> What's the actual difference between those two? I'm having trouble understanding what it is that you are asking.
handle() and callback() are very different beasts indeed. The handle() methods are used by the underlying fltk/OS system to propagate and "handle" window events (for the most part) whereas the callback() functions are attached to "user events", e.g. widgets being "pressed", timers firing, etc. Though you'd (generally) never call either in your own code, as the fltk core calls them at the appropriate times for you. > I want to know when some event occurs, the information is sent to FLTK > window, Which has two version of handle() and handle(int x) (I'm not > even sure what they do, just know they get/set the events). I am also > not sure that every widget also got the same handle() versions?. Hmm, this is all fairly standard C++ stuff (the business of there being "two versions of handle", and what widgets gets which handle method and so forth...) What languages are you experienced in? Maybe we can find a way to describe the mechanisms in terms you are more comfortable with? > Which > in turn calls the some other functions to call my call_back() to handle > the event which was set by my like FL_widget_mine->callback(Handle_it); Not quite, but sort of... The fltk core determines if (for example) the user clicks the mouse at some (x,y) position, if that position lies inside some button then the callback for that button will be invoked. But this mechanism is somewhat distinct from the handle() mechanism, so I'm not sure quite what you are getting at here... > I tried to read the manual two times but I wished I could sue the > company for creating such a problematic/hard to understand manual:( That'll not win you friends and influence people...! > .Can anyone share any good tutorial which explain overall working of it There's a few kicking around, including Greg's video tutorials and such, in particular try: http://www3.telus.net/public/robark/index.html and http://seriss.com/people/erco/fltk-videos/ (NOTE: Google is your friend...) SELEX Galileo Ltd Registered Office: Sigma House, Christopher Martin Road, Basildon, Essex SS14 3EL A company registered in England & Wales. Company no. 02426132 ******************************************************************** This email and any attachments are confidential to the intended recipient and may also be privileged. If you are not the intended recipient please delete it from your system and notify the sender. You should not copy it or use it for any purpose nor disclose or distribute its contents to any other person. ******************************************************************** _______________________________________________ fltk mailing list fltk@easysw.com http://lists.easysw.com/mailman/listinfo/fltk
