On 3/16/12 2:00 PM, Brian Lambert wrote: > This means that my UILabel called labelMyLabel is publicly available. > Anyone who has access to an instance of MyViewController can do anything > they want to with my label, including replacing it. > > Also, anyone who has an instance of MyViewController can call my > buttonDoItTouchUpInside action.
In addition to David's remarks, it should also be noted that there isn't really any concept of "private" properties or methods (in the enforced sense) in Objective-C due to the dynamic nature of the language and runtime. No matter where you *declare* your properties and/or methods, what you state above would always be possible. (As an aside, major features in Cocoa rely on fairly crazy runtime manipulation. For example, key-value observing: http://mikeash.com/pyblog/friday-qa-2009-01-23.html) Suppose you wanted to peek under a class' hood (for curiosity's sake, of course; private API usage is generally a bad idea and is explicitly forbidden in the App Stores and from discussion on the official mailing lists). To see a class' properties (both from itself and its protocols) you could try something along the lines of (warning: a thrown together quick hack, probably has bugs): unsigned int propertyCount; objc_property_t *allProperties = class_copyPropertyList([MyClassName class], &propertyCount); for (NSUInteger i = 0; i < propertyCount; i++) { const char *name = property_getName(allProperties[i]); NSLog(@"%s", name); } unsigned int protocolCount; Protocol **allProtocols = class_copyProtocolList([MyClassName class], &protocolCount); for (NSUInteger i = 0; i < protocolCount; i++) { const char *protocol = protocol_getName(allProtocols[i]); NSLog(@"PROTOCOL %s", protocol); unsigned int protoPropertyCount; objc_property_t *protoProperties = protocol_copyPropertyList(allProtocols[i], &protoPropertyCount); for (NSUInteger j = 0; j < protoPropertyCount; j++) { const char *propName = property_getName(protoProperties[j]); NSLog(@"\t%s", propName); } } This and other fun hackery is documented in the Runtime Programming Guide: https://developer.apple.com/library/mac/#documentation/Cocoa/Conceptual/ObjCRuntimeGuide -- Conrad Shultz Synthetiq Solutions www.synthetiqsolutions.com _______________________________________________ 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: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
