iOS--代理

描述：
两个控制器(ViewController和SecondController)和一个view(TestView);控制器带导航；TestView视图引入到ViewController中，TestView中声明一个代理协议，方法是点击在view中的一个button可以push到SecondController，让ViewController遵守协议。

结构：

屏幕快照 2016-09-07 19.45.01.png

代码:

- AppDelegate

//
//  AppDelegate.m
//  luckyCoderCai_delegateTest
//
//  Created by luckyCoderCai on 16/9/7.
//  Copyright © 2016年 luckyCoderCai. All rights reserved.
//

#import "AppDelegate.h"
#import "ViewController.h"

@interface AppDelegate ()

@end

@implementation AppDelegate


- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    // Override point for customization after application launch.
    
    self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
    self.window.backgroundColor = [UIColor orangeColor];
    
    ViewController *vc = [[ViewController alloc] init];
    
    UINavigationController *nav = [[UINavigationController alloc] initWithRootViewController:vc];
    
    self.window.rootViewController = nav;
    
    [self.window makeKeyAndVisible];
    
    return YES;
}

- (void)applicationWillResignActive:(UIApplication *)application {
    // Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
    // Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. Games should use this method to pause the game.
}

- (void)applicationDidEnterBackground:(UIApplication *)application {
    // Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later.
    // If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
}

- (void)applicationWillEnterForeground:(UIApplication *)application {
    // Called as part of the transition from the background to the inactive state; here you can undo many of the changes made on entering the background.
}

- (void)applicationDidBecomeActive:(UIApplication *)application {
    // Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
}

- (void)applicationWillTerminate:(UIApplication *)application {
    // Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
}

@end

- ViewController

//
//  ViewController.m
//  luckyCoderCai_delegateTest
//
//  Created by luckyCoderCai on 16/9/7.
//  Copyright © 2016年 luckyCoderCai. All rights reserved.
//

#import "ViewController.h"
#import "TestView.h"
#import "SecondController.h"

@interface ViewController ()//遵守代理协议

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    
    self.title = @"ViewController";
    
    self.view.backgroundColor = [UIColor cyanColor];
    
    [self createUI];
    
}

/**
 *  UI
 */
- (void)createUI
{
    TestView *testView = [[TestView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];
    //设置代理对象
    testView.delegate = self;
    [self.view addSubview:testView];
}

#pragma mark -代理
- (void)pushNextController
{
    //代理对象执行方法
    SecondController *secondVC = [[SecondController alloc] init];
    [self.navigationController pushViewController:secondVC animated:YES];
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end

- SecondController

//
//  SecondController.m
//  luckyCoderCai_delegateTest
//
//  Created by luckyCoderCai on 16/9/7.
//  Copyright © 2016年 luckyCoderCai. All rights reserved.
//

#import "SecondController.h"

@interface SecondController ()

@end

@implementation SecondController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    
    self.title = @"SecondVC";
    self.view.backgroundColor = [UIColor purpleColor];
    
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

/*
#pragma mark - Navigation

// In a storyboard-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
    // Get the new view controller using [segue destinationViewController].
    // Pass the selected object to the new view controller.
}
*/

@end

- TestView

.h:

//
//  TestView.h
//  luckyCoderCai_delegateTest
//
//  Created by luckyCoderCai on 16/9/7.
//  Copyright © 2016年 luckyCoderCai. All rights reserved.
//

#import 

/**
 *  代理协议名称
 */
@protocol LuckyCoderCaiDelegate 

//方法 可选
@optional
- (void)pushNextController;

@end

@interface TestView : UIView

//声明代理属性
@property (nonatomic, weak) iddelegate;

@end

.m:

//
//  TestView.m
//  luckyCoderCai_delegateTest
//
//  Created by luckyCoderCai on 16/9/7.
//  Copyright © 2016年 luckyCoderCai. All rights reserved.
//

#import "TestView.h"

@implementation TestView

- (instancetype)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        [self initViews];
    }
    return self;
}

- (void)initViews
{
    self.backgroundColor = [UIColor yellowColor];
    UIButton *pushBtn = [UIButton buttonWithType:UIButtonTypeCustom];
    pushBtn.backgroundColor = [UIColor blueColor];
    pushBtn.frame = CGRectMake(100, 100, 80, 30);
    [pushBtn setTitle:@"push" forState:UIControlStateNormal];
    [pushBtn setTitleColor:[UIColor redColor] forState:UIControlStateNormal];
    pushBtn.titleLabel.font = [UIFont systemFontOfSize:16];
    [pushBtn addTarget:self action:@selector(pushBtnAction) forControlEvents:UIControlEventTouchUpInside];
    [self addSubview:pushBtn];
    
}

#pragma mark -
- (void)pushBtnAction
{
    //安全判断
    if (self.delegate && [self.delegate respondsToSelector:@selector(pushNextController)]) {
        //代理执行
        [self.delegate pushNextController];
    }
}

@end