iOS: How to set font when drawing text in pdf gene

问题:

I'am generating a pdf in ios app, using drawpdf function,while calling the drawtext function in the nsobject class it draws the text clearly according to the frame and string which I specified.

My code is

+(void)drawText:(NSString*)textToDraw inFrame:(CGRect)frameRect
{

    CFStringRef stringRef = (__bridge CFStringRef)textToDraw;
// Prepare the text using a Core Text Framesetter
    CFAttributedStringRef currentText = CFAttributedStringCreate(NULL, stringRef, NULL);
    CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString(currentText);


    CGMutablePathRef framePath = CGPathCreateMutable();
    CGPathAddRect(framePath, NULL, frameRect);

// Get the frame that will do the rendering.
    CFRange currentRange = CFRangeMake(0, 0);
    CTFrameRef frameRef = CTFramesetterCreateFrame(framesetter, currentRange, framePath, NULL);
    CGPathRelease(framePath);

// Get the graphics context.
    CGContextRef    currentContext = UIGraphicsGetCurrentContext();

// Put the text matrix into a known state. This ensures
// that no old scaling factors are left in place.
    CGContextSetTextMatrix(currentContext, CGAffineTransformIdentity);


// Core Text draws from the bottom-left corner up, so flip
// the current transform prior to drawing.
    CGContextTranslateCTM(currentContext, 0, frameRect.origin.y*2);
    CGContextScaleCTM(currentContext, 1.0, -1.0);
// Draw the frame.
    CTFrameDraw(frameRef, currentContext);

    CGContextScaleCTM(currentContext, 1.0, -1.0);
    CGContextTranslateCTM(currentContext, 0, (-1)*frameRect.origin.y*2);


    CFRelease(frameRef);
    CFRelease(stringRef);
    CFRelease(framesetter);
}

But I need to set the text fontsize bigger and bolder.

I used

CGContextSelectFont(currentContext, "Helvetica", 20, kCGEncodingMacRoman);

and

CGContextSetFontSize ( currentContext, 20);

with reference to the answer provided by mr.texian in the above function, but no changes

I am showing the generated pdf in uiwebview.

I got this code from net. I didn't know where to edit the code for font setting. Any help will be appreciated.

回答1:

Please try CoreText, a very useful foundation class. Following is the sample code:

CTFontRef font = CTFontCreateWithName((CFStringRef)@"Arial", 16.0f, nil);
CFAttributedStringSetAttribute(textString,CFRangeMake(0, strLength-1), kCTFontAttributeName, font);

Add this to the CFAttributtedStringRef pointer.

This should work.

回答2:

I think these are what you are looking for

void CGContextSelectFont (
    CGContextRef c,
    const char *name,
    CGFloat size,
    CGTextEncoding textEncoding
);

and

void CGContextSetFontSize (
   CGContextRef c,
   CGFloat size
);

Something like...

CGContextSelectFont(currentContext, "Helvetica", 20, kCGEncodingMacRoman);

or

CGContextSetFontSize ( currentContext, 20);

Hope that helps, here is more... Quartz 2D Programming Guide - Text

回答3:

Create a CTFont using CTFontCreateWithNameAndOptions (check : CTFont Reference)

Create a mutable attributed string (CFMutableAttributedString Reference) You can edit this mutable string and make any changes you want. In your case, set it's font.

Create your CTFrameSetter with this string and the font should appear.

If you want to be thorough and have enough time, read the String programming Guide

If you want a quick code sample for using CFMutableAttributedString, search CFMutableAttributedString on stackoverflow and most answers will give you an idea of how to use this. For e.g. this question

回答4:

You can try "libHaru" for generating pdf in iPhone project.

https://github.com/akisute/iPhonePDF

Hope it Helps !!!

回答5:

What about CGContextSetFont?

NSString *fontName = @"Helvetica";
CGFontRef fontRef = CGFontCreateWithFontName((__bridge CFStringRef)fontName);
CGContextSetFont(context, fontRef);
CGContextSetFontSize(context, 20);

Don't forget to release it:

CGFontRelease(fontRef);

回答6:

After a lot search, fnd that itsdamslife's answer is correct, but it didn't support for my code.

But, I solved it cheaply. ie, called multiple times the drawText: function to get bold font.

for(int i=0;i<5;i++)
{
 [self drawtext];
}