Objective-C

   [receiver message];

   [myRect setOrigin:30.0 :50.0];

   [myRect setWidth:10.0 height:20.0];

   [myObject makeGroup: obj1, obj2, obj3, obj4, nil];

   float area = [myRect area];

   [myRect setColor:[otherRect color]];

   Rect * myRect = [[Rect alloc] init];

@interface Company : NSObject
{
     NSString *name;
}

@property (retain) NSString *name;

@synthesize name;

@interface ClassName : SuperClass
{
    instance variable declarations
}

method declarations
@end

@interface Rect : NSObject
{
	float     width;
	float     height;
	BOOL      isFilled;
	NSColor * color;
}
@end

@interface Rect : NSObject
{
	float     x, y;
	float     width;
	float     height;
	BOOL      isFilled;
	NSColor * color;
}
+ newRect;
- (void) display;
- (float) width;
- (float) height;
- (float) area;
- (void) setWidth: (float) theWidth;
- (void) setHeight: (float) theHeight;
- (void) setX: (float) theX y: (float) theY;
@end

- makeGroup: (id) object, ...;

@class Shape, Rect, Oval;

#import "ClassName.h"

@implementation ClassName

    method implementations

@end

#import "Rect.h"

@implementation Rect

+ newRect
{
	Rect * rect = [[Rect alloc] init];

	[rect setWidth:  1.0f];
	[rect setHeight: 1.0f];
	[rect setX: 0.0f y: 0.0f];

	return rect;
}

- (float) width
{
   return width;
}

- (float) height
{
   return height;
}

- (float) area
{
   return [self width] * [self height];
}

- (void) setWidth: (float) theWidth
{
   width = theWidth;
}

- (void) setHeight: (float) theHeight
{
   height = theHeight;
}

- (void) setX: (float) theX y: (float) theY
{
   x = theX;
   y = theY;
}

@end

@interface Worker : NSObject
{
	char * name;
@private
	int    age;
	char * evaluation;
@protected
	int    job;
	float  wage;
@public
	id     boss
}

- (void)forwardInvocation:(NSInvocation *)anInvocation
{
    if ( [someOtherObject respondsToSelector: [anInvocation selector]] )
        [anInvocation invokeWithTarget: someOtherObject];
    else
       ..........
}

   SEL setWidth = @selector(setWidth:);
   SEL setPos   = @selector(setPosition:y:);

   SEL        setWidth   = NSSelectorFromString ( @"setWidth:" );
   NSString * methodName = NSStringFromSelector  ( setPos );

    if ( [anObject respondsToSelector: @selector(setWidth:)] )
         [anObject setWidth: 200.0];

    [myObject performSelector:sel withObject: nil];

    Class    * cls     = [anObject class];
    NSString * clsName = NSStringFromClass ( cls );

    Class * cls = NSClassFromString ( clsName );

- (float) area
{
   return [self width] * [self height];
}

typedef float (*WidthFunc)( id, SEL );
typedef void  (*SetWidthFunc)( id, SEL, float );

WidthFunc    widthFunc    = (WidthFunc)    [myRect methodForSelector: @selector (width)];
SetWidthFunc setWidthFunc = (SetWidthFunc) [myRect methodForSelector: @selector (setWidth:)];

(*setWidthFunc)( myRect, @selector (setWidth:), 27.5f );

@protocol ProtocolName
method declarations
@end

@protocol Serializable
- (id)   initWithCoder: (NSCoder *) coder;
- (void) encodeWithCoder: (NSCoder *) coder;
@end

@protocol MyProto <Protocol1, Protocol2, Serializable, Drawable>

@interface MyClass : SuperClass <Protocol1, Protocol2, Serializable, Drawable>

if ( [myObject conformsToProtocol: @protocol (Serializable)] )
     [myObject encodeWithCoder: myCoder];

id <Serializable,Drawable>  myObject;

Shape <Serializable>  *myObject;

Protocol * myProto = @protocol ( Serializable );

@protocol MyProto, Serializable, Drawable;

 Cup * cup = [[Cup alloc] init];

 @try
 {
     [cup fill];
 }
 @catch ( NSException * exc )
 {
    NSLog ( @"Exception caught:%@", exc );
 }
 @catch ( id exc )
 {
    NSLog ( @"Unknown exception caught" );
 }
 @finally
 {
    [cup release];
 }

 NSException * exc = [NSException exceptionWithName: @"my-exception" reason: @"unknown-error"
                                  userInfo: nil];
 @throw exc;

- (void) criticalMethod
{
    @synchronized ( self )
    {
         // perform modifications to shared objects
         . . .
    }
}

id anObject = [[Rectangle alloc] init];

id anObject = [Rectangle alloc];

[anObject init];

- (id) initWithName: (const char *) theName   // designated initializer
{
    self = [super init];                        // call inherited method
    if (self)
    {
        name = strdup ( theName );
    }
    return self;
}

- (id) init
{
    return [self initWithName: ""];
}

+ (id) stringWithCString:(const char *)cString encoding:(NSStringEncoding)enc
+ (id) stringWithFormat:(NSString *)format, ...

