UITableviewCell automatic sizing based on label not working - objective-c

Question

UITableview cells are returning heights that don't really correlate to their text.
I have been dealing with a rather annoying bug where xcode returns incorrect heights for cells and just in general is return pixels heights for elements in cells that are terribly inconsistent.
I thought I could implement the methods below to clean things up, but they turned out just to make things worse.
The first image in the google doc is what my cells look like when I use these methods. Please tell me any ideas you have to fix them. The crux of the problem is a special case which I have shown in the second image of the google doc.
The reason behind the special case and a deeper discussion of the reason it occurs is in the google doc. Here's the google doc link:
https://docs.google.com/document/d/1tT43nE-1Wq8leRIaoQ29S0aQhZUWP88kIX3WlG_RcOg/edit?usp=sharing
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
if (indexPath.section==0) { //postcell
return 500.0; //TODO add some autolayout stuff for this case...
} else { //comment cell
UIFont * font=[UIFont fontWithName:#"Helvetica Neue" size:13.0];
NSIndexPath *adjustedIndexPath = [NSIndexPath indexPathForRow:indexPath.row inSection:indexPath.section-1];
BRComment *comment = [self.commentsController objectAtIndexPath:adjustedIndexPath];
CGRect screenRect = [[UIScreen mainScreen] bounds];
CGFloat screenWidth = screenRect.size.width;
//CommentCell * commentCell=(CommentCell *)[self.tableView cellForRowAtIndexPath:indexPath];
CGSize labelHeight = [self heigtForCellwithString:comment.body andLabelWidth:screenWidth-78.0 withFont:font];
return labelHeight.height; // the return height + your other view height
}
}
-(CGSize)heigtForCellwithString:(NSString *)stringValue andLabelWidth:(CGFloat)labelWidth withFont:(UIFont *)font{
CGSize constraint = CGSizeMake(labelWidth,9999); // Replace 300 with your label width //TODO replace
NSDictionary *attributes = #{NSFontAttributeName: font};
CGRect rect = [stringValue boundingRectWithSize:constraint
options: (NSStringDrawingUsesLineFragmentOrigin|NSStringDrawingUsesFontLeading)
attributes:attributes
context:nil];
return rect.size;
}

Answer 1

iOS 8 introduces the super handy UITableViewAutomaticDimension const to UITableView. To get cells to size themselves automatically simply return UITableViewAutomaticDimension from both -tableView:heightForRowAtIndexPath: and -tableView:estimatedHeightForRowAtIndexPath:.
- (CGFloat)tableView:(UITableView *)tableView estimatedHeightForRowAtIndexPath:(NSIndexPath *)indexPath
{
return UITableViewAutomaticDimension;
}
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
return UITableViewAutomaticDimension;
}
Voila, your cells should be sized correctly. Note this'll also take into account cell layoutMargins and indentationWidth/indentationLevel if you need to use those.