Re: Why self? (Was: Newbie: Referencing Objects)
Coming from a Flex/Flash background I will have to say that there is BIG differences between ActionScript 2.0 and 3.0. AS 3.0 is a powerful OOP language and AS 2.0 is not. That being said, the same object oriented principles do apply in ActionScript 3.0 the same as Obj-C and the Cocoa Framework. I would say a good tutorial/book on MVC structure would clear up some things. Also obj-c is not as forgiving as ActionScript syntax wise. I could see the difficulty coming from Flash IDE into Cocoa. I think the transition is a little easier for a Flex Developer. Many mx.controls.* UI classes are similar to Cocoa UI classes except instead of listening for events you have targets, selectors, and delegates. -- Siavash Ghamaty On Oct 27, 2008, at 8:40 PM, Graham Cox wrote: On 28 Oct 2008, at 2:30 pm, john fogg wrote: I come from coding in Actionscript (Flash) and there things are apparently quite different. FWIW, I tried to do some coding in Actionscript a few years ago after being immersed in C++ for many years and then Objective-C/ Cocoa for a few years. To say that it was an exercise in utter frustration is an understatement. As a programmer in these real languages I found AS to be really mickey-mouse. Others' opinions will no doubt vary but I suspect that if you know AS well, moving to what I call a real language is going to mean unlearning a huge heap of rubbish. Sorry, just my opinion. --Graham ___ 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/coldsweat%40gmail.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]
Re: Why self? (Was: Newbie: Referencing Objects)
Hi again! I'm still plucking along and any help is still greatly appreciated! Here is the deal: I create a subobject called mySubObject inside my main object myMainObject. Now I want to access myMainObject from within mySubObject. I'm still not sure what the ideal way to do this would be but I have gotten it to work somehow. Inside myMainObject I create a property and point it to self so it stores a reference to myMainObject. Inside mySubObject I cannot access this by writing [pointerToMainObject doMethod]; but it works when I write [self.pointerToMainObject doMethod]; Why? What difference does self make here? I'm still trying to wrap my head around all this stuff so please bear with me here. :-) ___ 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]
Re: Why self? (Was: Newbie: Referencing Objects)
On Oct 27, 2008, at 8:35 PM, john fogg wrote: Inside mySubObject I cannot access this by writing [pointerToMainObject doMethod]; but it works when I write [self.pointerToMainObject doMethod]; Why? What difference does self make here? Because the latter accesses the property of self, and the former doesn't. Assuming you're not developing exclusively for 64-bit (the 64- bit runtime supports properties without synthesis or implementations, IIRC), then using the original pointer variable in place of the former ought to work. Nick Zitzmann http://www.chronosnet.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: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to [EMAIL PROTECTED]
Re: Why self? (Was: Newbie: Referencing Objects)
I'm new to objective-C and cocoa also, I I don't know the answer to your specific question about self. However, seems that one way to do it would be to have the init of mySubObject have an initializer with argument, and you would then create it something like this: SubObject * mySubObject = [[SubObject alloc] initWithParent:self] This save puting a variable set to 'self' inside MainObject. Best, John V. On Tue, Oct 28, 2008 at 03:35:55AM +0100, john fogg wrote: Hi again! I'm still plucking along and any help is still greatly appreciated! Here is the deal: I create a subobject called mySubObject inside my main object myMainObject. Now I want to access myMainObject from within mySubObject. I'm still not sure what the ideal way to do this would be but I have gotten it to work somehow. Inside myMainObject I create a property and point it to self so it stores a reference to myMainObject. Inside mySubObject I cannot access this by writing [pointerToMainObject doMethod]; but it works when I write [self.pointerToMainObject doMethod]; Why? What difference does self make here? I'm still trying to wrap my head around all this stuff so please bear with me here. :-) ___ 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/velman%40cox.net 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]
Re: Why self? (Was: Newbie: Referencing Objects)
On Oct 27, 2008, at 9:35 PM, john fogg wrote: Here is the deal: I create a subobject called mySubObject inside my main object myMainObject. Now I want to access myMainObject from within mySubObject. Your terminology is a bit hard to follow. Part of the problem is that object's don't have names, they have addresses. Object pointer variables have names and can contain the addresses of objects. But the pointer isn't the object and the object isn't the pointer. Understanding this is important, since you seem to be foggy on how the two concepts interact. A pointer can change which object it's pointing to over time. An object may be pointed to by many different pointers, which will have different names. And you don't write code or define properties inside objects. You define them in (or for) classes. So, when you say I create a subobject called 'mySubObject' inside my