GCD(2)

#import "ViewController.h"

@interface ViewController ()
@property (weak, nonatomic) IBOutlet UIActivityIndicatorView *action;

@end

@implementation ViewController

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


//模拟从服务器上获取数据（返回字符串)
-(NSString *)loadingSomeThingFromServer
{
    [NSThread sleepForTimeInterval:2];
    
    return @"Hello wangdelong";
}


//    将传入参数全部转换成大写字母
-(NSString *)changname:(NSString *)result
{
    [NSThread setThreadPriority:2];
    
    return  [result uppercaseString];
}


//模拟从服务器上第一次处理数据（将从服务器上返回的字符串长度转换成字符串：（Number of chars: )
-(NSString *)dealTheResult:(NSString *)result
{
    [NSThread sleepForTimeInterval:3];
    
    return [NSString stringWithFormat:@"long of zhe thinge is :%d",result.length];
}


//模拟第二次处理服务器上的数据，将返回的字符串里的小的w转换成大写的W
-(NSString *)dealTheNewThings:(NSString *)result
{
    [NSThread sleepForTimeInterval:3];
    
    return [result stringByReplacingOccurrencesOfString:@"W" withString:@"w"];
}



- (IBAction)doSomething:(UIButton *)sender {
    
    
//    声明一个表示时间的对象，[NSDate date]获取的是当前时间
    NSDate *startTime = [NSDate date];
    
    [self.action startAnimating];


//  创建一个队列，使其实现并发－－－－－原以为能实现风火轮的准时停止，但是
    dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
    
//    异步发布
    dispatch_async(queue, ^{
        
//        //从服务器上取数据
            __block NSString *result = nil;
        
        dispatch_async(queue, ^{
            
//      处理事件
    
            result = [self loadingSomeThingFromServer];
            
            NSLog(@"********输入的是:%@",result);
            
            
            });
        
        
            result = [self changname:result];
        //    第一次处理数据
            NSString *second = [self dealTheResult:result];
        //    第二次处理数据
            NSString *third = [self dealTheNewThings:result];
            
            NSLog(@"********大写的是:%@",result);
            NSLog(@"********:%@",second);
            NSLog(@"********修改后的是:%@",third);
            
            NSDate *endTime = [NSDate date];
            
            NSLog(@"共经过 %f m时间",[endTime  timeIntervalSinceDate:startTime ]);
            
            dispatch_sync(dispatch_get_main_queue(), ^{
                [self.action stopAnimating];
            });
        
    });
}

//新添加的方法，显示最后的结果
-(void)showTheLastResult:(NSString *)first Second:(NSString *)second
{
    NSLog(@"[First:]%@,[Second:]%@",first,second);
    
}


- (IBAction)doNewThing:(UIButton *)sender {
    
//    声明一个表示时间的对象，[NSDate date]获取的是当前时间
    NSDate *startTime = [NSDate date];
    [self.action startAnimating];
    
    dispatch_queue_t queue =dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);

//   异步分发队列
    dispatch_async(queue, ^{
        
        NSString *result =[self loadingSomeThingFromServer];
        
        NSString *changName = [self changname:result];
        
        NSLog(@"********输入的是:%@",result);
        
        NSLog(@"********大写的是:%@",changName);
        
//      GCD提供了dispatch group，可以将一组任务集合在一起，等待这组任务完成后再继续，
        dispatch_group_t group =dispatch_group_create();
       
        
//      __block这里是block的用法，为了能让block能传参数
        
        __block  NSString * first ;
        
        __block NSString * second;
        
        dispatch_group_async(group, dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{

            
            first = [self dealTheResult:changName];
            NSLog(@"********:%@",first);
           
        });
        
        dispatch_group_async(group, dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
            
            
            second = [self dealTheNewThings:changName];
            
            NSLog(@"********修改后的是:%@",second);
        });
        
        dispatch_group_notify(group, dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
            
            [self showTheLastResult:first Second:second];
            
            
            dispatch_sync(dispatch_get_main_queue(), ^{
                [self.action stopAnimating];
            });
            
            
            NSLog(@"共经过 %f m时间",[[NSDate date] timeIntervalSinceDate:startTime]);
            
        });
        
        
    });
    

    
    
}

@end