NSTimer天倒计时和发送到标签

Question

我有一个按钮触发NSTimer倒计时3天。如何在tableviewCell中显示剩余2天或0天的标签。并且我还想在剩下0天时用红色对单元格着色。并在单元格中有一个按钮来重置计时器另外3天。 Objective-C的。提前致谢！

Answer 1

在用户默认值中存储定时器过期日期。这可以通过IBAction方法来设置新的过期日期。再次运行此操作会重置该值。

NSInteger expiredInDays = 3; 

// Calculate the Date. 
// Get the Date 
NSDate * now = [NSDate date]; 
NSTimeInterval tiNow = [now timeIntervalSinceReferenceDate]; 
tiNow = tiNow + 60*60*24*expiredInDays; 
NSDate * expires = [NSDate dateWithTimeIntervalSinceReferenceDate:tiNow]; 
[[NSUserDefaults standardUserDefaults] setObject:expires forKey:@"Expired Date"]; 

要求即将到期的日期，您需要在代码中使用它。

NSDate *expiredDate = [[NSUserDefaults standardUserDefaults] objectForKey:@"Expired Date"]; 
NSLog(@"Expires in: %@",expiredDate); 

Answer 2

的答案是这样的：

- (IBAction)In3DaysButton:(id)sender 
    { 
    NSInteger expiredInDays = 4; 

    // Calculate the Date. 
    // Get the Date 

    NSDate * now = [NSDate date]; 

    NSTimeInterval tiNow = [now timeIntervalSinceReferenceDate]; 
    tiNow = tiNow + 60*60*24*expiredInDays; 
    NSDate * expires = [NSDate dateWithTimeIntervalSinceReferenceDate:tiNow]; 

    NSDateComponents *countdown = [[NSCalendar currentCalendar] 
           components:(NSCalendarUnitDay) 
              // | NSCalendarUnitHour | NSCalendarUnitMinute | NSCalendarUnitSecond) 
           fromDate:[NSDate date] 
           toDate:expires 
           options:0]; 

    NSString *myDays = [NSString stringWithFormat:@"%ld", (long)[countdown day]]; 

    [[NSUserDefaults standardUserDefaults] setObject:myDays forKey:@"Expired_Date"]; 

}

后来，当我想要得到它：

NSDate *expiredDate = [[NSUserDefaults standardUserDefaults] objectForKey:@"Expired_Date"]; 
    doItLabel.text = [NSString stringWithFormat:@" f_ck me in %@ day(s)", expiredDate]; 

    //And for coloring label I add after 

    if ([NSDate date] > expiredDate) doItLabel.textColor = [UIColor redColor];