页面传值总结Block

//  AppDelegate.m
//  页面传值总结
//
//  Created by qianfeng on 15/6/13.
//  Copyright (c) 2015年 qianfeng. All rights reserved.
//

#import "AppDelegate.h"
#import "ViewController.h"
@interface AppDelegate ()

@end

@implementation AppDelegate

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {

    ViewController *ctr = [[ViewController alloc]init];
    UINavigationController*nav = [[UINavigationController alloc]initWithRootViewController:ctr];
    self.window.rootViewController = nav;

    return YES;
}

//
//  ViewController.m
//  页面传值总结
//
//  Created by qianfeng on 15/6/13.
//  Copyright (c) 2015年 qianfeng. All rights reserved.
//

#import "ViewController.h"
#import "DetailVIewController.h"

@interface ViewController ()
{
    UILabel*_label;

}
@property(nonatomic,strong)UILabel*label;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    self.view.backgroundColor = [UIColor whiteColor];

    //用于显示第二个界面传过来的数据。
    _label = [[UILabel alloc]initWithFrame:CGRectMake(120, 220, 100, 40)];
    _label.backgroundColor = [UIColor orangeColor];
    [self.view addSubview:_label];

    //创建用于跳转到第二个界面的按钮；
    UIButton*btn = [self createBtnFrame:CGRectMake(120, 300, 100, 40) title:@"跳转" target:self action:@selector(clickBtn:)];
    btn.backgroundColor = [UIColor grayColor];
    [self.view addSubview:btn];

}

-(void)clickBtn:(id)sender
{
    DetailVIewController*ctr = [[DetailVIewController alloc]init];
    __weak ViewController*weakself =self;
    ctr.clockBlock = ^(NSString*title){
        weakself.label.text = title;

    };
       [self.navigationController pushViewController:ctr animated:YES];

}

-(UIButton*)createBtnFrame:(CGRect)frame title:(NSString*)title target:(id)target action:(SEL)action
{
    UIButton*btn= [UIButton buttonWithType:UIButtonTypeSystem];
    btn.frame = frame;
    [btn setTitle:title forState:UIControlStateNormal];
    [btn addTarget:target action:action forControlEvents:UIControlEventTouchUpInside];

    return btn;

}

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

@end

//
//  DetailVIewController.h
//  页面传值总结
//
//  Created by qianfeng on 15/6/13.
//  Copyright (c) 2015年 qianfeng. All rights reserved.
//

#import <UIKit/UIKit.h>

@interface DetailVIewController : UIViewController

//声明block
@property(nonatomic,copy)void(^clockBlock)(NSString*titler);

@end

//
//  DetailVIewController.m
//  页面传值总结
//
//  Created by qianfeng on 15/6/13.
//  Copyright (c) 2015年 qianfeng. All rights reserved.
//

#import "DetailVIewController.h"

@implementation DetailVIewController

-(void)viewDidLoad
{
    [super viewDidLoad] ;
    self.view.backgroundColor = [UIColor whiteColor];

    UIButton*bt1 = [self createBtnFrame:CGRectMake(200, 140, 100, 40) title:@"block传值" target:self action:@selector(blockClick:)];
    [self.view addSubview:bt1];

}
-(void)blockClick:(UIButton*)sender
{
    NSString*title = [sender currentTitle];

    if (self.clockBlock) {
        self.clockBlock(title);
    }
}
-(UIButton*)createBtnFrame:(CGRect)frame title:(NSString*)title target:(id)target action:(SEL)action
{
    UIButton*btn= [UIButton buttonWithType:UIButtonTypeSystem];
    btn.frame = frame;
    [btn setTitle:title forState:UIControlStateNormal];
    [btn addTarget:target action:action forControlEvents:UIControlEventTouchUpInside];

    return btn;

}

@end