Thanks Fritz, a resource like that was what I was looking for - where I can I will always read Apple's documentation over examples/tutorials since they are often wrong or inaccurate. I will have a read tonight and see how I get on.
Sorry I wasn't more specific, I couldn't remember the name of the type - in the example I gave, region is indeed of type MKCoordinateRegion and myAnnotation extends NSObject and implements the MKAnnotation protocol i.e. @interface myAnnotation : NSObject<MKAnnotation> >From your comments I already understand it better - I thought the instance variable was also declared, not just the property. Therefore I will declare coordinate in the header, I won't declare a property and I will synthesize in the implementation. -Dan On 9 November 2010 15:18, Fritz Anderson <fri...@manoverboard.org> wrote: > On 9 Nov 2010, at 3:31 AM, Dan Hopwood wrote: > > > Ok so I am working with MKAnnotations on my map view and want to know the > * > > correct* (i.e. the Apple intended) way to set up my custom annotation > class > > so that I can set the coordinate upon initialisation but also access the > > coordinate attribute from outside the class e.g. in my case I wish to do > > something like: > > > > region.center = myAnnotation.coordinate; > > > > The above gives me an error and says the assignment is between > incompatible > > types. > > We need something better than "something like." Assuming "region" is an > MKCoordinateRegion, and "myAnnotation" implements MKAnnotation, the above > line is okay. But if "region" is your shorthand for "someMapView.region", > you have a problem. Show us the code. > > > I've done plenty of googling and have seen a few different solutions but > > none of which seemed to allow me to access the coordinate. Some people > > define a coordinate member variable and then @property/synthesize. > > Others named the member variable _coordinate and then *just* synthesized > it > > (not @property) using @synthesize _coordinate = coordinate; - I don't > fully > > understand what that means. Finally (in the case of the MapCallouts > source) > > others have defined a function called coordinate that returns the > > coordinate. > > <MKAnnotation> already declares @property coordinate, so there is no reason > to re-declare it. A -coordinate method, or a @synthesize if there is a > "coordinate" instance variable to back it, is enough. > > > If someone could give tell me the correct solution by means of a really > > simple example i.e. what should go in the .h and .m (I'm only interested > in > > the coordinate attribute for now) and then how to correctly access the > > coordinate attribute from outside the class for assignment e.g. the > center > > attribute of the region object (sorry I can't remember the exact name). > > Don't do this by Braille from what I can tell you off the top of my head, > or from cookbook examples. Read and understand for yourself the > documentation on properties at < > http://developer.apple.com/library/mac/#documentation/Cocoa/Conceptual/ObjectiveC/Articles/ocProperties.html > >. > > — F > > _______________________________________________ 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
