5

I am trying to limit the text input into a UITextView in cocoa-touch. I really want to limit the amount of rows rather than the number of characters. So far I have this to count the amount of rows:

- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text { if([text isEqualToString:@"\n"]) { rows++; } NSLog(@"Rows: %i", rows); return YES; } 

However this doesn't work if the line is automatically wrapped rather than the user pressing the return key. Is there a way to check if the text was wrapped similar to checking for "\n"?

Thanks.

1 Answer 1

14

Unfortunately, using NSString -stringWithFont:forWidth:lineBreakMode: doesn't work - which ever wrap mode you choose, the text wraps with a width that is less than the current width, and the height becomes 0 on any overflow lines. To get a real figure, fit the string into a frame that is taller than the one you need - then you'll get a height that is greater than your actual height.

Note my fudge in this (subtracting 15 from the width). This might be something to do with my views (I have one within another), so you might not need it.

- (BOOL)textView:(UITextView *)aTextView shouldChangeTextInRange:(NSRange)aRange replacementText:(NSString*)aText { NSString* newText = [aTextView.text stringByReplacingCharactersInRange:aRange withString:aText]; // TODO - find out why the size of the string is smaller than the actual width, so that you get extra, wrapped characters unless you take something off CGSize tallerSize = CGSizeMake(aTextView.frame.size.width-15,aTextView.frame.size.height*2); // pretend there's more vertical space to get that extra line to check on CGSize newSize = [newText sizeWithFont:aTextView.font constrainedToSize:tallerSize lineBreakMode:UILineBreakModeWordWrap]; if (newSize.height > aTextView.frame.size.height) { [myAppDelegate beep]; return NO; } else return YES; } 
Sign up to request clarification or add additional context in comments.

2 Comments

Hi Jane - I know this post is rather old, but it appears that this is a very similar problem to the one I am facing [here] (stackoverflow.com/questions/5605226/…). Is this the problem you're describing here or is your solution for a slightly different problem?
In iOS 7 I found the following margins and padding values for UITextView that may be the cause you need to use "tallerSize": textContainerInset and textContainer.lineFragmentPadding. See UITextView reference

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.