main object 'myMainObject' I translate that to mean, that you have a pointer named myMainObject to an instance of some custom class. In the implementation of that class, there's a method, and in that method you create another object of some other(?) class and store its address into a pointer named mySubObject. mySubObject might be a local variable, an instance variable, or whatever. Now, what does within 'mySubObject' mean? I assume you mean within an instance method of the class of which mySubObject is an instance. OK. In the method of the first class -- the class of myMainObject; where you created mySubObject -- you can pass 'self' to mySubObject as a message parameter. It might be a parameter of the init message (- initWithOwner:, for example), or you might use a setter (e.g. - setOwner:). The second class -- the class of mySubObject -- would keep track of the owner in one of its instance variables, possibly called owner. Then, when it wanted to message its owner, it could do [owner someMethod] or owner.someProperty, etc. I'm still not sure what the ideal way to do this would be but I have gotten it to work somehow. Inside myMainObject I create a property and point it to self so it stores a reference to myMainObject. Is that a typo? You have created a property on an object which refers to itself? That doesn't make sense to me. (Again, the property isn't inside myMainObject. It's inside the class from which myMainObject was instantiated.) Inside mySubObject I cannot access this by writing [pointerToMainObject doMethod]; but it works when I write [self.pointerToMainObject doMethod]; Why? What difference does self make here? That doesn't seem sensible to me. However, without seeing the code in question, it's very hard to tell what might be happening. Seeing the code would also probably clarify what you're trying to say. Cheers, Ken ___ 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]
Re: Why self? (Was: Newbie: Referencing Objects)
Ken Thomases wrote me off-list. I don't know if this was deliberate (I guess not) but I'd rather not quote his mail here without his consent. Anyways the problem is fixed and I understand it all a whole lot better now. Big thanks to everybody and esp. Ken. You all are very nice people!! ___ 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]
Re: Why self? (Was: Newbie: Referencing Objects)
Hi Ken! Thank you for your long answer! It cleared up a lot of things for me. I come from coding in Actionscript (Flash) and there things are apparently quite different. Is it true that all instances I create live in memory on the same level? That they are all somehow equal? And that all relationships between them are only by pointers? Because in Actionscript you can have instances inside other object's instances and once you dealloc the containing instance all the other object's instances it contained die with it. Think Matryoshka puppets or something like that. On 10/28/08, Ken Thomases [EMAIL PROTECTED] wrote: Part of the problem is that object's don't have names, they have addresses. I see. So I can only access an instance from within some other instance if I always remember to pass along a pointer to it? But the pointer isn't the object and the object isn't the pointer. This is what I got wrong I guess. So, when you say I create a subobject called 'mySubObject' inside my main object 'myMainObject' I translate that to mean, that you have a pointer named myMainObject to an instance of some custom class. In the implementation of that class, there's a method, and in that method you create another object of some other(?) class and store its address into a pointer named mySubObject. mySubObject might be a local variable, an instance variable, or whatever. Now, what does within 'mySubObject' mean? I assume you mean within an instance method of the class of which mySubObject is an instance. Thank you. You translated correctly and explained it to me at the same time! :-) Your following explanation did the trick for me. Thank you again! Cheers, John. ___ 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]
Re: Why self? (Was: Newbie: Referencing Objects)
On 28 Oct 2008, at 2:30 pm, john fogg wrote: I come from coding in Actionscript (Flash) and there things are apparently quite different. FWIW, I tried to do some coding in Actionscript a few years ago after being immersed in C++ for many years and then Objective-C/Cocoa for a few years. To say that it was an exercise in utter frustration is an understatement. As a programmer in these real languages I found AS to be really mickey-mouse. Others' opinions will no doubt vary but I suspect that if you know AS well, moving to what I call a real language is going to mean unlearning a huge heap of rubbish. Sorry, just my opinion. --Graham ___ 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]
Re: Why self? (Was: Newbie: Referencing Objects)
Hi Graham! On 10/28/08, Graham Cox [EMAIL PROTECTED] wrote: FWIW, I tried to do some coding in Actionscript a few years ago after being immersed in C++ for many years and then Objective-C/Cocoa for a few years. To say that it was an exercise in utter frustration is an understatement. [...] I think I know how you feel. :-) And I share your opinion about Actionscript and (for me) Flash in general. I feel kinda spoiled by Actionscript but I'm unlearning now. :-)) ___ 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]
