How to find the position of the last text line in a multiline UILabel or otherwise have UILabel have 0 padding - ios7

Question

I have a UILabel that has both -numberOfLines set to 3 and text-size auto shrink and I need to align another UIView to this UILabel's last line of text. That is, I might need to align to the y position of line 0, 1 or 2, depending on the text inside the label (and the distance between these lines of text may vary depending on whether the text is long enough that it triggered font resizing).
But:
UILabel doesn't expose a contentSize
the label's bounds extend past the last line of text (there seems to be a content inset), so aligning to the bounds won't work.
subclassing UILabel and doing something like this:
- (void)drawTextInRect:(CGRect)rect {
UIEdgeInsets insets = {0., 0., -30., 0.};
return [super drawTextInRect:UIEdgeInsetsInsetRect(rect, insets)];
}
just happens to work for the case where I have 3 lines and the font size was auto shrunk, but I still can'r figure out a generic way of subtracting insets for the general case, regardless of text size. And I don't seem to be able to use -boundingRectWithSize:options:context: either: it either returns a single line equivalent rect or, If I play around with the options, a a rect the same size of the original label (that is, including the extra insets I'm trying to get rid of). Mind you, the idea behind removing any insets is that if I have no way of knowing where the last line of text is, at least I can remove any insets in the label so that the last line of text aligns with the label's bounds.origin.y + bounds.size.height.
Any thoughts?

Answer 1

I don't know if the problem was that originally I was using boundingRectWithSize on non-attributed text or what but now this seems to work:
NSString *text = <get text from CoreData>;
NSAttributedString *attributedText = [[NSAttributedString alloc] initWithString:text attributes:#{NSFontAttributeName: self.titleLabel.font}];
CGRect rect = [attributedText boundingRectWithSize:self.titleLabel.frame.size
options:NSStringDrawingUsesLineFragmentOrigin
context:nil];
if (!rect.size.height || rect.size.height > self.titleLabel.frame.size.height) {
attributedText = [[NSAttributedString alloc] initWithString:text attributes:#{NSFontAttributeName: [UIFont boldSystemFontOfSize:self.titleLabel.font.pointSize * self.titleLabel.minimumScaleFactor]}];
rect = [attributedText boundingRectWithSize:self.titleLabel.frame.size
options:NSStringDrawingUsesLineFragmentOrigin
context:nil];
}
self.titleLabel.frame = rect;
self.titleLabel.attributedText = attributedText;
While this doesn't really find the position of the bottom of the last line of text in the UILabel (the label still adds some padding at the bottom... not sure if to account for descenders), it adjusts the label's bounds close enough to the bottom that I can at least align based on bounds.origin.y + bounds.size.height and it looks good enough.