Question

我是ios开发的新手。我正在使用uipickerview制作自定义日期选择器。我有datesArray用作uipickerview的数据源。

我想知道如何仅显示标签：今天，明天，周五，周六，周日，周一，本周的周二和休息日期格式为“EEE，LLL d”。

我尝试了这段代码但是没有用。

for(int i=0;i<22;i++)
{
    NSDate *myDate = [NSDate dateWithTimeIntervalSinceNow:60 * 60 * 24 * i];
    NSDate *now=[NSDate date];
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    [dateFormatter setDateStyle:NSDateFormatterMediumStyle];
    [dateFormatter setDateFormat:@"EEE, LLL d"];
    if(myDate==now)
    {
        NSString *myDateString=@"today";
         [datesArray addObject:myDateString];
    }
    else
    {
    NSString *myDateString = [dateFormatter stringFromDate:myDate];

    [datesArray addObject:myDateString];
    }

}

Answer 1

试试这个。希望它有帮助

 NSString *dateFromWS = @"2013-10-16";//im taking it as static you have to take string coming from webservice

 for (int i = 0; i < 22; i++)
 {
    NSDateFormatter *dateFormatter1 = [[NSDateFormatter alloc] init];
    [dateFormatter1 setDateStyle:NSDateFormatterMediumStyle];
    [dateFormatter1 setDateFormat:@"yyyy-MM-dd"];
    NSDate *myDate = [NSDate dateWithTimeIntervalSinceNow:60 * 60 * 24 * i];
    NSDate *now = [dateFormatter1 dateFromString:dateFromWS];
    NSDate *tomorrow = [NSDate dateWithTimeInterval:60 * 60 * 24 * 1 sinceDate:now];
    //NSDate *dummy = [NSDate dateWithTimeInterval:60 * 60 * 24 * 1 sinceDate:now];
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    [dateFormatter setDateStyle:NSDateFormatterMediumStyle];
    [dateFormatter setDateFormat:@"EEE, LLL d"];
    NSString *loopDate = [dateFormatter stringFromDate:myDate];
    NSString *today = [dateFormatter stringFromDate:now];
    NSString *tomorrowString = [dateFormatter stringFromDate:tomorrow];
    if ([loopDate isEqualToString:today]) {
        [datesArray addObject:@"today"];
    } else if ([loopDate isEqualToString:tomorrowString]) {
       [datesArray addObject:@"tomorrow"]; 
    } else if ((i/7) < 1) {
        [datesArray addObject:[loopDate substringToIndex:3]];
    } else {
        [datesArray addObject:loopDate];
    }
 }

Answer 2

if(myDate==now)

比较2个指针而不是2个日期。您需要使用以下代码

if([myDate compare:now] == NSOrderedSame)

Answer 3

除了Simon的指针问题，您的日期将包含时间信息，因此永远不可能相同。可能是同一天但不是同一时间。您需要查找当天是否匹配。我是这样做的：

for(int i=0;i<22;i++)
{
    NSDate *myDate = [NSDate dateWithTimeIntervalSinceNow:60 * 60 * 24 * i];
    NSDate *myDateNoTime = nil;
    // Note: Create sysCal as a property so it is not being repeatedly recreated here
    [self.sysCal rangeOfUnit:NSDayCalendarUnit startDate:&myDateNoTime interval:nil forDate:myDate];
    NSDate *now=[NSDate date];
    NSDate *todayDateNoTime = nil;
    [self.sysCal rangeOfUnit:NSDayCalendarUnit startDate:&todayDateNoTime interval:nil forDate:now];

    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    [dateFormatter setDateStyle:NSDateFormatterMediumStyle];
    [dateFormatter setDateFormat:@"EEE, LLL d"];

    if([myDateNoTime isEqualToDate:todayDateNoTime])
    {
        NSString *myDateString=@"today";
         [datesArray addObject:myDateString];
    }
    else
    {
    NSString *myDateString = [dateFormatter stringFromDate:myDate];

    [datesArray addObject:myDateString];
    }

}

Answer 4

考虑到你的服务器日期要求，以及我认为处理选择器的更好方法，我会把它放在数据源方法中。

-(NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {

    NSString *resultString = nil;
    NSDate *myDate = [self dateForRow:row];
    NSDate *myDateNoTime = nil;
    // Note: Create sysCal as a property so it is not being repeatedly recreated here
    [self.sysCal rangeOfUnit:NSDayCalendarUnit startDate:&myDateNoTime interval:nil forDate:myDate];
    NSDate *now=[NSDate date];
    NSDate *todayDateNoTime = nil;
    [self.sysCal rangeOfUnit:NSDayCalendarUnit startDate:&todayDateNoTime interval:nil forDate:now];

    if([myDateNoTime isEqualToDate:todayDateNoTime])
    {
       resultString = @"Today";
    } else {
       // Note: using property for date formatter so I am not repeatedly creating here
       resultString = [self.dayFormatter stringFromDate:myDate];
    }

    return resultString;
}

确定行使用的日期：

-(NSDate *)dateFromRow:(NSInteger)inRow {
   NSDateComponents *daysToAdd = [[NSDateComponents alloc] init];
   [daysToAdd setCalendar:self.sysCal];
   NSInteger daysCalc = (-1 * (inRow -2));
   [daysToAdd setDay:daysCalc];
   NSDate *resultDate = nil;

   NSDate *calcDate = [self.sysCal dateByAddingComponents:daysToAdd 
                                                   toDate:self.myServerDate 
                                                  options:0];

   [self.sysCal rangeOfUnit:NSDayCalendarUnit startDate:&resultDate interval:nil forDate:calcDate];

   return resultDate;
}

我认为你已经按照自己的方式设置，但我认为你会发现这更加灵活，在服务器日期之前或之后的21天内没有限制。 Aircode，原谅任何拼写错误或语法错误。

Answer 5

Swift 4.0

for i in 0..<22 {
    var myDate = Date(timeIntervalSinceNow: 60 * 60 * 24 * i)
    var now = Date()
    var dateFormatter = DateFormatter()
    dateFormatter.dateStyle = .medium
    dateFormatter.dateFormat = "EEE, LLL d"

    if myDate == now {
       var myDateString = "today"
       datesArray.append(myDateString)
    } else {
       var myDateString: String = dateFormatter.string(from: myDate)
       datesArray.append(myDateString)
   }
}

使用UIPIckerView自定义DatePicker

5 个答案: