iOS-简单日历

效果图：

date.png

简单代码：

#define collectionH (kMainScreenWidth-20)*6/7
#define itemMargin 0
NSString *const cellIdentifier = @"sttenceCell";

{
    UICollectionViewFlowLayout *_flowLayout;
}
@ppoperty(nonstick,strong) UIView *contentView;
@property(nonatomic,strong) UIView *topView;
@property(nonatomic,strong) UICollectionView *collectionView;
@property(nonatomic,strong) UILabel *monthLabel;
@property(nonatomic,strong) UIButton *previousBtn;
@property(nonatomic,strong) UIButton *nextBtn;

@property(nonatomic,strong) NSArray *weekDayArray;
@property (nonatomic , strong) NSDate *date;
@property (nonatomic , strong) NSDate *today;

@property (weak, nonatomic) IBOutlet NSLayoutConstraint *contentViewHeight;

_contentViewHeight.constant = collectionH+84;
 NSDate *day = [NSDate date];
 self.today = day;
 self.date = self.today;
 NSString *thisMonth =[NSString stringWithFormat:@"%li-%.2ld",[self year:self.date],[self month:self.date]];

self.topView = [[UIView alloc] initWithFrame:CGRectMake(0,0, kMainScreenWidth, 84)];
    self.topView.backgroundColor = [UIColor whiteColor];
    [self.contentView addSubview:self.topView];
 self.previousBtn = [[UIButton alloc] initWithFrame:CGRectMake(10, 0, 40, 40)];
    [self.previousBtn setImage:[UIImage imageNamed:@"backGray"] forState:UIControlStateNormal];
    [self.previousBtn setImage:[UIImage imageNamed:@"backGray"] forState:UIControlStateHighlighted];
    [self.previousBtn addTarget:self action:@selector(previousBtnClick:) forControlEvents:UIControlEventTouchUpInside];
    [self.topView addSubview:self.previousBtn];
    self.nextBtn = [[UIButton alloc] initWithFrame:CGRectMake(kMainScreenWidth-10-40, 0, 40, 40)];
    [self.nextBtn setImage:[UIImage imageNamed:@"rightArrow"] forState:UIControlStateNormal];
    [self.nextBtn setImage:[UIImage imageNamed:@"rightArrow"] forState:UIControlStateHighlighted];
    [self.nextBtn addTarget:self action:@selector(nextBtnClick:) forControlEvents:UIControlEventTouchUpInside];
    [self.topView addSubview:self.nextBtn];
    self.monthLabel = [[UILabel alloc] initWithFrame:CGRectMake(10+40, 0, kMainScreenWidth-100, 40)];
    self.monthLabel.text = @"2018年2月";
    self.monthLabel.textColor = [UIColor lightGrayColor];
    self.monthLabel.textAlignment = NSTextAlignmentCenter;
    [self.topView addSubview:self.monthLabel];

    UIView *weekV = [[UIView alloc] initWithFrame:CGRectMake(0, 40, kMainScreenWidth, 44)];
    weekV.backgroundColor = RGB(234, 234, 234);
    [self.topView addSubview:weekV];
    _weekDayArray = @[@"周日",@"周一",@"周二",@"周三",@"周四",@"周五",@"周六"];
    CGFloat weekW = (kMainScreenWidth-20)/7;
    for (int i = 0; i< 7; i++) {
        UILabel *week = [[UILabel alloc] init];
        week.text = _weekDayArray[i];
        week.textColor = [UIColor darkGrayColor];
        week.textAlignment = NSTextAlignmentCenter;
        week.frame = CGRectMake(10+weekW*i, 0, weekW, 44);
        [weekV addSubview:week];
    }

    // collectionView
    _flowLayout = [[UICollectionViewFlowLayout alloc] init];
    UIView *collectView = [[UIView alloc] initWithFrame:CGRectMake(0,84, kMainScreenWidth, collectionH)];
    collectView.backgroundColor = [UIColor whiteColor];
    [self.contentView addSubview:collectView];
    self.collectionView = [[UICollectionView alloc] initWithFrame:CGRectMake(10,0, kMainScreenWidth-20, collectionH) collectionViewLayout:_flowLayout];
    //self.collectionView.backgroundColor = RGB(244, 244, 244);
    self.collectionView.backgroundColor = [UIColor whiteColor];
    [collectView addSubview:self.collectionView];

    self.collectionView.dataSource = self;
    self.collectionView.delegate = self;

