Problems with placing NSAttributedString in a PDF - ios

Question

I'm building a PDF document dynamically in an iOS app. I am trying to convert an HTML formatted string to an NSAttributedString, then position it on my PDF document page.
If I treat the string as a plain NSString I can set it's frame and position it anywhere on the page (html tags included in the string).
If I create an NSAttributedString using initWithString I can also place the resulting attributed string anywhere on the page.
If I convert the string to an NSAttributedString using
NSAttributedString initWithData:options:documentAttributes:error:
the conversion work perfectly, and the tags are converted to attributes. But when I try to position the string's frame on the page the text is clipped as I move the frame down and right from 0,0. I can move the frame down 20 points before the text is clipped off the top, line by line. I can move the frame right until the origin is larger than the width, when all the text disappears from the page.
Code:
#pragma mark - === PDF BUILD Methods === -
- (void)buildPDF {
self.pdfPageSize = CGSizeMake(850.0, 1100.0);
UIFont *titleFont = [UIFont fontWithName:#"Dispatch-Bold" size:24.0];
UIFont *bodyFont = [UIFont systemFontOfSize:18.0];
// Open a new PDF dcument
[self setupPDFDocumentNamed:#"testPDF" Width:self.pdfPageSize.width Height:self.pdfPageSize.height];
//cover page
[self beginPDFPage];
NSString *title = [NSString stringWithFormat:#"How to Tie a %#", self.knot.knotName];
[self addText:title withFrame:CGRectMake(0, 10, 850, 30) font:titleFont alignment:NSTextAlignmentCenter];
[self addLineWithFrame:CGRectMake(10, 40, 830, 2) withColor:[CSCColors favoritesColor]];
NSString *imageName = [NSString stringWithFormat:#"%#_0", self.knot.knotID];
[self addImage:[UIImage imageNamed:imageName] atPoint:CGPointMake(50, 50)];
// addText method works, but addHTML method does not
//[self addText:self.knot.knotDescription withFrame:CGRectMake(400, 50, 300, 500) font:bodyFont alignment:NSTextAlignmentLeft];
[self addHTMLText:self.knot.knotDescription withFrame:CGRectMake(400, 50, 300, 500) font:bodyFont alignment:NSTextAlignmentLeft];
//close out the PDF
[self finishPDF];
}
-(void)setupPDFDocumentNamed:(NSString*)name Width:(float)width Height:(float)height {
self.pdfPageSize = CGSizeMake(width, height);
NSString *newPDFName = [NSString stringWithFormat:#"%#.pdf", name];
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *pdfPath = [documentsDirectory stringByAppendingPathComponent:newPDFName];
UIGraphicsBeginPDFContextToFile(pdfPath, CGRectZero, nil);
}
- (void)beginPDFPage {
UIGraphicsBeginPDFPageWithInfo(CGRectMake(0, 0, self.pdfPageSize.width, self.pdfPageSize.height), nil);
}
- (void)finishPDF {
UIGraphicsEndPDFContext();
}
- (void)addText:(NSString*)text withFrame:(CGRect)frame font:(UIFont*)font alignment:(NSTextAlignment)alignment{
// Set up character and paragraph attributes
UIColor * cscBlueColor = [UIColor colorWithRed:0.0 green:0.53 blue:0.8 alpha:1.0];
NSMutableParagraphStyle *paraStyle = [[NSMutableParagraphStyle alloc] init];
paraStyle.lineBreakMode = NSLineBreakByWordWrapping;
paraStyle.alignment = alignment;
//Calculate frame
NSDictionary *attr = #{NSFontAttributeName:font};
CGRect textRect = [text boundingRectWithSize:frame.size options:NSStringDrawingUsesLineFragmentOrigin attributes:attr context:nil];
CGSize stringSize = textRect.size;
float textWidth = frame.size.width;
if (textWidth < stringSize.width)
textWidth = stringSize.width;
if (textWidth > _pdfPageSize.width)
textWidth = _pdfPageSize.width - frame.origin.x;
CGRect renderingRect = CGRectMake(frame.origin.x, frame.origin.y, textWidth, stringSize.height);
NSDictionary *renderingAttr = #{NSParagraphStyleAttributeName:paraStyle, NSFontAttributeName:font, NSForegroundColorAttributeName:cscBlueColor};
[text drawInRect:renderingRect withAttributes:renderingAttr];
}
- (void)addHTMLText:(NSString*)text withFrame:(CGRect)frame font:(UIFont *)font alignment:(NSTextAlignment)alignment{
