runloop 和 CFRunLoop - 定时器 - NSTimer 和 GCD定时器

1.

2、

#import "ViewController.h"

@interface ViewController ()
@property (nonatomic, strong) dispatch_source_t timer;
@end

@implementation ViewController

-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
    [self gcdTimer];
}


/**
 GCD定时器
 */
-(void)gcdTimer{
    
    
    /**
      DISPATCH_SOURCE_TYPE_TIMER 定时器
      0 描述信息
      0 更详细的描述信息
      dispatchQueue ： 队列决定定时器任务在哪个线程
     */
//    dispatch_source_t timer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0, dispatch_get_main_queue());
    dispatch_source_t timer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0, dispatch_get_global_queue(0, 0));
    
    /*
     DISPATCH_TIME_NOW :起始时间
     intervalInSeconds 间隔时间
     leewayInSeconds 精准度， 绝对精准0
     */
    dispatch_source_set_timer(timer, DISPATCH_TIME_NOW, 2 * NSEC_PER_SEC, 0 * NSEC_PER_SEC);
    
    /*
     定时器任务
     */
    dispatch_source_set_event_handler(timer, ^{
        NSLog(@"=== %@", [NSThread currentThread]);
    });
    dispatch_resume(timer);
    
    /*
     此时 定时器不会工作， 因为定时器有可能被释放掉了，异步线程和主线程都不会执行 ，需要强引用， strong，
     GCD定时器是绝对精准的，拖拽tableview或者textview都会执行，NSTimer 分界面追踪模式和默认模式 
     */
    
    self.timer = timer;
}

-(void)runloopTimer{
    NSTimer *timer = [NSTimer scheduledTimerWithTimeInterval:2 target:self selector:@selector(runTimer) userInfo:nil repeats:YES];// 在主线程
    
    // NSRunLoopCommonModes:会同时执行默认模式（NSDefaultRunLoopMode）和界面追踪模式（UITrackingRunLoopMode）
    [[NSRunLoop currentRunLoop] addTimer:timer forMode:UITrackingRunLoopMode]; // 等价于 CFRunLoopAddTimer （参数1，参数2，参数3）
}
- (void)runloopTimer22{
    NSRunLoop *runloop = [NSRunLoop currentRunLoop];
    
    /**
     默认是NSDefaultRunLoopMode
     */
    [NSTimer scheduledTimerWithTimeInterval:2 target:self selector:@selector(runTimer) userInfo:nil repeats:YES];
    [runloop run];
}


-(void)runTimer{
    NSLog(@"===%@====",[NSThread currentThread]);
}

-(void)runLoop{
    //主线程runloop
    NSRunLoop *mainRunloop = [NSRunLoop mainRunLoop];
    NSLog(@"mainRunloop =========== %p", mainRunloop);
    //    NSLog(@"mainRunloop 是个啥 === %@", mainRunloop);//打印一坨东西看不明白
    
    //当前线程runloop
    NSRunLoop * currentRunLoop = [NSRunLoop currentRunLoop];
    NSLog(@"currentRunLoop ======== %p", currentRunLoop);
    
    //core
    NSLog(@"CFRunLoopGetMain ====== %p", CFRunLoopGetMain());
    NSLog(@"CFRunLoopGetCurrent === %p", CFRunLoopGetCurrent());
    
    //转换
    NSLog(@"mainRunloop.getCFRunLoop  === %p", mainRunloop.getCFRunLoop);
    NSLog(@"currentRunLoop .getCFRunLoop  === %p", currentRunLoop.getCFRunLoop);
    /*
     2018-07-06 13:52:44.552563+0800 10 - runloop[12596:484429] mainRunloop =========== 0x6040000a2be0
     2018-07-06 13:52:44.552908+0800 10 - runloop[12596:484429] currentRunLoop ======== 0x6040000a2be0
     2018-07-06 13:52:44.553043+0800 10 - runloop[12596:484429] CFRunLoopGetMain ====== 0x6000001f3600
     2018-07-06 13:52:44.553121+0800 10 - runloop[12596:484429] CFRunLoopGetCurrent === 0x6000001f3600
     */
}



@end