问题
I would like to make a 2D iPhone game, I've done some research and Cocos2D does seem like the best option, I am just wondering how much knowledge of Objective-C I will need before tackling Cocos2D. I know the fundamentals of programming in Objective-C - I can make a basic command line tool app. I've done some iOS SDK tutorials but I wouldn't know how to make an iOS app if I was asked because the tutorials I'm currently following are about three years old.
What is required as prior learning before using Cocos2D and does anyone know of any good resources? I'm more of a visual learner so I find videos more helpful than books or blog posts.
Thank you in advance for your time and any help :)
回答1:
There is no required prior learning. Use it. If you get stuck on something, look it up, google it, or ask a question.
Meaning: don't waste your time learning general concepts without actually being in the situation of having to apply them.
Analogy: you don't need a PhD in mechanical engineering to drive a car - though it might help when you run into any issues. But in such a case just do what 99% of all people do: call for help. It hardly makes any sense to first learn the potential problems you can have with a car, you deal with them as they happen.
Also: frustration is part of the game and can not be avoided. :)
回答2:
how much knowledge of Objective-C I will need
A lot. You need to master Objective-C before trying to make a bigger project like this.
And to understand Objective-C, you need to have a very solid knowledge of C.
(Also, for using 3rd-party frameworks lile Cocos2D, make sure you understand well the basic, default libraries such as Foundation and UIKit.)
回答3:
For making games like Free flow , having an intermediate knowledge of Objective-C is sufficient. But if you plan on make something like Temple Run, then you need really good knowledge of Objective -C,Open-Gl and cocos2d..
The site I would recommend is raywenderlich.com, that's where i started from and they have tutorials from really basic level to really advanced level.
Hope this helps
回答4:
The answer to that depends truly on who you are, your work ethics, and how much effort your are ready to consent to that effort. I would argue that if you have solid foundations with other OO language/frameworks, your quest is possible. I would start by 'repurposing' a freely available game ( you will find many good examples and tutorials from Ray Wenderlich and also Steffen Itterheim. Pick a sample project that is not too 'distant' from your game specification, and repurpose it. In doing so, you will break-in to objective-C and some of the basic frameworks you need to comprehend. Mastery will follow if you are dedicated and stick to it. Also, SO rules : many answers are available here : appropriate questions will yield many helpful hints and solutions to point problems.
ps. My biggest learning curve turned out to be xCode, a truly arcane and dogma-ladden IDE. I since switched to another IDE and my productivity has gone back to respectable levels.
回答5:
I recently picked up Objective-C and cocos2d at the same time. I did a lot of reading about objective-c in the beginning to give me a primer. Aside from the syntax, most of that knowledge remains unused in my game. The most important things to learn about objective-c before starting in on cocos2d tutorials are, memory management, and debugging.
The reference count memory management might take a minute to get used to depending on what languages you are coming from. The general rule is, if you alloced/copied (without autorelease) or retained it, you must at some point release it, and if you need to use something beyond the current scope, you should retain it. You can see from some cocos2d examples of overwriting an objects dealloc method in order to dealloc anything you created/retained.
The debugging took me a minute to get used to as well. It helps if you add a high level try/catch block that you can use to log uncaught exceptions, otherwise some of your errors will give you little info to go on. You may also want to research/mess with some of your project settings to allow for better bug catching, such as enabling zombies. A big causer of crashes in objective-c is sending messages to already dealloced objects. Once you come across a badaccess error that you can't figure out, you will basically be forced to get knee deep in this stuff in order to figure out the cause.
Some other purely objective-c knowledge that will come in handy are getting very familiar with how NSArray and NSDictionary objects work, how they automatically retain/release, and how they can only hold objects (no primitive values). To work with floats/int and arrays/dictionaries, you need to convert primitives into something like an NSNumber object, which can be done fairly easily with a little research. Another helpful too is knowing how to save/load plists. There are convenience methods for doing this on NSArray and NSDictionary objects. This along with a little knowledge of the NSFileManager should be enough to help you save/load game states. If you want to get really fancy/clean in your coding, you will also learn about observers in objective-c. KVO can be great for making your UI update automatically on a certain objects property changes. For instance, my HUD KVOs the player object's life, so that when the life value changes, the HUD automatically updates. This can allow you to make a cleaner MVC type application. You can also register to listen to other types of messages (not just property changes), just make sure to unregister your listeners when you are done listening.
My last bit of advice would be to always pay attention to XCode warnings. If you are getting one, and you don't know why, you should figure out why. Some simple ones you might be able to ignore, others may cause bugs that you will not be able to track down any other way. For instance, I once used the function max() in my code, and xcode gave me a strange warning that I didn't understand. This caused havoc on my program by corrupting the stack. When I changed max() to MAX(), three or four unexplained bugs instantly disappeared. This kind of thing can set you back weeks, and take serious combing through every piece of your code if you don't catch it right away.
The rest can mostly be learned by looking at cocos2d code/examples. Good luck.
来源：https://stackoverflow.com/questions/14711268/requirements-for-learning-cocos2d