How to load more data in UITableView after scrolling - objective-c

Question

I have Thrift server, I can get information and load them in my UITableView, at the first I load 10 rows, and after scrolling to the end each time I want to load 10 more rows(with information) but it's never work for me,
would you please help me in this implementation,
Thanks in advance!
Here is my numberOfRowsInSection method
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return _notes.count;
}
my method scrollViewDidScroll
-(void)scrollViewDidScroll: (UIScrollView*)scrollView
{
float scrollViewHeight = scrollView.frame.size.height;
float scrollContentSizeHeight = scrollView.contentSize.height;
float scrollOffset = scrollView.contentOffset.y;
if (scrollOffset == 1)
{
[self.tableView setContentOffset:CGPointMake(0, 44)];
}
else if (scrollOffset + scrollViewHeight == scrollContentSizeHeight)
{
// I don't know what should I put here
NSLog(#"%# we are at the end", _notes); //==> _notes is null
//we are at the end, it's in the log each time that scroll, is at the end
}
Here is how I connect to the server
- (void)viewDidAppear:(BOOL)animated{
[super viewDidAppear:YES];
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT,
(unsigned long)NULL), ^(void) {
NSURL *url = [NSURL URLWithString:BASE_URL];
THTTPClient *transport = [[THTTPClient alloc] initWithURL:url];
TBinaryProtocol *protocol = [[TBinaryProtocol alloc]
initWithTransport:transport
strictRead:YES
strictWrite:YES];
server = [[thrift_Client alloc] initWithProtocol:protocol];
_notes = [server get_notes:10 offset:0 sort_by:0 search_for:result];
__weak NotesTable *weakSelf = self;
dispatch_async(dispatch_get_main_queue(), ^{
[weakSelf.notesTable reloadData];
});
});
[self.view setNeedsDisplay];
}

Answer 1

Use SVPullToRefresh, it offers nice encapsulation. Add the library and register your UITableView with
[tableView addInfiniteScrollingWithActionHandler:^{
// prepend data to dataSource, insert cells at top of table view
// call [tableView.pullToRefreshView stopAnimating] when done
}];

Answer 2

Hi use this it works perfectly for me try this...
- (void)scrollViewDidScroll:(UIScrollView *)aScrollView
{
CGPoint offset = aScrollView.contentOffset;
CGRect bounds = aScrollView.bounds;
CGSize size = aScrollView.contentSize;
UIEdgeInsets inset = aScrollView.contentInset;
float y = offset.y + bounds.size.height - inset.bottom;
float h = size.height;
float reload_distance = 10;
if(y > h + reload_distance)
{
//Put your load more data method here...
}
}
}

Answer 3

You should put your request. The one that is executing on viewdidappear.. remove from viewdidappear put it inside a method. Then call this method from viewdidappear and from this place you put the log and instead of your implementation of didscroll this is one is better
- (void)scrollViewDidScroll: (UIScrollView *)scroll {
NSInteger currentOffset = scroll.contentOffset.y;
NSInteger maximumOffset = scroll.contentSize.height - scroll.frame.size.height;
// Change 10.0 to adjust the distance from bottom
if (maximumOffset - currentOffset <= 10.0) {
[self methodThatAddsDataAndReloadsTableView];
}
}