- (void) dealloc
{
    . . .
    [super dealloc];
}

@interface Company : NSObject
{
    NSArray *workers;
}
-(NSArray*)workers;
@end

Company *company = [[Company alloc] init];
// ...
NSArray *workers = [company workers];
// ...
[company release];

Company *company = [Company company];
[company release];

+(Company*)company
{
     id ret = [[Company alloc] init];
     return [ret autorelease];
}

-(NSArray*)workers
{
     NSArray *copy = [[NSArray alloc] initWithArray:workers];
     return [copy autorelease];
}

-(void)dealloc
{
    [workers release];
    [super dealloc];
}

int main (int argc, const char * argv[])
{
    NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];

    Company *company = [Company company];
    NSArray *workers = [company workers];

    [pool drain];
    return 0;
}

@interface Company : NSObject <NSCopying>
{
     NSString *name;
}
@property(retain) NSString *name;
-(id)copyWithZone:(NSZone *)zone;
@end

@implementation Company
@synthesize name;
-(id)copyWithZone:(NSZone *)zone
{
     id copy = [[[self class] allocWithZone:zone] init];
     [copy setName:[self name]];
     return copy;
}
@end

id copy = [super copyWithZone:zone];

-(id)copyWithZone:(NSZone *)zone
{
     return [self retain];
}

#import "ClassName.h"
@interface ClassName ( CategoryName )
  methods declarations
@end

#import "CategoryName.h"
@implementation ClassName ( CategoryName )
  methods bodies
@end

@interface ClassName
{
  BOOL flag;
}
@property (assign, readonly) BOOL flag;
@end

#import "ClassName"
@implementation ClassName () // Пустая категория
@property (assign, readwrite) BOOL flag;
@end

@implementation ClassName
@synthesize flag;

-(void) someAction
{
  self.flag = YES;
}
@end

@protocol Printable // сущности, которые можно распечатать
-(void) print;
@end

@interface NSString(Printable) <Printable> // добавляем системному классу NSString возможность быть распечатанным
@end

@implementation NSString(Printable) // реализуем новую функциональность
-(void) print
{
  NSLog(@"Меня распечатали %@!", self);
}
@end

Method   class_getInstanceMethod( Class aClass, SEL aSelector );
Method   class_getClassMethod   ( Class aClass, SEL aSelector );
struct objc_method_list * class_nextMethodList(Class theClass, void ** iterator);
void     class_addMethods       ( Class aClass, struct objc_method_list * methodList );
void     class_removeMethods    ( Class aClass, struct objc_method_list * methodList );
unsigned method_getNumberOfArguments ( Method method );
unsigned method_getSizeOfArguments   ( Method method );
unsigned method_getArgumentInfo      ( Method method, int argIndex, const
                                       char ** type, int *  offset );
Ivar     class_getInstanceVariable   ( Class aClass, const char * aVariableName );

    void                    * iterator = 0;
    struct objc_method_list * methodList;

    //
    // Each call to class_nextMethodList returns one methodList
    //

    methodList = class_nextMethodList( classObject, &iterator  )

    while ( methodList != nil )
    {
        // …do something with the method list here…

        methodList = class_nextMethodList ( classObject, &iterator  );
    }

char * buf1 = @encode ( int ** );
char * buf2 = @encode ( struct key );
char * buf3 = @encode ( Rectangle );

   [receiver message];

   [myRect setOrigin:30.0 :50.0];

   [myRect setWidth:10.0 height:20.0];

   [myObject makeGroup: obj1, obj2, obj3, obj4, nil];

   float area = [myRect area];

   [myRect setColor:[otherRect color]];

   Rect * myRect = [[Rect alloc] init];

@interface Company : NSObject
{
     NSString *name;
}

@property (retain) NSString *name;

@synthesize name;

@interface ClassName : SuperClass
{
    instance variable declarations
}

method declarations
@end

@interface Rect : NSObject
{
	float     width;
	float     height;
	BOOL      isFilled;
	NSColor * color;
}
@end

