Thanks for the example. What I am looking for is slightly diferent. Lets say I have a entity called FavoriteWebsites with the attributes name and url. The current contents of the object are
Name | URL --------------------------------------------- Sam | http://www.aol.com Adam | http://www.digg.com Jane | http://www.ibm.com John | http://www.aol.com I want to filter for only the unique values of url, so the list I want to get back for a separate table is http://www.digg.com http://www.ibm.com http://www.aol.com Perhaps NSPredicate is not my answer and I just need to maintain a separate array and do some manual checking for duplicates. On Tue, Feb 26, 2008 at 7:20 PM, Philip Bridson <[EMAIL PROTECTED]> wrote: > Hi there, > > It will only return results from itself. > > Its like the classic example of employee and department. If you had a table > that you wanted to link to a list of employees you would bind to the > employee array controller and vice versa for the department one. You cannot > bind against the department controller for the value of, for example, > "Employee Name". All the predicate does is filters the list based on what > you want. e.g all employee with the name Joe. All you have to do is set the > exact predicate in the object that you are going to bind against: > > - (NSPredicate *)predicate > { > NSString *salaryLimit = @"10000"; > > NSPredicate *predicate = [NSPredicate predicateWithFormat @"salary > %@", > salaryLimit]; > > return predicate; > } > > Then when you bind your filter predicate to this method in your file owner > the array will only return objects that have a value of 10000 set in their > salary limit key. > > I hope I have been of assistance. > > Good luck, > > Phil. > > > > > On 27 Feb 2008, at 00:01, Adam Gerson wrote: > > I did look into NSPredicate and the Predicate Programming Guide. I > understand the concept of filtering the ArrayController. I just didn't > know how to write en expression asking for all unique values from the > ArrayController for a given key. In the Predicate examples they filter > a single potential result against some criteria. Can I say "only > return unique values from yourself"? > > > Adam > > > On Tue, Feb 26, 2008 at 6:03 PM, Philip Bridson > <[EMAIL PROTECTED]> wrote: > > > Yeah there is. > > From the documentation: > > > > You can set a predicate for an array controller to filter the content array. > You can set the predicate in code (using setFilterPredicate:). You can also > bind the array controller's filterPredicate binding to a method that returns > an NSPredicate object. The object that implements the method may be the > File's Owner or another controller object. If you change the predicate, > remember that you must do so in a key-value observing compliant way (see > Key-Value Observing Programming Guide) so that the array controller updates > itself accordingly. > > You can also bind the predicate binding of an NSSearchField object to the > filterPredicate of an array controller. A search field's predicate binding > is a multivalue binding, described in Binding Types. > > Or simply, create a small method in a object, such as the file owner, that > returns a NSPredicate. Then bind the controller's filter predicate to the > file owners predicate method. This will automatically filter your > controllers values. > > Hope this helps. > > Phil. > > On 26 Feb 2008, at 22:00, Adam Gerson wrote: > > > > I have a core data object. I would like to populate a TableView with > only the unique entires for a specific property. Clearly I could > filter the results in code, I was wondering if there was away for core > data and bindings to do it. > > Adam > _______________________________________________ > > 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/philipleebridson%40mac.com > > This email sent to [EMAIL PROTECTED] > > > _______________________________________________ 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 [EMAIL PROTECTED]
