iOS开发之OC与swift开发混编教程，代理的相互调用,block的实现。OC调用Swift中的代理， OC调用Swift中的Block 闭包

本文章将从两个方向分别介绍 OC 与 swift 混编

1. 第一个方向从 swift工程中引入 oc类

　 1. 1 如何在swift的类中使用oc类
1.2 如何在swift中实现oc的代理方法
1.3 如何在swift中实现oc的Block回调

2 二个方向从OC工程中引入swift类

2.1 如何在OC类中使用swift类
2.2 如何在OC中实现swift的代理方法
2.3 如何在OC中实现swift中类似Block回调

下面是具体的实现过程：

1.1 如何在swift的类中使用oc类？

1. swift工程中引入OC类。具体实现过程。

1.1 新建一个swift工程类。取名 swiftOrOC

1.2 实现的功能为：从swift. viewController.swift 中 push到 OC语言 secondViewController 控制器

1.2.1 新建SecondViewController 类。

1.2.2 建立桥接文件。（很重要）

一定要记得点击这个按钮。

1.2.3 接下来工程目录如下：

1.2.4 接下来就可以实现具体的跳转功能了。

ViewController.swift中具体实现

import UIKit

class ViewController: UIViewController {

    @IBOutlet weak var hintLabel: UILabel!  //稍后用来显示回调

    // push 到 oc controller

    @IBAction func pushAction(_ sender: AnyObject) {

        let secondVC = SecondViewController.init()

        self.navigationController?.pushViewController(secondVC, animated: true)

    }

    override func viewDidLoad() {

        super.viewDidLoad()

        // Do any additional setup after loading the view, typically from a nib.

    }

    override func didReceiveMemoryWarning() {

        super.didReceiveMemoryWarning()

        // Dispose of any resources that can be recreated.

    }

}

1.2 如何在swift中实现oc的代理方法

1.2.1 首先在 SecondViewController.h 中声明一个协议。具体代码

#import <UIKit/UIKit.h>

@protocol SecondDelegate <NSObject>

-(void)refreshHintLabel:(NSString *)hintString;

@end

@interface SecondViewController : UIViewController

@property (nonatomic,weak)id<SecondDelegate> secondDelegate;

@end

1.2.3 接下来就非常简单了，让ViewController.swift只需要成为SecondViewController的代理，然后遵循她的协议，就可以了。具体代码如下。

1.2.3.1 遵循协议

1.2.3.2 成为代理，并实现协议方法，更改controller.swift中hintLabel的text。

// push 到 oc controller
@IBAction func pushAction(_ sender: AnyObject) {
let secondVC = SecondViewController.init()
secondVC.secondDelegate = self;
self.navigationController?.pushViewController(secondVC, animated: true)
}
// SecondViewControll的代理方法
func refreshHintLabel(_ hintString: String!) {
hintLabel.text = "secondView textView.text = " + hintString;
}

1.3 如何在swift中实现oc的Block回调

1.3.1 具体过程与1.2小节一样。直接上代码。

1.3.2 声明block;

typedef void(^RefreshHintLabelBlock)(NSString *hintString);
@interface SecondViewController : UIViewController
@property (nonatomic, copy) RefreshHintLabelBlock hintBlock;
@end

1.3.3 block的回调。 SecondViewController.m中

#pragma mark 返回上一页回调 ,将用户输入的用户名传回给 ViewController.swift
-(BOOL)navigationShouldPopOnBackButton{
if (_hintBlock) {
_hintBlock(textField.text);
}
return YES;
}

1.3.4 在swift类中调用 oc的block.

// push 到 oc controller
@IBAction func pushAction(_ sender: AnyObject) {
let secondVC = SecondViewController.init()
secondVC.secondDelegate = self;
secondVC.hintBlock = {(t:String?)in
self.hintLabel.text = "secondView textView.text = " + t!
}
self.navigationController?.pushViewController(secondVC, animated: true)
}

工程已上传到git上，git地址： https://github.com/zhonggaorong/SwiftOrOc/tree/master

2. OC工程中引入swift类。具体实现过程。

耽误了不少时间，今天才开始写oc工程中引入swift类。

demo地址:

https://github.com/jukai9316/OCtoSwift

2.1 如何在OC类中使用swift类

2.1.1 新建一个基于OC语言的工程 ,取名 OcOrSwiftTwo

2.1. 2 实现的功能为：从oc类 viewcontroller中， push 至 swift语言 SecondViewController ,然后SecondViewController可以通过代理或者swift闭包把值传回viewcontroller.

