Le 12 juin 2011 à 20:12, Martin Hewitson a écrit : > This is a question about choosing the correct design pattern for a particular > application. This application is generic enough that I can describe it by a > simple parent-child model. > > Suppose I have a model object Parent which contains an array of Child objects. > > Then I have a ParentView object and a corresponding ParentViewController. The > controller has a reference to the Parent and to the ParentView and so can act > as a data source for the view. So far, so good. > > What I'm unsure about is, how to deal with the children objects. I will, in > principle, have a ChildView. This raises some questions: > > 1) Should I have a ChildViewController class? > 2) Where do I keep the array of ChildView classes? In the ParentView? And how > do I ensure that each ChildView is associated with the appropriate Child > object? > 3) If I do have a ChildViewController class, where should I keep the array of > these? In the ParentViewController? > > I can see a complicated spagehti system arising here. Suppose I don't only > have a Parent-Child system, but a deeper tree (A contains an array of B, each > B contains an array of C, etc), how should one extend the scheme? > > I'm guessing this is a generic enough situation that there exists a > best-practice for handling it. For some reason, I can't arrive at it myself, > so far. Any hints, keywords or clues would be well received.
This sounds like a typical tree structure. The basic structure is: Node Node *parent NSArray *childNodes // contains instances of Node NodeView NodeView *parentView NSArray *childViews // contains instances of NodeView The Model takes this structure and so should the View. I would say that you should design a NodeController and then derive from that class to add a ParentNodeController. Joanna -- Joanna Carter Carter Consulting _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
