block和delegate的使用

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/**

 *  功能：

 *  1. 分别通过delegate和block方式实现，点击TestTableViewCell上添加的按钮push到一个指定的控制器（TestViewController）

 *  2. 当点击cell上的按钮的时候，传一个值（当前cell的row）给ViewController控制器

 *  3. 当ViewController控制器收到Cell传来的值之后，再返回一个值给TestTabelViewCell，从而达到回调目的

 */

ViewController.m

//
//  ViewController.m
//  MyLayoutSimple
//
//  Created by shlity on 16/5/5.
//  Copyright © 2016年 shlity. All rights reserved.
//

#import "ViewController.h"
#import "TestViewController.h"
#import "TestTableViewCell.h"

@interface ViewController ()<UITableViewDataSource,UITableViewDelegate,CellPushControllerDelegate>

@property (nonatomic,retain)UITableView     *tableView;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    self.view.backgroundColor = [UIColor whiteColor];
    
    [self tableView];
    
    // Do any additional setup after loading the view, typically from a nib.
}

- (UITableView *)tableView
{
    if (!_tableView) {
        _tableView = [[UITableView alloc]initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height) style:UITableViewStylePlain];
        _tableView.delegate = self;
        _tableView.dataSource = self;
        [self.view addSubview:_tableView];
    }
    return _tableView;
}


- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section;
{
    return 40;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *identifyCell = @"cell";
    TestTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:identifyCell];
    if (!cell) {
        cell = [[TestTableViewCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:identifyCell];
        cell.delegate = self;
    }
    
    [cell startPushViewControllerWithBlock:^NSString *(NSString *strName) {
        //TestViewController *testVC = [[TestViewController alloc]init];
        //[self.navigationController pushViewController:testVC animated:YES];
        NSLog(@"strName:%@",strName);
        return [self getCurrentDate];
    }];
    
    [cell configureCellWithData:indexPath.row];
    return cell;
}

#pragma mark -- CellPushControllerDelegate
- (NSString *)pushViewController:(NSString *)str
{
    //TestViewController *testVC = [[TestViewController alloc]init];
    //[self.navigationController pushViewController:testVC animated:YES];
    
    NSLog(@"str:%@",str);
    
    return [self getCurrentDate];
}

- (NSString *)getCurrentDate
{
    NSDate *currentDate = [NSDate date];//获取当前时间，日期
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    [dateFormatter setDateFormat:@"YYYY/MM/dd hh:mm:ss SS"];
    NSString *dateString = [dateFormatter stringFromDate:currentDate];
    return dateString;
}

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

@end

//
//  TestTableViewCell.h
//  MyLayoutSimple
//
//  Created by shlity on 16/5/6.
//  Copyright © 2016年 shlity. All rights reserved.
//

#import <UIKit/UIKit.h>

/**
 *  功能：
 *  1. 分别通过delegate和block方式实现，点击TestTableViewCell上添加的按钮push到一个指定的控制器（TestViewController）
 *  2. 当点击cell上的按钮的时候，传一个值（当前cell的row）给ViewController控制器
 *  3. 当ViewController控制器收到Cell传来的值之后，再返回一个值给TestTabelViewCell，从而达到回调目的
 */

//步骤1 申明一个block
typedef NSString *(^PushViewController)(NSString *strName);

@protocol CellPushControllerDelegate <NSObject>

@optional

- (NSString *)pushViewController:(NSString *)str;

@end

@interface TestTableViewCell : UITableViewCell


@property (nonatomic,weak)id <CellPushControllerDelegate>delegate;

//步骤2 声明一个block属性
@property (nonatomic,copy)PushViewController myBlock;

- (void)configureCellWithData:(NSInteger )row;

//步骤3 将block作为参数作为方法的属性
- (void)startPushViewControllerWithBlock:(PushViewController)block;

@end

//
//  TestTableViewCell.m
//  MyLayoutSimple
//
//  Created by shlity on 16/5/6.
//  Copyright © 2016年 shlity. All rights reserved.
//

#import "TestTableViewCell.h"

@implementation TestTableViewCell
{
    UIButton *button;
}

- (instancetype)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier
{
    self = [super initWithStyle:style reuseIdentifier:reuseIdentifier];
    if (self) {
        button = [[UIButton alloc]initWithFrame:CGRectMake(0, 0, self.frame.size.width, 44)];
        [button setBackgroundColor:[UIColor orangeColor]];
        [self.contentView addSubview:button];
    }
    return self;
}

- (void)configureCellWithData:(NSInteger )row
{
    button.tag = row;
    [button addTarget:self action:@selector(clickAction:) forControlEvents:UIControlEventTouchUpInside];
}

// 步骤5 点击按钮时执行block方法
- (void)clickAction:(UIButton *)btn
{
    /**
     *  通过delegate方式来回调
     */
    /*
    if (self.delegate && [self.delegate respondsToSelector:@selector(pushViewController:)]) {
        NSString *resutl = [self.delegate pushViewController:[NSString stringWithFormat:@"%ld",btn.tag]];
        NSLog(@"result:%@",resutl);
    }
    */
    
    /**
     *  通过block方式来回调
     */
    // 步骤6 点击按钮时执行block方法传给ViewController控制器的值，以及ViewController返回给当前cell中的值
    NSString * result = self.myBlock([NSString stringWithFormat:@"%ld",btn.tag]);
    NSLog(@"result:%@",result);
}

// 步骤4 将方法中的block属性赋值给申请的block属性
-(void)startPushViewControllerWithBlock:(PushViewController)block
{
    self.myBlock = block;
}

- (void)awakeFromNib {
    // Initialization code
}

- (void)setSelected:(BOOL)selected animated:(BOOL)animated {
    [super setSelected:selected animated:animated];

    // Configure the view for the selected state
}

@end

block和delegate的使用

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原文地址：http://blog.csdn.net/mayday550/article/details/51333621