NSMutableAttributedString *myString = [[NSMutableAttributedString alloc] initWithData:[text dataUsingEncoding:NSUTF8StringEncoding]
options:#{NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType,
NSCharacterEncodingDocumentAttribute: [NSNumber numberWithInt:NSUTF8StringEncoding]}
documentAttributes:nil
error:nil];
NSRange myRange;
myRange.location = 0;
myRange.length = myString.length;
// Set up character and paragraph attributes
UIColor * cscBlueColor = [UIColor colorWithRed:0.0 green:0.53 blue:0.8 alpha:1.0];
NSMutableParagraphStyle *paraStyle = [[NSMutableParagraphStyle alloc] init];
paraStyle.lineBreakMode = NSLineBreakByWordWrapping;
paraStyle.paragraphSpacing = 10.0f;
paraStyle.alignment = alignment;
NSDictionary *renderingAttr = #{NSParagraphStyleAttributeName:paraStyle, NSFontAttributeName:font, NSForegroundColorAttributeName:cscBlueColor};
[myString addAttributes:renderingAttr range:myRange];
//Calculate frame
NSStringDrawingContext *sdctx = [[NSStringDrawingContext alloc] init];
CGRect textRect = [myString boundingRectWithSize:CGSizeMake(frame.size.width, CGFLOAT_MAX) options:NSStringDrawingUsesLineFragmentOrigin context:sdctx];
CGSize stringSize = textRect.size;
float textWidth = frame.size.width;
if (textWidth < stringSize.width)
textWidth = stringSize.width;
if (textWidth > _pdfPageSize.width)
textWidth = _pdfPageSize.width - frame.origin.x;
CGRect renderingRect = CGRectMake(frame.origin.x, frame.origin.y, textWidth, stringSize.height);
// fill rect so we can visualize the frame
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetFillColorWithColor(context, [UIColor lightGrayColor].CGColor);
CGContextFillRect(context, renderingRect);
//[myString drawInRect:renderingRect];
[myString drawWithRect:renderingRect options:NSStringDrawingUsesLineFragmentOrigin context:sdctx];
}
- (void)addImage:(UIImage*)image atPoint:(CGPoint)point {
CGRect imageFrame = CGRectMake(point.x, point.y, image.size.width, image.size.height);
[image drawInRect:imageFrame];
}
- (void)addLineWithFrame:(CGRect)frame withColor:(UIColor*)color {
CGContextRef currentContext = UIGraphicsGetCurrentContext();
CGContextSetStrokeColorWithColor(currentContext, color.CGColor);
// this is the thickness of the line
CGContextSetLineWidth(currentContext, 2);
CGPoint startPoint = frame.origin;
CGPoint endPoint = CGPointMake(frame.origin.x + frame.size.width, frame.origin.y);
CGContextBeginPath(currentContext);
CGContextMoveToPoint(currentContext, startPoint.x, startPoint.y);
CGContextAddLineToPoint(currentContext, endPoint.x, endPoint.y);
CGContextClosePath(currentContext);
CGContextDrawPath(currentContext, kCGPathFillStroke);
}
Any ideas?
Screen caps:
For the 1st two screen caps, I used
NSAttributedString initWithData:options:documentAttributes:error:
to generate the attributed string
In the first, frame is set to {400, 50, 300, 500} and text is clipped completely.
In the second the frame is {400, 50, 401, 500}, the text appears, but the 1st two lines of text is clipped at the top. If I move the frame up to 20, all lines are visible.
In the final screen shot I just used initWithString to get the attributed string, and everything works as it should, except that the HTML is not converted to attributes.
I've also cleaned up the HTML string to make sure tht the tags and class calls were not introducing some wierd attributes. The cleaned up string has the same results:
<html><body><p>Landlubbers need not apply. The Sheet Bend is an essential knot to know and one of the first knots taught to new sailors. It is very fast to tie and is useful when joining two ropes of different diameters.</p><p>Also known as Becket bend (when made fast to an eye instead of a loop), the Sheet Bend is often considered one of the most essential knots and is related in structure to the bowline. If the two free ends are not on the same side of the knot, the result is a left-handed sheet bend of significantly reduced strength.</p></body></html>
Thanks