Objective-C

OC Method and file compilationFirst, OC method(i) Object methods(1) Object method with-opening as-(void) xx;(2) Object methods can only be called by object(3) The member variables of the current object can be accessed in the object method(4) Call

Objective-c objects, functions, and methods (the relationship of object, function, and method).In Objective-c, the function of the object is called "method"."Implementation" refers to what the iOS actually did when a method was called, that is, what

1 "Set method memory management related parametersRetain//release old value, retain new value (for OC pair image type)Assign//Direct Assignment (default parameter, for non-OC objects)Copy//release old value, copy new value2 "whether to generate

Find out who's Who's agent first (delegate)Define proxy protocols, naming conventions for protocol names: control class name + DelegateDefining proxy methodsProxy methods are generally defined as @optionalProxy method names begin with the control

1. An object-oriented person knows that self equals this,super equivalent to calling a method of the parent class2.self is a hidden parameter of the class, pointing to the class that is currently calling the method, and another hidden parameter is

单例类是一种特殊的类，在一个进程种只会存在一个该类的对象，在iOS应用中只会出现一个对象。这种设计模式在系统框架中许多地方都使用了，如NSFileManager、UIApplication等。">单例类是一种特殊的类，在一个进程种只会存在一个该类的对象，在iOS应用中只会出现一个对象。这种设计模式在系统框架中许多地方都使用了，如NSFileManager、UIApplication等。">A singleton class is a special class in which only

A dictionary is a collection of data that holds a mapping relationship (Key-value pairs). A key-value is considered an entry (Entry), and the dictionary is a container for storing key-value pairs.Features of the Dictionary classUnlike arrays,

The purpose of this article is to understand how NSAutoreleasePool is used in objective-c , andobjective-c 's foundation library is actually a run-level object system. Unlike general object languages, such as C++,java, objects, like COM or CORBA,

1. Why should I have a category? Extending on the basis of existing classes can be implemented using both inheritance and composition, but why does OC have to have categories like this?Consider a scenario where a dictionary is created, key is a

1. Memory Storage AreaC, C + + inside. Stack area: Stores temporary variables and objects. Heap Area: stores dynamically allocated objects. Static variable Store: stores static variables and constant objects.The memory storage area of OC is the same

 cocoapods A management tool for a objective-c third-party libraryCategory: Getting Started with iOS 2012-11-19 14:17 40945 people Read Reviews collection reports Directory (?) [+]Introduced:Third-party libraries are indispensable when

In Objective-c, we can use the numeric data types in C, int, float, long, and so on. They are all basic data types, not objects. That is, it is not possible to send messages to them. Then, there are times when you need to use these values as objects.

Constant Constant name Description M_pi Circumference rate (= π) M_pi_2 1/2 of the circumference rate (= π/2) M_pi_4 1/4 of the circumference rate (= π/4) M_1_pi =

// 1. 字典初始化、赋值方式1 NSMutableDictionary *m_dictionary = [[NSMutableDictionary alloc] initWithCapacity:0]; [m_dictionary setObject:@1 forKey:@"语文"]; [m_dictionary setObject:@2 forKey:@"数学"]; [m_dictionary setObject:@3 forKey:@"英语"]; //

// Nsvalue can convert the C type to an objective-C object, such as nsange, cgpoint, cgsize, cgrect, cgvector, uiedgeinsets, and uioffset nsange range = nsmakerange (0, 1 ); nsvalue * rangevalue = [nsvalue valuewithrange: range]; // nsvalue converts

@ Indicates the "objective-c" flag, proving that you are using the objective-C Language Objective-C language keyword, @ property and @ synthesize pair. Function:Let the compiler automatically write a method declaration with the same name as the

The code block is essentially similar to other variables. The difference is that the data stored in the code block is a function body. Using a code block, you can pass in the number of arguments and get the return value just like calling other

OC (objective-C for short) Based on the C language, an object-oriented syntax with the smallest scope is added (the most essential part of object-oriented is retained, and the content of OC is not much java, java does not have much content than C ++,

Using Arc can help us reduce the burden of memory management, especially for programmers who are familiar with Java. Recently, the cfobject and nsobject conversions were encountered when obtaining the local address book. Because arc cannot manage

In Objective-c, there is an int data type. Why do we need to use the numeric object NSNumber? This is because many classes (such as NSArray) require the use of objects, whereas int is not an object.NSNumber is a numeric object. We can use the