2.1.3 当前文件目录看下图: （第四个箭头：桥接文件）

2.2 如何在OC中实现swift的代理与闭包Block方法

2.2.1 如何在oc中引入swift类。#import "工程名-swift.h"

#import "OcOrSwiftTwo-swift.h"

2.2.2 在secondViewController.swift 中实现代理与闭包，代码如下:

注意: @objc(代理名) 才能在外部可见这个代理

import UIKit
import Foundation
// 必须加上@objc 代理才能在oc类中可见。
@objc(EditTextFieldDelegate)
protocol EditTextFieldDelegate:NSObjectProtocol {
func editTextField(_ str: String) -> Void
}
@objc(SecondViewController)
class SecondViewController: UIViewController {
var editorDelegate:EditTextFieldDelegate?
var textField:UITextField?
var addButton:UIButton?
var pushButton:UIButton?
typealias editorBlock = (_ t:String) -> Void
var myEidtorBlock:editorBlock?
override func viewDidLoad() {
super.viewDidLoad()
self.view.backgroundColor = UIColor.white
textField = UITextField.init(frame: CGRect.init(x: 50, y: 60, width: 200, height: 50))
textField?.placeholder = "输入返回首页的内容"
self.view.addSubview(textField!)
addButton = UIButton.init(type: .custom)
addButton?.setTitleColor(UIColor.black, for: .normal)
addButton?.setTitle("pop", for: .normal)
addButton?.frame = CGRect.init(x: 50, y: 150, width: 200, height: 50)
addButton?.layer.borderColor = UIColor.black.cgColor
addButton?.layer.borderWidth = 1.0
addButton?.addTarget(self, action: #selector(popAction), for: .touchUpInside)
self.view.addSubview(addButton!)
pushButton = UIButton.init(type: .custom)
pushButton?.setTitleColor(UIColor.black, for: .normal)
pushButton?.setTitle("push", for: .normal)
pushButton?.frame = CGRect.init(x: 50, y: 250, width: 200, height: 50)
pushButton?.layer.borderColor = UIColor.black.cgColor
pushButton?.layer.borderWidth = 1.0
pushButton?.addTarget(self, action: #selector(pushAction), for: .touchUpInside)
self.view.addSubview(pushButton!)
}
func popAction() -> Void {
if editorDelegate != nil {
editorDelegate?.editTextField((textField?.text)!)
}
if ((self.myEidtorBlock) != nil){
self.myEidtorBlock!((textField?.text!)!)
}
self.navigationController?.popViewController(animated: true)
}
func pushAction() -> Void {
let three = ThreeViewController.init()
self.navigationController?.pushViewController(three, animated: true)
}

2.2.3 在oc类中viewcontroller.m 文件中实现SecondviewController.swift的相关代理与闭包(block). 代码如下:

#import "ViewController.h"
#import "OcOrSwiftTwo-swift.h"
@interface ViewController ()<EditTextFieldDelegate>
@property (nonatomic, strong) UITextField *showTextField;
@property (nonatomic, strong) UIButton *pushButton;
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
_showTextField = [[UITextField alloc]initWithFrame:CGRectMake(50, 100 , 200, 50)];
_showTextField.placeholder = @"swift传回的文本内容";
_showTextField.adjustsFontSizeToFitWidth = YES;
_showTextField.enabled = NO;
[self.view addSubview:_showTextField];
_pushButton = [UIButton buttonWithType:UIButtonTypeCustom];
[_pushButton.layer setBorderColor:[UIColor blackColor].CGColor];
[_pushButton.layer setBorderWidth:1.0];
[_pushButton setFrame:CGRectMake(50, 200, 200, 50)];
[_pushButton setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
[_pushButton setTitle:@"push" forState:UIControlStateNormal];
[_pushButton addTarget:self action:@selector(pushAction) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:_pushButton];
}
-(void)pushAction{
SecondViewController *second = [[SecondViewController alloc]init];
// second.editorDelegate = self;
/*
swift中的闭包回滴
*/
second.myEidtorBlock = ^(NSString *str) {
_showTextField.text = [NSString stringWithFormat:@"second传回信息: %@",str];
};
[self.navigationController pushViewController:second animated:YES];
}
#pragma mark swift中的代理
-(void)editTextField:(NSString *)str{
_showTextField.text = [NSString stringWithFormat:@"second传回信息: %@",str];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}