UITableView, scroll down to reboot?

Question

I have a UITableView with cells that are dynamically updated. Everything works fine when tableview.reload is tableview.reload (see below) to update the cells in the table. I would like the table to scroll down to display new entries.

 - (void)reloadTable:(NSNotification *)notification { NSLog(@"RELOAD TABLE ..."); [customTableView reloadData]; // Scroll to bottom of UITable here .... } 

I planned to use scrollToRowAtIndexPath:atScrollPosition:animated: but then noticed that I did not have access to indexPath .

Does anyone know how to do this, or a delegate callback that I could use?

Answer 1

Using:

 NSIndexPath* ipath = [NSIndexPath indexPathForRow: cells_count-1 inSection: sections_count-1]; [tableView scrollToRowAtIndexPath: ipath atScrollPosition: UITableViewScrollPositionTop animated: YES]; 

Or you can specify the index of the section manually (if one section => index = 0).

Answer 2

Another solution is to flip the table vertically and flip each cell vertically:

Apply the transform to a UITableView when initializing:

 tableview.transform = CGAffineTransformMakeScale(1, -1); 

and in cellForRowAtIndexPath:

 cell.transform = CGAffineTransformMakeScale(1, -1); 

This way you don't need workarounds for scrolling, but you will need to think a bit about contentInsets / contentOffsets and header / footer interactions.

Answer 3

 -(void)scrollToBottom{ [self.tableView scrollRectToVisible:CGRectMake(0, self.tableView.contentSize.height - self.tableView.bounds.size.height, self.tableView.bounds.size.width, self.tableView.bounds.size.height) animated:YES]; } 

Answer 4

 //In swift var iPath = NSIndexPath(forRow: self.tableView.numberOfRowsInSection(0)-1, inSection: self.tableView.numberOfSections()-1) self.tableView.scrollToRowAtIndexPath(iPath, atScrollPosition: UITableViewScrollPosition.Bottom, animated: true) 

Answer 5

This is another solution that works well in my case when the cell height is large.

 - (void)scrollToBottom { CGPoint bottomOffset = CGPointMake(0, _bubbleTable.contentSize.height - _bubbleTable.bounds.size.height); if ( bottomOffset.y > 0 ) { [_bubbleTable setContentOffset:bottomOffset animated:YES]; } } 

Answer 6

Since this is something you might want to use very often, I suggest you create a class extension in a UITableView:

 extension UITableView { func scrollToBottom(animated: Bool = true) { let section = self.numberOfSections if section > 0 { let row = self.numberOfRowsInSection(section - 1) if row > 0 { self.scrollToRowAtIndexPath(NSIndexPath(forRow: row - 1, inSection: section - 1), atScrollPosition: .Bottom, animated: animated) } } } } 

Answer 7

Swift 3

For anyone here trying to figure out how to solve this problem, the key is to call .layoutIfNeeded() after .reloadData() :

 tableView.reloadData() tableView.layoutIfNeeded() tableView.setContentOffset(CGPoint(x: 0, y: tableView.contentSize.height - tableView.frame.height), animated: false) 

I worked with several sections in a UITableView and it worked well.

Answer 8

Expansion

it's better to do in a UIScrollView instead of a UITableView, so it works on scrollView, tableView, collectionView (vertical), UIWebView (internal scroll view), etc.

 public extension UIScrollView { public func scrollToBottom(animated animated: Bool) { let rect = CGRectMake(0, contentSize.height - bounds.size.height, bounds.size.width, bounds.size.height) scrollRectToVisible(rect, animated: animated) } } 

Answer 9

Fot swift 5

 extension UITableView { func scrollToBottom(animated: Bool = true) { let section = self.numberOfSections if section > 0 { let row = self.numberOfRows(inSection: section - 1) if row > 0 { self.scrollToRow(at: IndexPath(row: row-1, section: section-1), at: .bottom, animated: animated) } } } } 

Answer 10

This is the best way.

 - (void)scrollToBottom { CGFloat yOffset = 0; if (self.tableView.contentSize.height > self.tableView.bounds.size.height) { yOffset = self.tableView.contentSize.height - self.tableView.bounds.size.height; } [self.tableView setContentOffset:CGPointMake(0, yOffset) animated:NO]; } 

Answer 11

try this code, it can help you:

  self.tableView.reloadData() DispatchQueue.main.asyncAfter(deadline: DispatchTime.now()+0.1, execute: { let indexPath = IndexPath(row: self.dateSource.count-1, section: 0) self.tableView.scrollToRow(at: indexPath, at: UITableViewScrollPosition.bottom, animated: true) }) 

Answer 12

Swift 5

  func scrollToBottom() { let section = self.tableView.numberOfSections let row = self.tableView.numberOfRows(inSection: self.tableView.numberOfSections - 1) - 1; guard (section > 0) && (row > 0) else{ // check bounds return } let indexPath = IndexPath(row: row-1, section: section-1) self.tableView.scrollToRow(at: indexPath, at: .top, animated: true) } 

I do not agree that we should use cells_count , sections_count , self.dateSource.count , etc. Instead, a delegate would be better.