Objective-C

1. Create a hello WorldProgram   1. Start xcode, file-> new project Select command line utility on the left and foundation tool on the right.   2. Compile and run Click build and go or command + R to compile and run the program.  

In objective-C, @ property is used to identify attributes (generally instance variables ). Use @ synthesize in the implementation file to identify the declared variables, so that the system can automatically generate the setting and obtaining

1. Category) The classification in object-C is a compilation method that allows us to expand a class by adding a method (but new instance variables cannot be added through category ), and we do not needCodeThis is similar to defining attributes

@ Interface => start to define a class. @ End => end     @ Implementation => class implementation @ End => end     # Import => reference header files   @ Property => Objective-C 2.0 syntax, defining an attribute   ID ID

Objective-CStudy NotesPreprocessingProgramIs the content to be introduced in this article, mainly introducesPreprocessing ProgramStatement usage,Preprocessing ProgramThe statement is marked. Let's take a look at the details. I. # define 1. More

In objective-C, the process for defining a singleton class is as follows: 1. Define a static class object. The initial value is nil. 2. In the factory method (generally named "sharedinstance" or "sharedmanager"), use allocwithzone only if

In objective-C, the cocatouch framework further encapsulates the native socket, that is, stream. Add cfnetwork framework Initialize socket Cfreadstreamref readstream; cfwritestreamref writestream; cfstreamcreatepairwithsockettohost (null,

1. Objective-C calls the js method. You only need to call the method that comes with uiwebview. [Webview stringbyevaluatingjavascriptfromstring: [nsstring stringwithformat: @ "gethtmlstring ('% @')", htmlstr]; 2. When JS calls the objective-C

  // Int code block int Mutl = 7; int (^ visenblock) (INT) = ^ (INT num) {return num * Mutl ;}; nslog (@ "% d ", visenblock (4); // nsstring code block void (^ visenprintstring) (nsstring * Str) = ^ (nsstring * Str) {nslog (@ "Print: % @", str) ;}

IOSDevelopmentObjective-CAndJavascript InteractionThe operation is the content to be introduced in this article. It mainly explains the usage of stringbyevaluatingjavascriptfromstring. It is very powerful and easy to use, through this, we can easily

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

Http://www.davidhamrick.com/2012/02/12/Adding-Properties-to-an-Objective-C-Category.html Let's say you have a category that needs to store some information. Unfortunately you can't add an instance variable, but you can add something called an

Example ~ To implement Interaction between JavaScript and objc How does one implement JavaScript to call an interface inside objc? I implemented it in this way. For example, an entry JS Function testclick (CMD, parameter1, parameter2) { Alert (1

In: argument is an input argument only and won't be referenced later Out: argument is an output argument only, used to return a value by reference Inout: argument is both an input and output argument Const: The (pointer) argument is constant

In addition to category, objective-C has an associative extension mechanism. Category is common and serves to extend some new methods to existing classes. So associative is something that category cannot do, and attributes can be extended. Official

The unique data types in objective-C are listed here: I. String In objective-C, A String constant is a string sequence enclosed by a pair of @ and a pair of quotation marks. For example, @ "China" and @ "objective-c" are all valid string constants.

Nsmutablestring common methods for modifying strings + (ID) stringwithcapacity: Size Create a string with the size -(ID) initwithcapacity: Size Initializes a string with the size -(Void) setstring:

After using objective-C language for iOS development for a period of time, I found my language base was relatively weak and began to make up for my shortcomings. I found that after using a language, I can look back at many of its principles to find

First, introduce the framework audiotool. -(ID) initwithpath :( nsstring *) path { uint32 size, maxpacketsize; char * cookie; int I; If (gthereisanactivetrack) { nslog (@ "*** warning *** gbmusictrack only plays one track at a time! You must

1. Category (categories are also called categories. Add methods for classes without source code (System Classes and others' classes) 1) Role Extends others' classes and can be used as an alternative to subclasses. Put the code of the same class