answer files with filter

Richard Gaskin ambassador at fourthworld.com
Mon Aug 28 14:12:32 EDT 2006


Sarah Reichelt wrote:
> The "answer file" command usually gets me thoroughly confused, but
> this time, I'm not sure it is able to do what I want.
>
> I want to allow the user to select a text file, but it has to be a
> text file with a name like "Slot45.txt". The number will vary, but it
> has to start with "Slot" and have the ".txt".

As has been noted here, filtering for prefixes is a lot harder than 
filtering for suffixes.  The former is too prone to user error, while 
the latter is what the system expects.  "Go with the grain", as they say.

Mark Waddingham did an *excellent* reworking of the answer file command 
for v2.6.1, and since then it offer unprecedented flexibility which 
works on all platforms without branching statements -- from the Dictionary:

   Syntax
     answer file[s] prompt [with defaultPath] [with type types \
        [or type types ...]]  [titled windowTitle] [as sheet]

   Examples
    answer file "Select a file to delete:"
    answer files "Select the files you wish to process:"
    answer file "Input:" with "/Macintosh HD/"
    answer file (field "Prompt") with type "Revolution Stacks|rev|RSTK"
       -- shows stacks
    answer files "Select the images you wish to view:" with \
      type "JPEG Images|jpg|JPEG" \
      or type "GIF Images|gif|GIFf" \
      or type "All Images|jpg,gif|JPEG,GIFf"

So in your case you could support a suffix like "tsv" and ALSO support 
"txt" and all:

  answer files "Select a file:" with type "Tab-Separated|tsv|TEXT" \
    or type "Text Files|txt|TEXT" \
    or type "All Files"

This will present the user on any supported platform with a standard 
GetFile dialog with an option control at the top which lets them choose 
between filtering for Tab-Separated, Text Files, or All Files, with the 
first one ("Tab Separated") as the default.

I LOVE this new "answer file with type" option, and have been replacing 
all of my older "answer file" calls with this new form to allow smooth 
support on both Mac and Win without having to check the platform and 
using "...with filter..." or "...of type..." for each one separately.

Thank you Mark!

--
  Richard Gaskin
  Managing Editor, revJournal
  _______________________________________________________
  Rev tips, tutorials and more: http://www.revJournal.com



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