摘要： The self variable is present in all Objective-C methods. it is one of two hidden arguments passed to code that implements a method. The initial value of self is always the object that received the message that led to the method's execution.The other hidden argument is _cmd, which identifies the 阅读全文

摘要： Cocoa有3个framework组成1. Foundation: 所有的面向对象语言都会有一些标准结构: value , collection , String, dates, lists, thread等等.所有的这些都在Foundation framework里面(可以对比C++的STL)2. Appkit: 所有和用户界面相关的类都在这里. Windows,buttons,text field, event, drawing. 它还有个名字: ApplicationKit3. Core Data: Core Data可以方便的让你把你的对象存储成文件,或是从文件中加载你的对象. 阅读全文

摘要： Part 2 chapter 3 Two Stage patterns[[SomeClass alloc] init].Cocoa's NSObject base class provides two methods that allocate memory for new instances, +(id)alloc and +(id)allocWithZone:(NSZone *)aZone.The +alloc method is implemented to call the +allocWithZone: method specifying a default zone arg 阅读全文