I was able to resolve the problem in Roassal using session management. Tx Kilon and Igor for your help.
Usman On Tue, Dec 3, 2013 at 3:58 PM, kilon alios <kilon.al...@gmail.com> wrote: > you dont have to wait for my example as i said checkSession is already the > example > > checkSession > session == Smalltalk session ifFalse: [ > "just reset the surface" > surface := nil. > session := Smalltalk session. > ] > > as you can see here essentially we compare session if they differ then we > know we need to reinitialize all our external resources in this example > surface . Not that it assigns surfaces as nil but you will need to fully > reinitialize the surface cause otherwise you will have a non existent > surface still. In this class a nill surface is reinitialized by another > method. > > Also I like to note here that Roassal Easel appear also not to check > sessions and exhibits the known problem if image is stored with Easel open. > Its something Roassal people would need to look at. > > > On Tue, Dec 3, 2013 at 4:51 PM, Usman Bhatti <usman.bha...@gmail.com>wrote: > >> >> >> >> On Tue, Dec 3, 2013 at 3:46 PM, kilon alios <kilon.al...@gmail.com>wrote: >> >>> You are correct but so is Igor. Managing external resources has to do >>> with VM and Nativeboost itself and not with Athens. This could happen with >>> any other library. >>> >>> Session aware code is actually very easy to do and its explained >>> Athens-Tutorial package in AthensViewMorph>>checkSession . Its just 2 lines >>> of code. >>> >>> In step2 method there is a relevant comment >>> >>> "IMPORTANT NOTE: >>> the surface which we will create at this step will be used in later >>> steps. >>> This means that if you resize the window (changing the view size), you >>> may need to recreate surface. >>> Also, since surface uses external resources, quitting an image and >>> restarting it, will also require to >>> create a new surface, because the one from previous session will be no >>> longer accessible. >>> " >>> >> >> Ok. Tx. That's very useful info. I'll have a look. >> >> >>> >>> but there is no mention to check the checkSession method for an example >>> how sessions can be handled. I think this deserves a separate step by >>> itself with a nice example. Igor you want me to give me commit rights to >>> Athens repo to add that myself ? >>> >> >> And if you add the example to Athens, please let me know. >> >> >>> >>> >>> On Tue, Dec 3, 2013 at 4:21 PM, Usman Bhatti <usman.bha...@gmail.com>wrote: >>> >>>> >>>> On Tue, Dec 3, 2013 at 2:29 PM, Igor Stasenko <siguc...@gmail.com>wrote: >>>> >>>>> >>>>> >>>>> >>>>> On 3 December 2013 14:18, Usman Bhatti <usman.bha...@gmail.com> wrote: >>>>> >>>>>> Igor, >>>>>> >>>>>> I had a look at Athens demo to understand how to manage sessions and >>>>>> surfaces because Roassal uses AthensSurface and there is a defensive >>>>>> mechanism in place in Roassal to initialize the surface in case it is not >>>>>> done. In the meantime, I have discovered that the red rectangle bug is >>>>>> present in Athens demos as well. >>>>>> >>>>>> So, to reproduce. >>>>>> AthensFlakeDemo new openInWorld >>>>>> save image >>>>>> open image >>>>>> >>>>> >>>>>> I tested in Moose 5.0. >>>>>> >>>>>> 1. Should I open a bug entry in Pharo? >>>>>> >>>>>> only if you intend to fix it. because this demo was not intended to >>>>> be 'fully featured, end-user compatible >>>>> and fool-proof demo'. it just a demo to show animation and discard it, >>>>> but if you insist this is a bug, >>>>> feel free to fix it. >>>>> >>>> >>>> Unfortunately, I wont have time for this. For me it would have been >>>> good, had Athens provided an example of session management as a good client >>>> so that example-oriented people like me could understand easily. Because, >>>> otherwise, I'll have to look at the code of NativeBoost and that adds to >>>> the level of complexity because I would do things with trial and error. >>>> >>>> >>>>> >>>>> >>>>>> 2. With my superficial knowledge of Athens, my guess is that the >>>>>> session management can be done in Athens so that Roassal (and other tools >>>>>> built on top of Athens) do not need to do it. May be it is the case >>>>>> already >>>>>> but the demos are not using it then. >>>>>> >>>>>> I disagree. >>>>> >>>> Because then, files can also open/close and delete themselves >>>>> automatically, so you will be left only to do reading and writing... >>>>> Resource management is an application-level responsibility, not >>>>> framework level. >>>>> I cannot predict in Athens, how often one wants to create/destroy or >>>>> (re)use surfaces, and therefore i cannot >>>>> create and dispose them when i see fit within framework. >>>>> Correct me if i wrong. >>>>> >>>> >>>> I think this doesn't compare to file handling because there are many >>>> types of operations possible on files and that are application-specific. >>>> Here resource management is actually exception-handling: I should not give >>>> to my client a surface that does not exist any more. Now, of course, if >>>> there is some application-level intelligence is involved, we cannot put >>>> that in the framework. >>>> >>>> But I would understand the absence of such a mechanism in the framework >>>> but then a tutorial should explain to novices/first-timers how to do it. >>>> >>>> Usman >>>> >>>> >>>> >>>> >>>>> >>>>> >>>>>> Usman >>>>>> >>>>>> >>>>>> >>>>>> On Mon, Dec 2, 2013 at 5:14 PM, Usman Bhatti >>>>>> <usman.bha...@gmail.com>wrote: >>>>>> >>>>>>> Hello Igor, >>>>>>> >>>>>>> Moose 5.0 is using Athens as default canvas for Roassal and we have >>>>>>> bug with Roassal that seems to be related to Athens. >>>>>>> http://code.google.com/p/moose-technology/issues/detail?id=1019 >>>>>>> >>>>>>> I think it is related to the fact that we create a surface in the OS >>>>>>> with Athens and once we quit the image, the surface is destroyed as >>>>>>> well. >>>>>>> So, when image is restarted with the visualization trying to use the >>>>>>> surface, we get the error. >>>>>>> >>>>>>> Could you point to what possibly can be done to avoid this error? >>>>>>> Merely checking the existence of an appropriate drawing surface in >>>>>>> Athens >>>>>>> every time visualization is drawn, would it suffice? >>>>>>> >>>>>>> regards, >>>>>>> >>>>>>> Usman >>>>>>> >>>>>> >>>>>> >>>>> >>>>> >>>>> -- >>>>> Best regards, >>>>> Igor Stasenko. >>>>> >>>> >>>> >>> >> >
