Objective-C

Use@ Synchronized () indicates a synchronous method. The method for implementing synchronization is different from other language types by using a mutex lock. The locked object determines the size of the lock range. For example, the locked instance

1. Convert string to date Nsdateformatter * dateformat = [[nsdateformatter alloc] init]; // instantiate an nsdateformatter object[Dateformat setdateformat: @ "yyyy-mm-dd hh: mm: SS"]; // you can set the time format as needed.Nsdate * Date =

If the lifecycle of an object is obvious, it is easy to know when to use a new object and when it is no longer needed. In this case, you can use manual retain and release to determine whether a person is born or dead. However, sometimes it is not

1. for Chinese characters and some non-URL strings, use stringbyaddingpercentescapesusingencoding: Nsstring * escapedurlstring = [unescapedstring stringbyaddingpercentescapesusingencoding: nsasciistringencoding]; 2. The above method does not work

Uiwebview is one of the most commonly used sdks for iOS. It has a stringbyevaluatingjavascriptfromstring method that can embed Javascript into the page. Through this method, we can interact with webpage elements in uiwebview in IOS.

In objective-C, there are some data types that we are not familiar with but often see, such as ID, nil, nil, Sel, and so on. In many Article We have seen the introduction of these data types, but they are not clear. This article starts with the

1. the header file is still. h2. cpp is changed to. M.3. # import replaces # include, # import is guaranteed to be referenced only once, which is equivalent to # ifndef # define # endif mode in. h.4. Use @ interface... @ End to declare the class and

Since xcode 4.2, objective-C supports arc, which is a great boon for the majority of ipone developers. You don't have to face the ugly scenes like full screen [OBJ release] and [pool drain ].CodeMore importantly, you don't have to worry about the

Next, we will encapsulate the functions at the bottom, so that they can be used more conveniently. Code Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/--> Static Gbmusictrack * Track; Static

I recently developed the iPhone and used cocoa. I feel that the cocoa design is exquisite and the objecitive-C syntax is very simple and easy to use. Therefore, I want to check whether there is a runtime environment in windows, this makes it easy to

Basic Data Type   1. intOutput Format: % I, % d, % o % x, 2. FloatOutput Format: % F, % E, % G 3. DoubleOutput Format: % F, % E, % G 4. Char Output Format character: % C   Qualifier: 1. LongLong INT: % LiLong double: % lfTo form a long

Since multiple forms of source files can be written in objective-C, different file extensions can be used to differentiate them. Table 2-1 shows the file extension description: Table 2-1 Description of file extensions File Extension

If you want to learn objective-C, please pay attention to it. We recommend some learning materials for you and hope it will be useful to you !!! Getting startedArticle: Learn objective-C is very simpleLearn objective-C

In object-C, selector has two meanings: In the source file, it points to a method call, and after compilation it points to an unque indentifier. The type of the compiled selector is Sel, And the selector of the same name is the same. Using

** In the following content, interface refers to interfaces in the traditional sense, and @ interface refers to the type standard concept in objective-C to avoid confusion. It's a bit strange to see this chapter. In fact, you only need to know

The content of this series corresponds to the content described in the official objective-C language, which is divided into the following parts: Object, type, message Define a class Allocate and initialize memory for objects

  Nsarray _ sectiondatastr; _ sectiondatastr = [[nsarray alloc] region: [nsarray region: @ "Item1", @ "item2", nil], [nsarray arraywithobjects: @ "Item1 ", @ "item2", @ "item3", nil], [nsarray arraywithobjects: @ "Item1", @ "item2", @ "item3", @

Recently, a small application was developed to read Sina Weibo. The newly published Weibo posts on Weibo do not tell you when to release it, but tell you the time relative to the current time a few seconds ago, a few minutes ago, or a few hours ago.

Document directory Nsnumber Value assignment: Nsarray assignment and access: Nsdictionary assignment and access: New syntax features of objective-C 1. Improvement of enumeration types Previously, I declared that the enumeration method is

4. Cocoa memory management rules1) when you create an object using the new, alloc, and copy methods, the reserved counter value of this object is 1. when you no longer use this object, you are responsible for sending a release or autorelease message