@interface Rect : NSObject
{
	float     x, y;
	float     width;
	float     height;
	BOOL      isFilled;
	NSColor * color;
}
+ newRect;
- (void) display;
- (float) width;
- (float) height;
- (float) area;
- (void) setWidth: (float) theWidth;
- (void) setHeight: (float) theHeight;
- (void) setX: (float) theX y: (float) theY;
@end

- makeGroup: (id) object, ...;

@class Shape, Rect, Oval;

#import "ClassName.h"

@implementation ClassName

    method implementations

@end

#import "Rect.h"

@implementation Rect

+ newRect
{
	Rect * rect = [[Rect alloc] init];

	[rect setWidth:  1.0f];
	[rect setHeight: 1.0f];
	[rect setX: 0.0f y: 0.0f];

	return rect;
}

- (float) width
{
   return width;
}

- (float) height
{
   return height;
}

- (float) area
{
   return [self width] * [self height];
}

- (void) setWidth: (float) theWidth
{
   width = theWidth;
}

- (void) setHeight: (float) theHeight
{
   height = theHeight;
}

- (void) setX: (float) theX y: (float) theY
{
   x = theX;
   y = theY;
}

@end

@interface Worker : NSObject
{
	char * name;
@private
	int    age;
	char * evaluation;
@protected
	int    job;
	float  wage;
@public
	id     boss
}

- (void)forwardInvocation:(NSInvocation *)anInvocation
{
    if ( [someOtherObject respondsToSelector: [anInvocation selector]] )
        [anInvocation invokeWithTarget: someOtherObject];
    else
       ..........
}

   SEL setWidth = @selector(setWidth:);
   SEL setPos   = @selector(setPosition:y:);

   SEL        setWidth   = NSSelectorFromString ( @"setWidth:" );
   NSString * methodName = NSStringFromSelector  ( setPos );

    if ( [anObject respondsToSelector: @selector(setWidth:)] )
         [anObject setWidth: 200.0];

    [myObject performSelector:sel withObject: nil];

    Class    * cls     = [anObject class];
    NSString * clsName = NSStringFromClass ( cls );

    Class * cls = NSClassFromString ( clsName );

- (float) area
{
   return [self width] * [self height];
}

typedef float (*WidthFunc)( id, SEL );
typedef void  (*SetWidthFunc)( id, SEL, float );

WidthFunc    widthFunc    = (WidthFunc)    [myRect methodForSelector: @selector (width)];
SetWidthFunc setWidthFunc = (SetWidthFunc) [myRect methodForSelector: @selector (setWidth:)];

(*setWidthFunc)( myRect, @selector (setWidth:), 27.5f );

@protocol ProtocolName
method declarations
@end

@protocol Serializable
- (id)   initWithCoder: (NSCoder *) coder;
- (void) encodeWithCoder: (NSCoder *) coder;
@end

@protocol MyProto <Protocol1, Protocol2, Serializable, Drawable>

@interface MyClass : SuperClass <Protocol1, Protocol2, Serializable, Drawable>

if ( [myObject conformsToProtocol: @protocol (Serializable)] )
     [myObject encodeWithCoder: myCoder];

id <Serializable,Drawable>  myObject;

Shape <Serializable>  *myObject;

Protocol * myProto = @protocol ( Serializable );

@protocol MyProto, Serializable, Drawable;

 Cup * cup = [[Cup alloc] init];

 @try
 {
     [cup fill];
 }
 @catch ( NSException * exc )
 {
    NSLog ( @"Exception caught:%@", exc );
 }
 @catch ( id exc )
 {
    NSLog ( @"Unknown exception caught" );
 }
 @finally
 {
    [cup release];
 }

 NSException * exc = [NSException exceptionWithName: @"my-exception" reason: @"unknown-error"
                                  userInfo: nil];
 @throw exc;

- (void) criticalMethod
{
    @synchronized ( self )
    {
         // perform modifications to shared objects
         . . .
    }
}

id anObject = [[Rectangle alloc] init];

id anObject = [Rectangle alloc];

[anObject init];

- (id) initWithName: (const char *) theName   // designated initializer
{
    self = [super init];                        // call inherited method
    if (self)
    {
        name = strdup ( theName );
    }
    return self;
}

- (id) init
{
    return [self initWithName: ""];
}

+ (id) stringWithCString:(const char *)cString encoding:(NSStringEncoding)enc
+ (id) stringWithFormat:(NSString *)format, ...

