创建多页PDF时出错 [英] Errors on creating a multipage PDF

问题描述

是否有人已在iPad应用中创建PDF文档？我看到UIKit中有新的功能来执行此操作，但我找不到任何代码示例。

Has anyone already created a PDF document in an iPad app? I see that there are new functions in the UIKit to do this, but I can't find any code example for it.

BOOL UIGraphicsBeginPDFContextToFile (
   NSString *path,
   CGRect bounds,
   NSDictionary *documentInfo
);

void UIGraphicsBeginPDFPage (
   void
);

我找到了一个可以在iPhone上运行的示例，但这给了我错误：

I found an example that is supposed to work on the iPhone, but this gives me errors:

Fri Apr 30 11:55:32 wks104.hs.local PDF[1963] <Error>: CGFont/Freetype: The function `create_subset' is currently unimplemented.
Fri Apr 30 11:55:32 wks104.hs.local PDF[1963] <Error>: invalid Type1 font: unable to stream font.
Fri Apr 30 11:55:32 wks104.hs.local PDF[1963] <Error>: FT_Load_Glyph failed: error 6.
Fri Apr 30 11:55:32 wks104.hs.local PDF[1963] <Error>: FT_Load_Glyph failed: error 6.
Fri Apr 30 11:55:32 wks104.hs.local PDF[1963] <Error>: FT_Load_Glyph failed: error 6.
Fri Apr 30 11:55:32 wks104.hs.local PDF[1963] <Error>: FT_Load_Glyph failed: error 6.

推荐答案

这是一个更好的解决方案，因为它使用正确的坐标转换来从上到下打印文本。

This is a better solution as it uses the correct coordinate transform to get the text to print from the top down.

#define LEFT_MARGIN 25
#define RIGHT_MARGIN 25
#define TOP_MARGIN 35
#define BOTTOM_MARGIN 50
#define BOTTOM_FOOTER_MARGIN 32
#define DOC_WIDTH 595
#define DOC_HEIGHT 842

- (void) createPDF:(NSString *)fileName withContent:(NSString *)content forSize:(int)fontSize andFont:(NSString *)font andColor:(UIColor *)color
{

    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *newFilePath = [[paths objectAtIndex:0] stringByAppendingPathComponent:fileName];

    CGRect a4Page = CGRectMake(0, 0, DOC_WIDTH, DOC_HEIGHT);

    NSDictionary *fileMetaData = [[NSDictionary alloc] init];

    if (!UIGraphicsBeginPDFContextToFile(newFilePath, a4Page, fileMetaData )) {
        NSLog(@"error creating PDF context");
        return;
    }

    CGContextRef context = UIGraphicsGetCurrentContext();
    UIGraphicsBeginPDFPage();

    CGContextSetTextDrawingMode (context, kCGTextFill);
    CGContextSelectFont (context, [font cStringUsingEncoding:NSUTF8StringEncoding], fontSize, kCGEncodingMacRoman);                                                 
    CGContextSetFillColorWithColor(context, [color CGColor]);

    CGMutablePathRef path = CGPathCreateMutable();

    CGRect bounds = CGRectMake(LEFT_MARGIN, 
                               TOP_MARGIN, 
                               DOC_WIDTH - RIGHT_MARGIN - LEFT_MARGIN, 
                               DOC_HEIGHT - TOP_MARGIN - BOTTOM_MARGIN
                               );

    CGPathAddRect(path, NULL, bounds);

    // Initialize an attributed string.
    CFMutableAttributedStringRef attrString =
    CFAttributedStringCreateMutable(kCFAllocatorDefault, 0);
    CFAttributedStringReplaceString (attrString, CFRangeMake(0, 0), (CFStringRef)content);

    // Create the framesetter with the attributed string.
    CTFramesetterRef framesetter =
    CTFramesetterCreateWithAttributedString(attrString);

    // Create the frame and draw it into the graphics context
    CTFrameRef frame = CTFramesetterCreateFrame(framesetter, CFRangeMake(0, 0), path, NULL);
    CFRange visibleRange = CTFrameGetVisibleStringRange(frame);

    if (visibleRange.length < [content length] ) {
        NSLog(@"WARNING: Not all displayed on a single page");
    }

    CFRelease(attrString);
    CFRelease(framesetter);

    if(frame) {
        CGContextSaveGState(context);
        CGContextTranslateCTM(context, 0, bounds.origin.y); 
        CGContextScaleCTM(context, 1, -1); 
        CGContextTranslateCTM(context, 0, -(bounds.origin.y + bounds.size.height)); 
        CTFrameDraw(frame, context);
        CGContextRestoreGState(context); 
        CFRelease(frame);       
    }

    UIGraphicsEndPDFContext();

    [fileMetaData release];
}

这篇关于创建多页PDF时出错的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！