    // 布局
    CGFloat topPading = itemMargin;
    CGFloat itemSpacing = itemMargin;
    CGFloat lineSpacing = itemMargin;
    CGFloat leftPading  = itemMargin;
    CGFloat itemW = (kMainScreenWidth-20-8*itemMargin)/7;
    CGFloat itemH = itemW;
    _flowLayout.itemSize = CGSizeMake(itemW, itemH);
    _flowLayout.minimumInteritemSpacing = itemSpacing;
    _flowLayout.minimumLineSpacing = lineSpacing;
    _flowLayout.sectionInset = UIEdgeInsetsMake(topPading, leftPading, topPading, leftPading);
    [_collectionView setCollectionViewLayout:_flowLayout animated:YES];
    //注册cell
    [_collectionView registerNib:[UINib nibWithNibName:@"GEAttendanceCell" bundle:nil] forCellWithReuseIdentifier:attenceCellIdentifier];

- (void)setDate:(NSDate *)date
{
    _date = date;
    [_monthLabel setText:[NSString stringWithFormat:@"%li-%.2ld",[self year:date],[self month:date]]];
}

#pragma -mark collectionView delegate
- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView
{
    return 1;
}

- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section
{
    NSInteger daysInThisMonth = [self totaldaysInMonth:_date];
    NSInteger firstWeekday = [self firstWeekdayInThisMonth:_date];
    NSUInteger count = daysInThisMonth+firstWeekday;
    return count;
}

- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{

    GEAttendanceCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:attenceCellIdentifier forIndexPath:indexPath];

    NSInteger daysInThisMonth = [self totaldaysInMonth:_date];
    NSInteger firstWeekday = [self firstWeekdayInThisMonth:_date];
    NSInteger day = 0;
    NSInteger i = indexPath.row;

    if (i < firstWeekday) {
        cell.contentView.hidden = YES;
        cell.layer.borderWidth=0.0;
    }else if (i > firstWeekday + daysInThisMonth - 1){
        //cell.contentVIew.hidden = YES;
    }else{
        cell.contentView.hidden = NO;

        day = i - firstWeekday + 1;
        [cell.dateTime setText:[NSString stringWithFormat:@"%li",day]];
        [cell.dateTime setTextColor:[UIColor darkGrayColor]];

        //NSUInteger inx = indexPath.row-firstWeekday;
        //cell.attencesModel = _attendaceLsit[inx];
       // cell.markLabel.backgroundColor = [UIColor whiteColor];
        
        //this month
        if ([_today isEqualToDate:_date]) {
            if (day == [self day:_date]) {
                cell.dateTime.backgroundColor = RGB(0, 207, 151);
                cell.dateTime.layer.cornerRadius=10;
                cell.dateTime.layer.masksToBounds=YES;

            } else if (day > [self day:_date]) {
                [cell.dateTime setTextColor:[UIColor lightGrayColor]];
            }
        } else if ([_today compare:_date] == NSOrderedAscending) {
            [cell.dateTime setTextColor:[UIColor lightGrayColor]];
        }

        cell.layer.borderColor=RGB(244, 244, 244).CGColor;
        cell.layer.borderWidth=0.3;
    }

    return cell;

}

- (BOOL)collectionView:(UICollectionView *)collectionView shouldSelectItemAtIndexPath:(NSIndexPath *)indexPath
{

    NSInteger daysInThisMonth = [self totaldaysInMonth:_date];
    NSInteger firstWeekday = [self firstWeekdayInThisMonth:_date];

    NSInteger day = 0;
    NSInteger i = indexPath.row;

    if (i >= firstWeekday && i <= firstWeekday + daysInThisMonth - 1) {
        day = i - firstWeekday + 1;

