racket/collects/plot/common/snip.rkt

140 lines
5.7 KiB
Racket

#lang racket/base
(require racket/gui/base racket/class racket/list unstable/parameter-group
"math.rkt"
"parameters.rkt"
"plot-device.rkt")
(provide plot-snip%)
(define message-timeout 2000)
(define plot-snip%
(class image-snip%
(init bm)
(init-field saved-plot-parameters)
(inherit set-bitmap get-bitmap get-admin)
(super-make-object bm)
(define/override (copy) (make-object this% (get-bitmap) saved-plot-parameters))
(define/public (get-saved-plot-parameters) saved-plot-parameters)
(define x-mid (* 1/2 (send bm get-width)))
(define y-mid (* 1/2 (send bm get-height)))
(define/public (set-message-center new-x-mid new-y-mid)
(set! x-mid new-x-mid)
(set! y-mid new-y-mid))
(define/public (refresh)
;(printf "~a: refresh~n" (current-milliseconds))
(set-bitmap (get-bitmap)))
(define message #f)
(define message-timer (make-object timer% (λ () (stop-message))))
(define/public (stop-message)
;(printf "~a: stop-message~n" (current-milliseconds))
(send message-timer stop)
(set! message #f)
(refresh))
(define/public (reset-message-timeout)
(send message-timer start message-timeout #t))
(define/public (set-message msg #:refresh? [refresh? #t])
(define refresh? (and refresh? (not (equal? msg message))))
(set! message msg)
(reset-message-timeout)
(when refresh? (refresh)))
(define (draw-message dc dc-x-min dc-y-min)
(define bm (get-bitmap))
(define width (send bm get-width))
(define height (send bm get-height))
(define pd (make-object plot-device% dc dc-x-min dc-y-min width height))
(send pd reset-drawing-params #f)
(define lines (map (λ (line) (format " ~a " line)) (regexp-split "\n" message)))
(define-values (_1 char-height baseline _2) (send pd get-text-extent (first lines)))
(define line-widths (map (λ (line) (send pd get-text-width line)) lines))
(define box-x-size (apply max line-widths))
(define box-y-size (+ baseline (* (length lines) (+ char-height baseline))))
(define box-x-min (- x-mid (* 1/2 box-x-size)))
(define box-x-max (+ x-mid (* 1/2 box-x-size)))
(define box-y-min (- y-mid (* 1/2 box-y-size)))
(define box-y-max (+ y-mid (* 1/2 box-y-size)))
(define box-rect (vector (ivl box-x-min box-x-max) (ivl box-y-min box-y-max)))
;; inside selection
(send pd set-pen (plot-foreground) 1 'transparent)
(send pd set-brush (plot-background) 'solid)
(send pd set-alpha 1/4)
(send pd draw-rect box-rect)
;; selection border
(send pd set-minor-pen)
(send pd set-brush (plot-background) 'transparent)
(send pd set-alpha 3/4)
(send pd draw-rect box-rect)
(send pd set-alpha 1)
(for ([line (in-list lines)] [i (in-naturals)])
(send pd draw-text
line (vector box-x-min (+ box-y-min baseline (* i (+ char-height baseline))))
'top-left #:outline? #t))
(send pd restore-drawing-params))
(define/override (draw dc x y left top right bottom dx dy draw-caret)
;(printf "~a: drawing~n" (current-milliseconds))
(super draw dc x y left top right bottom dx dy draw-caret)
;(send dc draw-bitmap-section bm x y 0 0 width height)
(when message
(parameterize/group ([plot-parameters saved-plot-parameters])
(draw-message dc x y))))
(define left-down-admin #f)
(define/public (get-left-down-here?)
(eq? (get-admin) left-down-admin))
(send this set-flags (list* 'handles-events 'handles-all-mouse-events (send this get-flags)))
(define/override (on-event dc x y editorx editory evt)
(define admin (get-admin))
(define editor (send admin get-editor))
(case (send evt get-event-type)
;; The editor gives ownership to the snip as soon as the mouse left-clicks on it, before the
;; snip handles any events. On one hand, this is good: it means that mouse movement events are
;; sent to the snip even after the mouse leaves. On the other hand, it's bad: we don't want
;; the snip to *retain* ownership after the button is up, because it'll continue to hog all
;; the mouse movement events, keeping other plot snips from displaying hover messages. Also,
;; a plot snip has no selectable text, focusable controls, or any other reason to own the
;; caret.
;; So on left button up, if the left button went down on this snip, we give ownership to the
;; snip's editor.
[(left-down) (set! left-down-admin admin)]
[(left-up) (when (get-left-down-here?)
(set! left-down-admin #f)
(send editor set-caret-owner #f))]
;; The 'handles-events flag keeps the editor from handling right-click events, so the pop-up
;; menu won't pop up. So we call the editor's "local" event handler, which would have been
;; called had this snip not trapped events.
;; We also don't allow right/middle mouse clicks to transfer caret ownership, ever. We would
;; have similar rules to left-up, but the pop-up menu apparently gets right-up events, not
;; the snip.
[(right-down middle-down) (send editor set-caret-owner #f)
(send editor on-local-event evt)]
;; Just in case (we don't want these events anyway):
[(right-up middle-up) (send editor on-local-event evt)]
))
(define cross-cursor (make-object cursor% 'cross))
(define/override (adjust-cursor dc x y editorx editory evt) cross-cursor)
))