how to scroll tableview after inserting a row at the bottom correctly?

Question

Here is the code I use:

//inserting a row at the bottom first
_numberOfRecords++;
[_tableView beginUpdates];
[_tableView insertRowsAtIndexPaths:@[[NSIndexPath indexPathForRow:_numberOfRecords-1 inSection:0]] withRowAnimation:UITableViewRowAnimationBottom];
[_tableView endUpdates];
//clear text
_inputField.text = @"";

//then scroll to bottom
CGPoint bottomOffset = CGPointMake(0, _tableView.contentSize.height + 44.0 + _tableView.contentInset.top - _tableView.bounds.size.height);
NSLog(@"%f", _tableView.contentSize.height + 44.0 + _tableView.contentInset.top - _tableView.bounds.size.height);
[_tableView setContentOffset:bottomOffset animated:YES];

This would scroll the tableview in a very strange way. But if I put the scrolling code BEFORE the insertion, it works fine except that it ignores the latest inserted row. That is, it scrolls to the second last row instead of scrolling to the very last row (of course, because it scrolls before inserting a new roll.)

So I believe this code has no problem of the position where it should scroll to. The problem probably comes from row insertion to tableview. It violates the animation of scrolling the table view.

I am doing this to make a chatting view. Each time the user sends or receives a message, I insert a row containing the message to a table view, and scrolls it to the bottom. That's why I use tableView here. I tried to use scrollView with label, it works fine, but tableView seems more popular in a chatting view.

I was thinking to use scrollView or tableView, and I found the built-in message app of Apple is using a tableView, so I adopt tableView. Let me know if a scrollView with Label is better than a tableView.

Anyway, how can I scroll a tableView to the bottom after inserting a new row?

Answer 1

Try using UITableView's scrollToRowAtIndexPath::

[self.tableView scrollToRowAtIndexPath: atScrollPosition: animated:];