Swift and Objective-C Mixed Programming

Swift and Objective-C Mixed Programming

1. First open Xcode6 and create a project. Here I use the default Objective-C programming language. The project name is "SwiftAndObjective ".

2. To use the Swift demo in OC, you need to create the following classes.

A) create an Objective-C class that inherits from NSObject and its name is OCTypeClass. Therefore, two corresponding classes are automatically generated. m and. h file, which is very familiar with Objective-C.

B) try your best to create a Swift class named SwiftFile1. When you click Create, a prompt will pop up asking if you want to create a hander. h file. You must select here. Because if you want to use the Objective-C class in Swift, this is a necessary file and you will discuss it later. A SwiftFile1.swift file and a header file are created.

C) to describe the relationship between the public, private, and default access controllers, you need to create another Swift file named SwiftFile2, which generates a SwiftFile2.swift file.

The file has been created.

3. classes need to be defined (because swift can not inherit any classes, but if it needs to be used by Objective-C, the alloc, new, and other methods we use are inherited from NSObject, so I have inherited NSObject from these classes in Swift ).

Create the following class in the SwiftFile1.swift File

import Foundation@objc public class PublicObjcTypeSwiftClass1: NSObject {    var property1: Int = 0}@objc class ObjcTypeSwiftClass1: NSObject {    var property1: Int = 0}@objc private class ObjcPrivateTypeSwiftClass1: NSObject {    var property1: Int = 0}public class PublicSwiftClass1 : NSObject {    var property1: Int = 0}class SwiftClass1: NSObject {    var property1: Int = 0}private class PrivateSwiftClass1: NSObject {    var property1: Int = 0}

Create the following class in SwiftFile2.swift

import Foundation@objc public class PublicObjcTypeSwiftClass2: NSObject {    var property1: Int = 0    //var ocClass: OCTypeClass = OCTypeClass()        //func test() {    //    ocClass.property1 = 0    //}}@objc class ObjcTypeSwiftClass2: NSObject {    var property1: Int = 0}@objc private class ObjcPrivateTypeSwiftClass2: NSObject {    var property1: Int = 0}public class PublicSwiftClass2: NSObject {    var property1: Int = 0}class SwiftClass2: NSObject {    var property1: Int = 0}private class PrivateSwiftClass2: NSObject {    var property1: Int = 0}


4. Because the corresponding class is automatically generated after the OC file is defined, you do not need to define it again.
#import "OCTypeClass.h"#import "SwiftAndObjective-Swift.h"@implementation OCTypeClass- (void)test{    PublicObjcTypeSwiftClass1 *type = [[PublicObjcTypeSwiftClass1 alloc] init];    type.property1 = 0;            ObjcTypeSwiftClass1 *type2 = [[ObjcTypeSwiftClass1 alloc] init];    type2.property1 = 0;}@end


5. Open the OCTypeClass. m file and we need to reference the class in the Swift file. You can use "project name + '-' + Swfit. h "is introduced to the public class and marked as @ objc (marked as @ objc class, even if the public mark is not displayed, it will be used by the Objective-C class ). The specific code below (note that when # import "" is used, Xcode of the current version does not automatically recognize the required Swift header name. You need to manually write the code yourself. Note: do not write the wrong Project name. If you confirm that the Project is correct, but keep reporting errors, You can refresh the Project, or restart and re-build: Project-Clean, Project-Build, big deal restart Xcode ).

6. After that, you can view the Objective-C Class automatically generated by xcode in the form of source code (command + left mouse button.
// Generated by Swift version 1.1 (swift-600.0.54.20)#pragma clang diagnostic push#if defined(__has_include) && __has_include(
  
