日历

画日历。最简单的日历。通过NSCalendar和UICollectionView来操作。

1.主要的内容是获取。当前月份的范围。上一个月的遗留天数。下一月空出的天数。核心代码。

 1 - (void)FF_CalendarDataCode
 2 {
 3     /// 获取当前月份的范围
 4     NSCalendar *calendar = [NSCalendar currentCalendar];
 5     NSRange currentRange = [calendar rangeOfUnit:NSCalendarUnitDay inUnit:NSCalendarUnitMonth forDate:[NSDate date]];
 6     NSDateComponents *currentComponents = [calendar components:NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay fromDate:[NSDate date]];
 7     /// 获取当月的第一天是周几
 8     currentComponents.day = 1;
 9     NSInteger startWeak = [calendar component:NSCalendarUnitWeekday fromDate:[calendar dateFromComponents:currentComponents]];
10     /// 获取当月的最后一天是周几（从周日-周为0-7）
11     currentComponents.day += currentRange.length - 1;
12     NSInteger endWeak = [calendar component:NSCalendarUnitWeekday fromDate:[calendar dateFromComponents:currentComponents]];
13     /// 获取上个月份范围
14     NSDateFormatter *lastFormatter= [[NSDateFormatter alloc] init];
15     lastFormatter.dateFormat = @"yyyy-MM-dd";
16     NSCalendar *lastCanlendar = [NSCalendar currentCalendar];
17     NSDateComponents *lastComponents = [lastCanlendar components:NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay fromDate:[NSDate date]];
18     if (lastComponents.month > 1) {
19         lastComponents.month -= 1;
20     }else {
21         lastComponents.year -= 1;
22         lastComponents.month = 12;
23     }
24     lastComponents.day = 1;
25     NSRange lastMonthRange = [lastCanlendar rangeOfUnit:NSCalendarUnitDay inUnit:NSCalendarUnitMonth forDate:[lastFormatter dateFromString:[NSString stringWithFormat:@"%ld-%02ld-%02ld", lastComponents.year, lastComponents.month, lastComponents.day]]];
26     /// 获取上个月剩余的天数
27     NSMutableArray *lastMonthArr = [NSMutableArray arrayWithCapacity:0];
28     for (NSUInteger i = lastMonthRange.length - startWeak + 2; i <= lastMonthRange.length; i++) {
29         [lastMonthArr addObject:[NSString stringWithFormat:@"%02ld", i]];
30     }
31     /// 获取本月的天数
32     NSMutableArray *currentMonthArr = [NSMutableArray arrayWithCapacity:0];
33     for (NSUInteger i = 1; i <= currentRange.length; i ++) {
34         [currentMonthArr addObject:[NSString stringWithFormat:@"%02ld", i]];
35     }
36     /// 获取下个月需要展示的天数
37     NSMutableArray *nextMonthArr = [NSMutableArray arrayWithCapacity:0];
38     for (NSUInteger i = 1; i <= 7 - endWeak; i++) {
39         [nextMonthArr addObject:[NSString stringWithFormat:@"%02ld", i]];
40     }
41     /// 需要展示的数据
42     NSMutableArray *dataArray = [NSMutableArray arrayWithArray:lastMonthArr];
43     [dataArray addObjectsFromArray:currentMonthArr];
44     [dataArray addObjectsFromArray:nextMonthArr];
45     NSLog(@"-------\n%@\n%@\n%@\n", lastMonthArr, currentMonthArr, nextMonthArr);
46 }