GCD多线程机制

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    //向主线程添加一个任务
    //同步添加任务
    //GCD 主线程 dispatch_get_main_queue()
    //NSOperationQueue 主线程 [NSOperationQueue mainQueue]
//    dispatch_sync(dispatch_get_main_queue(), ^{
//        NSLog(@"1");
//    });
    
    //异步添加任务
    dispatch_async(dispatch_get_main_queue(), ^{
        NSLog(@"%@",[NSThread currentThread]);
    });
    
    
    
}
//串行队列
- (IBAction)dispatchQueueSerial:(id)sender {
    //创建串行队列
    //指针
    //dispatch_queue_create(字符串指队列的标识,串行或并行)
    dispatch_queue_t queue = dispatch_queue_create("com.lanou3g.queue1",DISPATCH_QUEUE_SERIAL );
    //添加任务
    dispatch_async(queue, ^{
        for ( int i = 0; i <100; i++) {
            NSLog(@"1,%@",[NSThread currentThread]);
        }
    });
    dispatch_async(queue, ^{
        for (int i = 0; i < 100; i++) {
             NSLog(@"2,%@",[NSThread currentThread]);
        }
       
    });
    
   
    
    
}
//全局队列
- (IBAction)Dispatch_global_queue:(id)sender {
   //苹果预置了全局队列,并行队列
    //dispatch_get_global_queue(队列优先级,占位0)
    dispatch_queue_t global = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
    //添加任务
    dispatch_async(global, ^{
        NSLog(@"1,%@",[NSThread currentThread]);
    });
    dispatch_async(global, ^{
        NSLog(@"2,%@",[NSThread currentThread]);
    });
    
    
    
}
//并行队列和全局队列是一样的
- (IBAction)dispatch_queue_concurrent:(id)sender {
    dispatch_queue_t conQueue = dispatch_queue_create ("com.lanou3g.concurrent1", DISPATCH_QUEUE_CONCURRENT);
    //添加任务
    dispatch_async(conQueue, ^{
        for (int i = 0; i < 100; i++) {
            NSLog(@"1,%@",[NSThread currentThread]);

        }
    });
    dispatch_async(conQueue, ^{
        for (int i = 0; i < 100; i++) {
            NSLog(@"2,%@",[NSThread currentThread]);
            
        }
    });
}
//延时执行
- (IBAction)DISPATCH_AFTER:(id)sender {
    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(3 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
        NSLog(@"延时,%@",[NSThread currentThread]);
    });
    
    
}
//重复执行
- (IBAction)ReceiveMemoryWarning:(id)sender {
    //记得天机size_t的参数
    size_t count = 10;
    dispatch_apply(count, dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT,0), ^(size_t i) {
        NSLog(@"执行的次数:%ld",i);
    });
}
//任务添加到队列后,等待其他任务执行后再执行

- (IBAction)DISPATCH_GROUP_NOTIFY:(id)sender {
    //把线程队列添加到组中
    //dispatch_group_async()向组中添加队列
    //dispatch_group_notify()添加任务,会等待其他任务执行完毕
    //创建线程组
    dispatch_group_t group = dispatch_group_create();
    dispatch_queue_t conQueue = dispatch_queue_create("com.lanou", DISPATCH_QUEUE_CONCURRENT);
    //添加任务
    dispatch_group_async(group, conQueue, ^{
        for (int i = 0; i <100; i++) {
            NSLog(@"1,%@",[NSThread currentThread]);

        }
    });
    dispatch_group_async(group, conQueue, ^{
        for (int i = 0; i <100; i++) {
            NSLog(@"2,%@",[NSThread currentThread]);
            
        }
    });
    //监听其他任务
    dispatch_group_notify(group, conQueue, ^{
        NSLog(@"等待其他任务执行后,再执行");
    });
}
//当前barrier线程执行时,其他任务停止
- (IBAction)dispatchbarrieradync:(id)sender {
    dispatch_queue_t conQueue = dispatch_queue_create("com.lanou.conQueue", DISPATCH_QUEUE_CONCURRENT);
    //添加任务
    dispatch_async(conQueue, ^{
        for (int i = 0; i < 100; i++) {
            NSLog(@"1,%@",[NSThread currentThread]);
        }
    });
    dispatch_async(conQueue, ^{
        for (int i = 0; i < 100; i++) {
            NSLog(@"2,%@",[NSThread currentThread]);
        }
    });
    //添加barrier任务
    dispatch_barrier_async(conQueue, ^{
        for (int i = 0; i < 100; i++) {
            NSLog(@"barrier,%@",[NSThread currentThread]);
        }
    });
    dispatch_async(conQueue, ^{
        for (int i = 0; i < 100; i++) {
            NSLog(@"4,%@",[NSThread currentThread]);
        }
    });
    
    
}

//
- (IBAction)dispatchAsyncF:(id)sender {
    
    dispatch_async_f(dispatch_get_main_queue(), nil, myFunction);   
    
}
//定义函数
void myFunction(){
    for (int i = 0 ; i <100; i++) {
        NSLog(@"1,%@",[NSThread currentThread]);
    }
}

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

@end