Calendar Dates in TableView with Infinite Scrolling - ios

Question

I am trying to implement to show the calendar dates in TableViewCell. I am able to achieved the filled with current year. But As soon I hit the bottom of the table I need to populate next year and if I hit at top of TableView then previous year should be populated.
Pasting code which I have implemented.
- (void)fillDatesWithCalendarUnit:(NSCalendarUnit)unit withDate:(NSDate*)date
{
NSDate *today = date;
NSCalendar *calendar = [NSCalendar autoupdatingCurrentCalendar];
NSDate *beginning;
NSTimeInterval length;
[calendar rangeOfUnit:unit startDate:&beginning interval:&length forDate:today];
NSDate *end = [beginning dateByAddingTimeInterval:length-1];
[self fillDatesFromDate:beginning toDate:end];
}
- (void)fillDatesFromDate:(NSDate *)fromDate toDate:(NSDate *)toDate
{
NSAssert([fromDate compare:toDate] == NSOrderedAscending, #"toDate must be after fromDate");
NSDateComponents *days = [[NSDateComponents alloc] init];
NSCalendar *calendar = [NSCalendar autoupdatingCurrentCalendar];
NSInteger dayCount = 0;
while(YES){
[days setDay:dayCount++];
NSDate *date = [calendar dateByAddingComponents:days toDate:fromDate options:0];
if([date compare:toDate] == NSOrderedDescending) break;
[_dates addObject:date];
}
[self.tableView reloadData]; //_dates mutableArray
}
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return self.dates.count;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
AgendaCustomCell *cell = [self.tableView dequeueReusableCellWithIdentifier:#"Cell"];
cell.date.text = [NSString stringWithFormat:#"%#",_dates[indexPath.row]];
if (indexPath.row == _dates.count-1) {
NSLog(#"load more");
NSDate *tomorrow = [NSDate dateWithTimeInterval:(48*60*60) sinceDate:_dates[indexPath.row]];
NSLog(#"last daye - %# ,tomorrow - %#",_dates[indexPath.row],tomorrow);
[self fillDatesWithCalendarUnit:NSCalendarUnitYear withDate:_dates[indexPath.row]];
}
return cell;
}

Answer 1

I have implemented the logic for show infinite future dates on scrolling.
- (void)viewDidLoad {
[super viewDidLoad];
_dates = [NSMutableArray new];
[self fillCurrentYear];
}
- (void)fillCurrentYear
{
[self fillDatesWithCalendarUnit:NSCalendarUnitYear withDate:[NSDate new
] isLoadMore:NO];
}
pragma mark Private methods
- (void)fillDatesWithCalendarUnit:(NSCalendarUnit)unit withDate:(NSDate*)date isLoadMore:(BOOL)isBool
{
NSCalendar *calendar = [NSCalendar autoupdatingCurrentCalendar];
NSDate *beginning;
NSTimeInterval length;
if (isBool) {
beginning = _dates[[_dates count]-1];
}
[calendar rangeOfUnit:unit startDate:&beginning interval:&length forDate:date];
NSDate *end = [beginning dateByAddingTimeInterval:length-1];
[self fillDatesFromDate:beginning toDate:end];
}
- (void)fillDatesFromDate:(NSDate *)fromDate toDate:(NSDate *)toDate
{
NSAssert([fromDate compare:toDate] == NSOrderedAscending, #"toDate must be after fromDate");
// NSMutableArray *dates = [[NSMutableArray alloc] init];
NSDateComponents *days = [[NSDateComponents alloc] init];
NSCalendar *calendar = [NSCalendar autoupdatingCurrentCalendar];
NSInteger dayCount = 0;
while(YES){
[days setDay:dayCount++];
NSDate *date = [calendar dateByAddingComponents:days toDate:fromDate options:0];
if([date compare:toDate] == NSOrderedDescending) break;
[_dates addObject:date];
}
// _dates = dates;
[self.tableView reloadData];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
AgendaCell *cell = [self.tableView dequeueReusableCellWithIdentifier:#"Cell"];
cell.date.text = [NSString stringWithFormat:#"%#",_dates[indexPath.row]];
if (indexPath.row == _dates.count-1) {
NSLog(#"load more");
NSDate *tomorrow = [NSDate dateWithTimeInterval:(48*60*60) sinceDate:_dates[indexPath.row]];
NSLog(#"last daye - %# ,tomorrow - %#",_dates[indexPath.row],tomorrow);
[self fillDatesWithCalendarUnit:NSCalendarUnitYear withDate:tomorrow isLoadMore:YES];
}
return cell;
}