        //this month
        if ([_today isEqualToDate:_date]) {
            if (day <= [self day:_date]) {
                return YES;
            }
        } else if ([_today compare:_date] == NSOrderedDescending) {
            return YES;
        }
    }

    return NO;
}

#pragma mark btnClick
- (void)previousBtnClick:(UIButton *)btn
{
    self.previousBtn.enabled = NO;
    [self performSelector:@selector(previousbtn:) withObject:nil afterDelay:1.0f];
    self.date = [self lastMonth:self.date];
    //NSString *pTime =[NSString stringWithFormat:@"%li%.2ld-%ld",[self year:self.date],[self month:self.date],[self totaldaysInMonth:self.date]];
    NSString *pTime =[NSString stringWithFormat:@"%li%.2ld",[self year:self.date],[self month:self.date]];

    [self loadHttpDataWithAttendanceDate:pTime];

}
- (void)nextBtnClick:(UIButton *)btn
{
    self.nextBtn.enabled = NO;
    [self performSelector:@selector(nextbtn:) withObject:nil afterDelay:1.0f];
    self.date = [self nextMonth:self.date];
    NSString *nTime =[NSString stringWithFormat:@"%li%.2ld",[self year:self.date],[self month:self.date]];

    [self loadHttpDataWithAttendanceDate:nTime];

}
- (void)previousbtn:(UIButton *)btn
{
    self.previousBtn.enabled = YES;
}
- (void)nextbtn:(UIButton *)btn
{
    self.nextBtn.enabled = YES;
}

#pragma mark - date
- (NSInteger)day:(NSDate *)date{
    NSDateComponents *components = [[NSCalendar currentCalendar] components:(NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay) fromDate:date];
    return [components day];
}
- (NSInteger)month:(NSDate *)date{
    NSDateComponents *components = [[NSCalendar currentCalendar] components:(NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay) fromDate:date];
    return [components month];
}
- (NSInteger)year:(NSDate *)date{
    NSDateComponents *components = [[NSCalendar currentCalendar] components:(NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay) fromDate:date];
    return [components year];
}
- (NSInteger)firstWeekdayInThisMonth:(NSDate *)date{
    NSCalendar *calendar = [NSCalendar currentCalendar];

    [calendar setFirstWeekday:1];//1.Sun. 2.Mon. 3.Thes. 4.Wed. 5.Thur. 6.Fri. 7.Sat.
    NSDateComponents *comp = [calendar components:(NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay) fromDate:date];
    [comp setDay:1];
    NSDate *firstDayOfMonthDate = [calendar dateFromComponents:comp];

    NSUInteger firstWeekday = [calendar ordinalityOfUnit:NSCalendarUnitWeekday inUnit:NSCalendarUnitWeekOfMonth forDate:firstDayOfMonthDate];
    return firstWeekday - 1;
}
- (NSInteger)totaldaysInThisMonth:(NSDate *)date{
    NSRange totaldaysInMonth = [[NSCalendar currentCalendar] rangeOfUnit:NSCalendarUnitDay inUnit:NSCalendarUnitMonth forDate:date];
    return totaldaysInMonth.length;
}
- (NSInteger)totaldaysInMonth:(NSDate *)date{
    NSRange daysInLastMonth = [[NSCalendar currentCalendar] rangeOfUnit:NSCalendarUnitDay inUnit:NSCalendarUnitMonth forDate:date];
    return daysInLastMonth.length;
}
- (NSDate *)lastMonth:(NSDate *)date{
    NSDateComponents *dateComponents = [[NSDateComponents alloc] init];
    dateComponents.month = -1;
    NSDate *newDate = [[NSCalendar currentCalendar] dateByAddingComponents:dateComponents toDate:date options:0];
    return newDate;
}
- (NSDate*)nextMonth:(NSDate *)date{
    NSDateComponents *dateComponents = [[NSDateComponents alloc] init];
    dateComponents.month = +1;
    NSDate *newDate = [[NSCalendar currentCalendar] dateByAddingComponents:dateComponents toDate:date options:0];
    return newDate;
}