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

You said that you have a UITableView with differing heights. Have you set the reuse identifier to the same thing for all of the cells? It could be that older cells with their height already set are being reused. If this is the problem, you should resize the cell again when it's being reused.

Answer 2

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!

Answer 3

Check out this post http://stackoverflow.com/questions/50467/how-do-i-size-a-uitextview-to-its-content

It looks like textView.contentSize.height should work (with the caveat that the the correct contentSize is only available after the UITextView has been added to the view with addSubview)