iphone - sizeWithFont doesn't give correct height for UITextView if there is a long string in the text being wrapped

Question

Is there a way to get the correct size of an NSString using:

- (CGSize)sizeWithFont:(UIFont *)font forWidth:(CGFloat)width lineBreakMode:(UILineBreakMode)lineBreakMode

that doesnt get thrown off by 2 or 3 hundred character strings. At the moment if I try to use this method on these long strings it incorrectly calculates them and I end up with lots of whitespace at the bottom of the UITextView.

I've tried using UILineBreakModeWordWrap and UILineBreakModeCharacterWrap.

the resizing is being done in

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
    CGFloat     result = 44.0f;
    NSString*   text = nil;
    CGFloat     width = 0;
    CGFloat     tableViewWidth;
    CGRect      bounds = [UIScreen mainScreen].bounds;

    tableViewWidth = bounds.size.width;


    width = tableViewWidth - 150;       

    text = stringWithLongWords;

    if (text) {
        CGSize      textSize = { width, 20000.0f };     
        CGSize      size = [text sizeWithFont:[UIFont systemFontOfSize:10.0f] constrainedToSize:textSize lineBreakMode:UILineBreakModeWordWrap];

        size.height += 50.0f;               
        result = MAX(size.height, 44.0f+30.0f); 
    }

    return result;
}

Answer 1

UITextView is not exactly like a UILabel wrapped in a UIScrollView. It has line spacing different from the font size and margins that sizeWithFont:constrainedToSize:linkBreakMode: doesn't account for.

Knowing your font size you might be able to calculate the # of lines and take line spacing into account. You can guess at the margins and try to trick sizeWithFont: to give a more useful answer.

The popular solutions seem to be:

• just use a UILabel if you don't need any UITextView functionality

• if you need hyperlinks, overlay UIButtons that look like hyperlinks over a UILabel

• use an off-screen UITextView and its sizeToFit method to get a real answer

I had no luck w/ the 3rd option but it sounds like it should work, so perhaps I did something wrong.

I'm going to try using a UILabel and overlaying buttons for hyperlinks. We'll see how that turns out.

If that fails, there is always the option taken by Loren Brichter (of Tweetie fame): draw everything into a UIView yourself using CoreGraphics.

Good luck!