模拟电子表的功能

- (void)viewDidLoad
{
    [superviewDidLoad];
    _timeLabel.textColor = [UIColorredColor];
    _timeLabel.font = [UIFontsystemFontOfSize:13];
    _timeLabel.backgroundColor = [UIColorcolorWithRed:137.0/255.0green:109.0/255.0blue:164.0/255.0alpha:1];
    [self setTime];
    [NSTimer scheduledTimerWithTimeInterval:1target:selfselector:@selector(timerAction:)userInfo:nilrepeats:YES];
}

- (void)timerAction:(NSTimer *)timer {
    [self setTime];
}

- (void)setTime {
    NSDate  *date = [NSDatedate];
    NSDateFormatter *formatter = [[NSDateFormatteralloc]
init];
//    [formatter setAMSymbol:@"AM"];
//    [formatter setPMSymbol:@"PM"];
    [formatter setDateFormat:@"yyyy-MM-dd HH:mm:ss"];
    _timeLabel.text = [NSStringstringWithFormat:@"         %@    正在直播.....",[formatterstringFromDate:date]];
}