To: lablgtk at kaba.or.jp
Subject: Event weirdness in canvas
From: Michael Welsh Duggan <md5i at cs.cmu.edu>
Date: Fri, 16 May 2003 08:33:32 -0400
Message-ID: <87he7vhy03.fsf at cs.cmu.edu>
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary="=-=-="
Sender: Michael Welsh Duggan <md5i at md5i.dsl.telerama.com>

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If you run the attached bit of lablgtk2 code, you get some really
weird behavior in regards to events.  

As one moves their cursor into and out of the square, one gets
perfectly normal enter and leave events.If one right-clicks in the
square, they get an ordinary button-press 3 event.  The weirdness
begins when one left clicks in the square.  When I do this, I get
three events: leave, enter, and then a button-press 1 event.  Does
anyone know if this weirdness is part of the current libgnomecanvas
(v2.2.0.2, from Debian Sid), or part of lablgtk2?


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Content-Disposition: attachment; filename=test.ml

open GnoCanvas

let ct = ref 0

let do_stuff window =
  let swindow = GBin.scrolled_window ~packing:window#add ()in
  let canvas = canvas ~aa:true ~packing:swindow#add () in
  let () = canvas#set_scroll_region ~x1:(-75.) ~y1:(-75.) ~x2:75. ~y2:75. in
  let grp = group canvas#root in
  let _ = rect ~x1:(-50.) ~y1:(-50.) ~x2:50. ~y2:50. ~fill_color:"red" grp in
  let tile_event = 
    function
	`ENTER_NOTIFY _ -> 
	  let () = prerr_string "Enter " in
	  let () = prerr_int !ct in
	  let () = prerr_newline () in
	  let () = ct := !ct + 1 in
	  true
      | `LEAVE_NOTIFY _ -> 
	  let () = prerr_string "Leave " in
	  let () = prerr_int !ct in
	  let () = prerr_newline () in
	  let () = ct := !ct + 1 in
	  true
      | `BUTTON_PRESS b ->
	  (match GdkEvent.Button.button b with
	    1 -> 
	      let () = prerr_string "B1 " in
	      let () = prerr_int !ct in
	      let () = prerr_newline () in
	      let () = ct := !ct + 1 in
	      true
	  | 3 -> 
	      let () = prerr_string "B3 " in
	      let () = prerr_int !ct in
	      let () = prerr_newline () in
	      let () = ct := !ct + 1 in
	      true
	  | _ -> false)
      | _ -> false in
  ignore (grp#connect#event tile_event) 

let main () =
  let window = GWindow.window ~width:300 ~height:300 () in
  let () = GtkBase.Widget.push_visual (Gdk.Rgb.get_visual ()) in
  let () = GtkBase.Widget.push_colormap (Gdk.Rgb.get_cmap ()) in
  let () = do_stuff window in
  let () = GtkBase.Widget.pop_visual () in
  let () = GtkBase.Widget.pop_colormap () in
  let _ = window#connect#destroy ~callback:GMain.Main.quit in
  let () = window#show () in
  GMain.Main.main ()

let _ = main ()

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-- 
Michael Welsh Duggan
(md5i@cs.cmu.edu)

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