- (void) dealloc
{
    . . .
    [super dealloc];
}

@interface Company : NSObject
{
    NSArray *workers;
}
-(NSArray*)workers;
@end

Company *company = [[Company alloc] init];
// ...
NSArray *workers = [company workers];
// ...
[company release];

Company *company = [Company company];
[company release];

+(Company*)company
{
     id ret = [[Company alloc] init];
     return [ret autorelease];
}

-(NSArray*)workers
{
     NSArray *copy = [[NSArray alloc] initWithArray:workers];
     return [copy autorelease];
}

-(void)dealloc
{
    [workers release];
    [super dealloc];
}

int main (int argc, const char * argv[])
{
    NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];

    Company *company = [Company company];
    NSArray *workers = [company workers];

    [pool drain];
    return 0;
}

@interface Company : NSObject <NSCopying>
{
     NSString *name;
}
@property(retain) NSString *name;
-(id)copyWithZone:(NSZone *)zone;
@end

@implementation Company
@synthesize name;
-(id)copyWithZone:(NSZone *)zone
{
     id copy = [[[self class] allocWithZone:zone] init];
     [copy setName:[self name]];
     return copy;
}
@end

id copy = [super copyWithZone:zone];

-(id)copyWithZone:(NSZone *)zone
{
     return [self retain];
}

#import "ClassName.h"
@interface ClassName ( CategoryName )
  methods declarations
@end

#import "CategoryName.h"
@implementation ClassName ( CategoryName )
  methods bodies
@end

@interface ClassName
{
  BOOL flag;
}
@property (assign, readonly) BOOL flag;
@end

#import "ClassName"
@implementation ClassName () // Пустая категория
@property (assign, readwrite) BOOL flag;
@end

@implementation ClassName
@synthesize flag;

-(void) someAction
{
  self.flag = YES;
}
@end

@protocol Printable // сущности, которые можно распечатать
-(void) print;
@end

@interface NSString(Printable) <Printable> // добавляем системному классу NSString возможность быть распечатанным
@end

@implementation NSString(Printable) // реализуем новую функциональность
-(void) print
{
  NSLog(@"Меня распечатали %@!", self);
}
@end

Method   class_getInstanceMethod( Class aClass, SEL aSelector );
Method   class_getClassMethod   ( Class aClass, SEL aSelector );
struct objc_method_list * class_nextMethodList(Class theClass, void ** iterator);
void     class_addMethods       ( Class aClass, struct objc_method_list * methodList );
void     class_removeMethods    ( Class aClass, struct objc_method_list * methodList );
unsigned method_getNumberOfArguments ( Method method );
unsigned method_getSizeOfArguments   ( Method method );
unsigned method_getArgumentInfo      ( Method method, int argIndex, const
                                       char ** type, int *  offset );
Ivar     class_getInstanceVariable   ( Class aClass, const char * aVariableName );

    void                    * iterator = 0;
    struct objc_method_list * methodList;

    //
    // Each call to class_nextMethodList returns one methodList
    //

    methodList = class_nextMethodList( classObject, &iterator  )

    while ( methodList != nil )
    {
        // …do something with the method list here…

        methodList = class_nextMethodList ( classObject, &iterator  );
    }

char * buf1 = @encode ( int ** );
char * buf2 = @encode ( struct key );
char * buf3 = @encode ( Rectangle );

Objective-C
Класс языка	объектно-ориентированный, мультипарадигмальный: рефлексивно-ориентированный
Появился в	1983
Автор	Брэд Кокс
Расширение файлов	`.h`, `.m`, `.mm` или `.C`
Выпуск	2.0^[1]
Система типов	слабая, статическая / динамическая
Основные реализации	Cocoa, Cocoa Touch, gcc, LLVM + Clang
Испытал влияние	Smalltalk, C
Повлиял на	Java, Objective-J, Swift
Сайт	developer.apple.com/libr…
Медиафайлы на Викискладе

Objective-C
Класс языка	объектно-ориентированный, мультипарадигмальный: рефлексивно-ориентированный
Появился в	1983
Автор	Брэд Кокс
Расширение файлов	`.h`, `.m`, `.mm` или `.C`
Выпуск	2.0^[1]
Система типов	слабая, статическая / динамическая
Основные реализации	Cocoa, Cocoa Touch, gcc, LLVM + Clang
Испытал влияние	Smalltalk, C
Повлиял на	Java, Objective-J, Swift
Сайт	developer.apple.com/libr…
Медиафайлы на Викискладе

Objective-C

Базовые принципы

Базовые принципы на практике

Autorelease-пул

Копирование объектов

Wikiwand in your browser!

Objective-C

Базовые принципы

Базовые принципы на практике

Autorelease-пул

Копирование объектов

Wikiwand in your browser!

История

Синтаксис языка

Создание новых классов

Как работает механизм сообщений

Протоколы

Обработка исключений

Синхронизация

Создание и уничтожение объектов

Управление памятью

Категории

Class objects и Objective-C runtime

Разное

См. также

Примечания

Литература

Ссылки