When does UITableView content size update with row insert/delete animation

cocoa-touch, ios, uitableview

Solution

Unfortunately, I haven't been able to find a good way to update the contentSize when adding/deleting rows from a UITableView either, but I did find a way to calculate what it will be if you know the index paths of the cells you are adding/removing.

Using the index path of the modified rows, you can calculate the heights of the respective cells with the tableView:heightForRowAtIndexPath: method and add it to the current content size height of the table view. Here's an example if you're adding just one row:

[self.tableView insertRowsAtIndexPaths:@[indexPathOfNewRow] withRowAnimation:UITableViewRowAnimationAutomatic];
CGFloat newCellHeight = [self tableView:self.tableView heightForRowAtIndexPath:indexPathOfNewRow];
CGFloat newContentSizeHeight = self.tableView.contentSize.height + newCellHeight

Problem

I am curious when the UITableView's content size is updated after doing an insert/delete animation call. I figured it would be like most [UIView animation...] blocks in that the frame size/content size would be updated immediately even though the animation hasnt completed, but it does not seem to be that way. Any ideas?

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