I'm trying to create a useful snip that displays a different sub-snip
every second. I think I've overridden every method required to get a
"useful" snip, but nothing gets display in DrRacket and the functions
aren't called ever. Are there other methods that need to be
overridden?
The code is below...
Jay
#lang racket/base
(require (for-syntax racket/base)
racket/class
racket/function
racket/runtime-path
racket/snip)
(define reactive-snip%
(class* snip% ()
(init-field sub-snips)
(printf "Snips: ~a\n" sub-snips)
(define (the-snip)
(list-ref sub-snips
(modulo (current-seconds) (length sub-snips))))
(define-syntax-rule (delegate id)
(define/override (id . a)
(define some-snip (the-snip))
(printf "Delegating (~a ~a) to ~a\n"
'id a
some-snip)
(send/apply some-snip id a)))
(delegate get-extent)
(delegate draw)
(delegate get-text)
; set-unmodified or modified
(super-new)))
(define-runtime-path img1 '(lib "PLT-206-larval.png" "icons"))
(define-runtime-path img2 '(lib "PLT-206-mars.jpg" "icons"))
(define sub-snips
(map (curry make-object image-snip%)
(list img1 img2)))
(define x
(make-object
reactive-snip%
sub-snips))
sub-snips
x
--
Jay McCarthy <j...@cs.byu.edu>
Assistant Professor / Brigham Young University
http://faculty.cs.byu.edu/~jay
"The glory of God is Intelligence" - D&C 93
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