I wanted to replace the content of a pdf page. I have done that by the following code,
-(void)modifyPdf:(NSString *)pdfPath atPage:(int)_page
{
NSURL* url = [NSURL fileURLWithPath:pdfPath];
CGPDFDocumentRef document = CGPDFDocumentCreateWithURL ((CFURLRef) url);
CGRect paperSize = CGPDFPageGetBoxRect(CGPDFDocumentGetPage (document, 1), kCGPDFMediaBox);
UIGraphicsBeginPDFContextToFile(pdfPath, paperSize, nil);
UIGraphicsBeginPDFPageWithInfo(paperSize, nil);
CGContextRef currentContext = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(currentContext, 0, paperSize.size.height);
CGContextScaleCTM(currentContext, 1.0, -1.0);
CGPDFPageRef page = CGPDFDocumentGetPage (document, _page);
CGContextDrawPDFPage (currentContext, page);
CGContextDrawImage(currentContext, CGRectMake(0, 0, 100, 100), [UIImage imageNamed:@"0_0_0.png"].CGImage);
UIGraphicsEndPDFContext();
CGPDFDocumentRelease(document);
document = nil;
}
(It adds an image in a specified page,i may need to draw a path or text).
The problem i faced here is, The modified file has only the changed page. To avoid it I have drawn all the pages. But the performance is so horrible for large file as expected. Is the any way to modify only a particular page?. Is there any other better way to do it?. Please help.
