Jani, thanks for the idea, some thoughts below your code.
> > class MyPublicationModel(Model): > def save(...): # I don't remember the signature > if self.is_published and not self.publication_date: > # Published previously unpublished - set the date > self.publication_date = date.today() > elif not self.is_published and self.publication_date: > # Mark already published as unpublished - clear the date > self.publication_date = None > > super(self, MyPublicationModel).save(...) > > Yes, you are right, but you are clearing the date, the thing is that I don't want to clear it. That's why I thought of having an attribute in the model that does not render in the form, that would allow me to keep the previous state unchanged and use that in my logic. > On Mon, Jul 16, 2012 at 3:39 AM, Nicolas Emiliani <or3s...@gmail.com>wrote: > >> >> >> On Sun, Jul 15, 2012 at 8:10 PM, Jani Tiainen <rede...@gmail.com> wrote: >> >>> Hi, >>> >>> How about telling us what are you trying to achieve by comparing to >>> previous state of the object? >>> >>> >> Well, the model has a boolean field called published, and a publish_date >> that gets set "automatically" >> when the user through the admin panel sets the flag published to true. He >> could also unpublish it, but the >> date would still remain the same (on the date it was first published). >> And here comes the problem : >> >> If the user decides to republish I would have to set the date to current >> date, but how do I know if he >> is republishing or he modified some other field that has nothing to do >> with that attribute ? I would be >> republishing only if it's previous state was not published. But how can I >> acces that previous state ? >> >> Sounds waky :P >> >> >> >>> On Sun, Jul 15, 2012 at 1:49 AM, Nicolas Emiliani <or3s...@gmail.com>wrote: >>> >>>> Hi, >>>> >>>> Is there a way to access the state of a Model object prior to it's >>>> modification through a form ? >>>> Kind of a nasty question :S, let me explain. >>>> >>>> The thing is that if i use the save_model hook and the user modifies >>>> the model through the form, >>>> the obj parameter that I receive has already all the modifications >>>> loaded, so if I have, let's say, >>>> a boolean attribute called "published" and the user clicked published >>>> then : >>>> >>>> obj.published == True >>>> >>>> Is there a way to know which was the state of the model, in this case >>>> the state of obj.published, >>>> before the user clicked on the save button on the admin form ? or >>>> should I use a second model >>>> attribute and hide it on the form to keep the previous state ? is there >>>> a "Django" way to do this ? >>>> >>>> It's my first post, be gentle :P >>>> >>>> Thanks ! >>>> >>>> -- >>>> Nicolas Emiliani >>>> >>>> Lo unico instantaneo en la vida es el cafe, y es bien feo. >>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "Django users" group. >>>> To post to this group, send email to django-users@googlegroups.com. >>>> To unsubscribe from this group, send email to >>>> django-users+unsubscr...@googlegroups.com. >>>> For more options, visit this group at >>>> http://groups.google.com/group/django-users?hl=en. >>>> >>> >>> >>> >>> -- >>> Jani Tiainen >>> >>> - Well planned is half done, and a half done has been sufficient >>> before... >>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "Django users" group. >>> To post to this group, send email to django-users@googlegroups.com. >>> To unsubscribe from this group, send email to >>> django-users+unsubscr...@googlegroups.com. >>> For more options, visit this group at >>> http://groups.google.com/group/django-users?hl=en. >>> >> >> >> >> -- >> Nicolas Emiliani >> >> Lo unico instantaneo en la vida es el cafe, y es bien feo. >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Django users" group. >> To post to this group, send email to django-users@googlegroups.com. >> To unsubscribe from this group, send email to >> django-users+unsubscr...@googlegroups.com. >> For more options, visit this group at >> http://groups.google.com/group/django-users?hl=en. >> > > > > -- > Jani Tiainen > > - Well planned is half done, and a half done has been sufficient before... > > -- > You received this message because you are subscribed to the Google Groups > "Django users" group. > To post to this group, send email to django-users@googlegroups.com. > To unsubscribe from this group, send email to > django-users+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/django-users?hl=en. > -- Nicolas Emiliani Lo unico instantaneo en la vida es el cafe, y es bien feo. -- You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com. To unsubscribe from this group, send email to django-users+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/django-users?hl=en.