   )# include 
   
    #endif#pragma clang diagnostic ignored "-Wauto-import"#include 
    
     #include 
     
      #include 
      
       #include 
       
        #if defined(__has_include) && __has_include(
        
         )# include 
         
          #elif !defined(__cplusplus) || __cplusplus < 201103Ltypedef uint_least16_t char16_t;typedef uint_least32_t char32_t;#endiftypedef struct _NSZone NSZone;#if !defined(SWIFT_PASTE)# define SWIFT_PASTE_HELPER(x, y) x##y# define SWIFT_PASTE(x, y) SWIFT_PASTE_HELPER(x, y)#endif#if !defined(SWIFT_METATYPE)# define SWIFT_METATYPE(X) Class#endif#if defined(__has_attribute) && __has_attribute(objc_runtime_name)# define SWIFT_RUNTIME_NAME(X) __attribute__((objc_runtime_name(X)))#else# define SWIFT_RUNTIME_NAME(X)#endif#if !defined(SWIFT_CLASS_EXTRA)# define SWIFT_CLASS_EXTRA#endif#if !defined(SWIFT_PROTOCOL_EXTRA)# define SWIFT_PROTOCOL_EXTRA#endif#if !defined(SWIFT_CLASS)# if defined(__has_attribute) && __has_attribute(objc_subclassing_restricted) # define SWIFT_CLASS(SWIFT_NAME) SWIFT_RUNTIME_NAME(SWIFT_NAME) __attribute__((objc_subclassing_restricted)) SWIFT_CLASS_EXTRA# else# define SWIFT_CLASS(SWIFT_NAME) SWIFT_RUNTIME_NAME(SWIFT_NAME) SWIFT_CLASS_EXTRA# endif#endif#if !defined(SWIFT_PROTOCOL)# define SWIFT_PROTOCOL(SWIFT_NAME) SWIFT_RUNTIME_NAME(SWIFT_NAME) SWIFT_PROTOCOL_EXTRA#endif#if !defined(SWIFT_EXTENSION)# define SWIFT_EXTENSION(M) SWIFT_PASTE(M##_Swift_, __LINE__)#endif#if !defined(OBJC_DESIGNATED_INITIALIZER)# if defined(__has_attribute) && __has_attribute(objc_designated_initializer)# define OBJC_DESIGNATED_INITIALIZER __attribute__((objc_designated_initializer))# else# define OBJC_DESIGNATED_INITIALIZER# endif#endif#if defined(__has_feature) && __has_feature(modules)@import ObjectiveC;#endif#pragma clang diagnostic ignored "-Wproperty-attribute-mismatch"#pragma clang diagnostic ignored "-Wduplicate-method-arg"SWIFT_CLASS("_TtC17SwiftAndObjective19ObjcTypeSwiftClass1")@interface ObjcTypeSwiftClass1 : NSObject@property (nonatomic) NSInteger property1;- (instancetype)init OBJC_DESIGNATED_INITIALIZER;@endSWIFT_CLASS("_TtC17SwiftAndObjective19ObjcTypeSwiftClass2")@interface ObjcTypeSwiftClass2 : NSObject@property (nonatomic) NSInteger property1;- (instancetype)init OBJC_DESIGNATED_INITIALIZER;@endSWIFT_CLASS("_TtC17SwiftAndObjective25PublicObjcTypeSwiftClass1")@interface PublicObjcTypeSwiftClass1 : NSObject@property (nonatomic) NSInteger property1;- (instancetype)init OBJC_DESIGNATED_INITIALIZER;@endSWIFT_CLASS("_TtC17SwiftAndObjective25PublicObjcTypeSwiftClass2")@interface PublicObjcTypeSwiftClass2 : NSObject@property (nonatomic) NSInteger property1;- (instancetype)init OBJC_DESIGNATED_INITIALIZER;@endSWIFT_CLASS("_TtC17SwiftAndObjective17PublicSwiftClass1")@interface PublicSwiftClass1 : NSObject@property (nonatomic) NSInteger property1;- (instancetype)init OBJC_DESIGNATED_INITIALIZER;@endSWIFT_CLASS("_TtC17SwiftAndObjective17PublicSwiftClass2")@interface PublicSwiftClass2 : NSObject@property (nonatomic) NSInteger property1;- (instancetype)init OBJC_DESIGNATED_INITIALIZER;@endSWIFT_CLASS("_TtC17SwiftAndObjective11SwiftClass1")@interface SwiftClass1 : NSObject@property (nonatomic) NSInteger property1;- (instancetype)init OBJC_DESIGNATED_INITIALIZER;@endSWIFT_CLASS("_TtC17SwiftAndObjective11SwiftClass2")@interface SwiftClass2 : NSObject@property (nonatomic) NSInteger property1;- (instancetype)init OBJC_DESIGNATED_INITIALIZER;@end#pragma clang diagnostic pop
         
        
       
      
     
    
   
  


7. The following describes how to use the Objective-C Class in the Swift file.
A) Open xcode's automatically generated SwiftAndObjective-Bridging-Header.h file and import the class exposed to swift.
Here we use the class just defined for convenience, just for Demonstration:
# Import "OCTypeClass. h"
B) Then we don't need to do anything. Implement it directly in the Swfit file.
import Foundation@objc public class PublicObjcTypeSwiftClass2: NSObject {    var property1: Int = 0    var ocClass: OCTypeClass = OCTypeClass()        func test() {        ocClass.property1 = 0    }}@objc class ObjcTypeSwiftClass2: NSObject {    var property1: Int = 0}@objc private class ObjcPrivateTypeSwiftClass2: NSObject {    var property1: Int = 0}public class PublicSwiftClass2: NSObject {    var property1: Int = 0}class SwiftClass2: NSObject {    var property1: Int = 0}private class PrivateSwiftClass2: NSObject {    var property1: Int = 0}


Note:
1. If you want to expose a Swfit class to Objective-C, you need to mark @ objc.
2. For private Swift classes, they can only be used in the defined Swift file.
3. The class in a Swift file can only access the public class defined in the external Swift file.

I almost ignored the most important point: if you have any questions or errors, please correct them or contact me.

Sample Code: Code
Http://download.csdn.net/detail/liyan223/8070805