Question

timer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(myMethod) userInfo:nil repeats:YES];

-(void)myMethod {
//my every second requirment

//my every minute requirment
}

我的计时器每秒都会抽搐并且是我的要求，但我有另一个要求，例如当我的应用程序启动时间为10:05:30时，我想触发一些代码，当它的10:06:00时再次触及它的10： 07:00然后继续。

我想这样做

date1 = dateFormatter ... date // this will give 10:05:30

date2 = dateFormatter ... date // this will give 10:05:00
date2 = addition of minute // this will give 10:06:00

and finally date1 compare date2 == descending // means it currently 10:06:00

但它看起来不是一个好的解决方案，有没有更好的解决方案？

Answer 1

此解决方案效率更高，但请考虑a tolerance of the NSTimer

@interface ViewController ()
@property (nonatomic, assign) NSInteger timerMinuteAddition;
@end

@implementation ViewController

- (void)yourScope {
    // Here you compute the initial addition to the full minute
    NSDate *currentDate = [NSDate new];
    NSCalendar *calendar = [NSCalendar currentCalendar];
    NSDateComponents *components = [calendar components:NSCalendarUnitSecond fromDate:currentDate];
    self.timerMinuteAddition = 60 - [components second];

    timer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(myMethod) userInfo:nil repeats:YES];
}

- (void)myMethod {
    // your every second requirment

    self.timerMinuteAddition--;
    if (self.timerMinuteAddition == 0) {
        // your every minute requirment

        self.timerMinuteAddition = 60;
    }
}

Answer 2

这个解决方案只是调整计时器开火日期，而不是让你的计时器每隔一秒工作一次，调整计时器开火时间，让我们保持你的计时器间隔60秒应该是

- (IBAction)startTimerCounting:(id)sender {
    NSDate * date = [NSDate date];
    NSInteger seconds = [[NSCalendar currentCalendar] component:NSCalendarUnitSecond fromDate:date];
    NSLog(@"%i",seconds);
    self.timer = [NSTimer scheduledTimerWithTimeInterval:60 target:self selector:@selector(myMethod) userInfo:nil repeats:YES];
    if(seconds > 0){
        NSDateComponents * components = [[NSDateComponents alloc] init];
        [components setSecond:60 - seconds];
        NSDate * fireDate = [[NSCalendar currentCalendar] dateByAddingComponents:components toDate:date options:NSCalendarMatchStrictly];
        [self.timer setFireDate:fireDate];
    }
}

- (void)myMethod{
    NSLog(@"timer executed");
}

这就像一个时钟，;）

提取分钟形式NSTimer每秒抽搐一次

2 个答案: