February 2010 - ltk-user - mailman3.common-lisp.net

Re: [ltk-user] fix for ltk on mswin?
by dherring＠tentpost.com 22 Feb '10

22 Feb '10

Hi Peter, Thanks for getting back to LTK. > Hmm, Windows is strange :). But your explanation is the best I have heard for the windows problems so far... so I added > > #+mswindows (sleep 1) > > The waiting for a prompt has only one problem - tcl doesn't send a prompt > when run as a subprocess. I've poked at this a bit more; the sleep doesn't fix all my problems. It appears that incomplete commands are being flushed to wish and/or ltk is overflowing a stream buffer somewhere. For example, running ltktest with a trace on read-wish, I see errors like LTK::READ-WISH returned (:ERROR "value for \"-textvaria\" missing") or Error sending command to wish: on #<BASIC-CHARACTER-OUTPUT-STREAM ISO-8859-1 (PIPE/1092) #x8D5F2BE> : Invalid argument during write or LTK::READ-WISH returned (:ERROR "missing close-brace") This appears to be a race condition; the error changes randomly with each run (though the above are the most common). Sometimes the test almost works, other times it stops early. I did have to comment out the section which draws the lines -- that almost never worked. Similarly, theme-names generally fails (or whatever else does the first read-wish). For some reason, the situation can be aggravated by adding flush-wish in various places. But the first sleep at least lets Tk's window appear. - Daniel P.S. I'm debugging this in an attempt to get ABLE running.

3 6

[ltk-user] Greatly improved error/condition handling
by Thomas F. Burdick 22 Feb '10

22 Feb '10

I'm happy to announce that I (finally!) merged a new, greatly improved graphical condition handler into the repl branch. To take advantage of it, you don't need to do anything. By default, you'll get an error handler designed to be used by developers. If an error is signaled, you'll get a modal dialogue with the error message, plus a few buttons: * Dismiss will abort handling the Ltk event and go back to the main loop * Show Details will show you the stack trace. Not all lisps will actually get a stack trace here (SBCL and Allegro are privileged as usual), but patches are welcome :-) * Debugger will drop you into your system's debugger. If you're running Slime, this will be Slime's. Otherwise, you should probably look for a terminal. * Report Bug is a cool feature (if I say so myself). It pops up a bug reporter, which will save all the error information, including Ltk and CL version information, to a bug report file. For deployment to end users, you will probably want to to specify :DEBUG 1 to WITH-LTK (the default is 2). With this setting, you will simply see "An internal error has occured" and there will be no "Debugger" button. The bug report file should contain all the details you want from a bug report, though. :DEBUG 0 will do no condition handling, and leave everything to your Lisp implementation. :DEBUG 1 will use the PRODUCTION-CONDITION-HANDLER class :DEBUG 2 will use the GRAPHICAL-CONDITION-HANDLER class :DEBUG 3 will use the PARANOID-CONDITION-HANDLER class (it pops up a modal dialogue for /every/ condition signaled) Even better, the new graphical condition handling system is object-oriented and extensible. For example, you probably may want the bug reporter to send you an email. This is easy enough to add by subclassing PRODUCTION-CONDITION-HANDLER and writing a new REPORT-BUG method. The existing condition handler classes should be helpful as examples. To use your new condition handler, simply pass :DEBUGGER-CLASS MY-DEBUGGER-CLASS to WITH-LTK. Any feedback is welcome, and if you have bugs or questions, please ask them here. Voilà!

1 0

[ltk-user] [patch] Improved ttk treeview support
by Daniel Herring 19 Feb '10

19 Feb '10

Hi Peter, Please consider the attached patch against http://ltk.rplay.net/svn/branches/ltk/repl@215 It implements several essential treeview commands; they are being used to implement a symbol/package browser for ABLE. http://common-lisp.net/project/able/ The attached treeview-example.lisp demonstrates their usage. * (load "treeview-example.lisp") * (ltk-user::show-symbols :ltk-user) Thanks, Daniel

2 2

[ltk-user] fix for ltk on mswin?
by dherring＠tentpost.com 19 Feb '10

19 Feb '10

There have been many reports of ltk not starting properly on mswin boxes. I have an XP box that consistently shows this problem. The basic symptom is that when tk should appear, the active titlebar is grayed out but nothing else happens. When the lisp process is closed, the tk window full of ltk widgets appears. A few years ago, there were a couple reports on this list containing workarounds. However, I couldn't get any of them to work. After poking at this for a long time, I came up with the following patch. I can't guarantee 100% success, but it hasn't failed and it points to a possible obscure problem in ltk. ;; open subprocess (if (null (wish-stream *wish*)) (progn - (setf (wish-stream *wish*) (or stream (do-execute *wish-pathname* *wish-args*)) + (setf (wish-stream *wish*) (or stream (do-execute *wish-pathname* *wish-args*))) + (sleep 1) + (setf (wish-call-with-condition-handlers-function *wish*) (apply #'make-condition-handler-function keys)) ;; perform tcl initialisations Basically, it appears to me that due to scheduler timing, ltk may be writing to wish before it is ready, somehow causing the wish gui event loop to hang. The (sleep 1) is sketchy, but would it be hard to have ltk wait until it reads a wish prompt? ISTR there was a reason why this is a common pattern in expect. Thanks, Daniel P.S. Need... sleep....z.z.z.z.zzzzzzz

2 1