Re: how to pass globals across modules (wxPython)
Fredrik Lundh, Tera 21 Dezembro 2004 16:33, wrote: well, in my applications, subsystems usually consists of one or more classes, or at least one or more functions. code that needs the global context usually gets the content either as a constructor argument, or as an argument to individual methods/functions. I see. Differences in terminology. We use the same approach as you do. Be seeing you, Godoy. -- http://mail.python.org/mailman/listinfo/python-list
Re: how to pass globals across modules (wxPython)
Peter Hansen, Segunda 20 Dezembro 2004 08:01, wrote: An even better approach might be to find a way to avoid having to access the main window through a global, but I'll have to leave this up to you, as it may depend on your program structure. This might be a problem also to share a database connection, where one needs to pass the open and authenticated connection to several specialized modules. Maybe a module where you can access that should be a better option... Be seeing you, Godoy. -- http://mail.python.org/mailman/listinfo/python-list
Re: how to pass globals across modules (wxPython)
Jorge Luiz Godoy Filho wrote: An even better approach might be to find a way to avoid having to access the main window through a global, but I'll have to leave this up to you, as it may depend on your program structure. This might be a problem also to share a database connection, where one needs to pass the open and authenticated connection to several specialized modules. Maybe a module where you can access that should be a better option... or a single application context class instance, which is passed to various parts of the system as necessary. making subsystems dependent on a module can hinder reuse; making them dependent on (parts of) the interface of an application context object makes them a lot easier to reuse. /F -- http://mail.python.org/mailman/listinfo/python-list
Re: how to pass globals across modules (wxPython)
Jorge Luiz Godoy Filho wrote: or a single application context class instance, which is passed to various parts of the system as necessary. Wouldn't that cause a chicken egg problem? How, then, would one pass such an instance across modules? well, in my applications, subsystems usually consists of one or more classes, or at least one or more functions. code that needs the global context usually gets the content either as a constructor argument, or as an argument to individual methods/functions. if you build a system by execfile'ing subcomponents (or importing them just to run their code, rather than use what they define), using this approach is harder. but that's not a very good way to build systems, so I'm not sure that matters... /F -- http://mail.python.org/mailman/listinfo/python-list
Re: how to pass globals across modules (wxPython)
I also struggled with this until I looked into many of the wxWindows examples. They all tend to pass in the parent to each subsequent layer of classes so that they can easily refer backwards in the hierarchy. Example In your code you will find that inside of SetTopWindow you have parent as the first argument. You can refer to parent.someattribute or parent.somemethod to refer back to application, which is instance of MainApp. Just do something similar in MainFrame class. Changing MainFrame class a little and passing in self as the first argument will give you the same ability inside of MainFrame instance. Something like: class MainFrame(wxFrame): def __init__(self, parentclass, parentframe): self.parentclass=parentclass wxFrame.__init__(self, parentframe, -1, Frame Description) . . . Then in Main App pass self as first argument (parentclass), then you can refer back to MainApp instance as self.parentclass. If you go several levels down you get self.parentclass.parentclass.parentclass.attribute: class MainApp(wxApp): def OnInit(self): self.mainFrame = MainFrame(self, None) self.mainFrame.Show() self.SetTopWindow(self.mainFrame) return True This might not be the best way, but seems to work and models what wxWindows appears to do internally. Larry Bates Syscon, Inc. Martin Drautzburg wrote: My wxPython program starts execution in mainFrame.py like this [...] class MainApp(wxApp): def OnInit(self): self.mainFrame = MainFrame(None) self.mainFrame.Show() self.SetTopWindow(self.mainFrame) return True def main(): global application application=MainApp(0) application.MainLoop() if __name__ == '__main__': main() I need to access the application object from other modules, actually the windows and frames that live therein and I don't know how to do this. I tried using global, but that does not seem to help. In the other module I run an import mainFrame and that seems to reset the global variables. Am I missing something obvious? -- http://mail.python.org/mailman/listinfo/python-list
Re: how to pass globals across modules (wxPython)
Martin Drautzburg wrote: My wxPython program starts execution in mainFrame.py like this [...] class MainApp(wxApp): def OnInit(self): self.mainFrame = MainFrame(None) self.mainFrame.Show() self.SetTopWindow(self.mainFrame) return True def main(): global application application=MainApp(0) application.MainLoop() if __name__ == '__main__': main() I need to access the application object from other modules, actually the windows and frames that live therein and I don't know how to do this. If you just need to access the running application from other wxPython objects, then wx.GetApp() is your friend. -- Hans Nowak http://zephyrfalcon.org/ -- http://mail.python.org/mailman/listinfo/python-list
