AutoLayout row height miscalculating for NSAttributedString

Question

My app pulls HTML from an API, converts it into a NSAttributedString (in order to allow for tappable links) and writes it to a row in an AutoLayout table. Trouble i

Answer 1

You can replace this method to calculate the height of attributed string:

- (CGFloat)textViewHeightForAttributedText:(NSAttributedString*)text andFont:(UIFont *)font andWidth:(CGFloat)width {
CGFloat result = font.pointSize + 4;
if (text)
    result = (ceilf(CGRectGetHeight([text boundingRectWithSize:CGSizeMake(width, CGFLOAT_MAX) options:NSStringDrawingUsesLineFragmentOrigin | NSStringDrawingUsesFontLeading context:nil])) + 1);

return result;

}

Maybe the font you changed doesnt matches with the font of content on html pages. So, use this method to create attributed string with appropriate font:

// HTML -> NSAttributedString

-(NSAttributedString*) convertHTMLtoAttributedString: (NSString *) html {
NSError *error;
NSDictionary *options = @{NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType};
NSAttributedString *attrString = [[NSAttributedString alloc] initWithData:[html dataUsingEncoding:NSUTF8StringEncoding] options:options documentAttributes:nil error:&error];
if(!attrString) {
    NSLog(@"creating attributed string from HTML failed: %@", error.debugDescription);
}
return attrString;

}

// force font thrugh & css

- (NSAttributedString *)attributedStringFromHTML:(NSString *)html withFont:(UIFont *)font    {
return [self convertHTMLtoAttributedString:[NSString stringWithFormat:@"%@", font.fontName, font.pointSize, html]];

}

and in your tableView:heightForRowAtIndexPath: replace it with this:

case kContent:
        return [self textViewHeightForAttributedText:[self attributedStringFromHTML:myHTMLString withFont:contentFont] andFont:contentFont andWidth:self.tappableCell.width]; 
        break;