NSTimerfire我们先用 NSTimer 来做个简单的计时器，每隔5秒钟在控制台输出 Fire 。比较想当然的做法是这样的：12345678910111213141516@interface DetailViewController ()@property (nonatomic

double delayInSeconds = 2.0;        dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, delayInSeconds * NSEC_PER_SEC);        dispatch_after(popTime, dispatch_get_main_queue(), ^(void){ 

//–––––––––––––––––––––单例.h––––––––––––––––––––––––#import <Foundation/Foundation.h>@interface CaptchaTimerManager :NSObject@property (nonatomic,assign)__blockint timeout;+ (id)sharedT...