CGRect mainBounds = [[UIScreen mainScreen] bounds]; UIFont *font = [UIFont systemFontOfSize:15.0f]; CGRect locationBtnFrame = self.locationButton.frame; CGFloat maxWidth = mainBounds.size.width - locationBtnFrame.origin.x; CGSize size = CGSizeMake(maxWidth, MAXFLOAT); CGSize theStringSize = [theText sizeWithFont:font constrainedToSize:size lineBreakMode:self.locationButton.lineBreakMode]; self.locationButton.frame = CGRectMake(locationBtnFrame.origin.x, locationBtnFrame.origin.y, theStringSize.width, locationBtnFrame.size.height);
原文:http://blog.csdn.net/wang_lichun/article/details/44673683