Re: help with a mouse events in scheme

[Bertrand Petit <plt-s@phoe.frmug.org>]

On Thu, May 31, 2001 at 04:47:10PM +0200, Claudio Gamberini wrote:
> hello, my porblem is to intercept the mouse click into a canvas

You can do something like this:

(define my-canvas%
  (class canvas% (frame) 
	 (override
	  (on-event
	   (lambda (event)
	     (let ((type (send event get-event-type)))
	       (cond
		((eq? type 'left-down)
		 ...)
		((eq? type 'left-up)
		 ...))))))
	 (sequence (super-init frame '(vscroll hscroll)))))

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