PDF Document Creation, Viewing

【PDF Document Creation, Viewing, and Transforming】

　　Quartz provides the data type CGPDFDocumentRef to represent a PDF document. You create a CGPDFDocument object using either the function CGPDFDocumentCreateWithProvider or the function CGPDFDocumentCreateWithURL. After you create a CGPDFDocument object, you can draw it to a graphics context.

　　Following code shows how to create a CGPDFDocument object and obtain the number of pages in the document. by

CGPDFDocumentGetNumberOfPages function. A detailed explanation for each numbered line of code appears following the listing.

 1 CGPDFDocumentRef MyGetPDFDocumentRef (const char *filename)

 2 {

 3     CFStringRef path;

 4     CFURLRef url;

 5     CGPDFDocumentRef document;

 6     size_t count;

 7  

 8     path = CFStringCreateWithCString (NULL, filename,

 9                          kCFStringEncodingUTF8);

10     url = CFURLCreateWithFileSystemPath (NULL, path, // 1

11                         kCFURLPOSIXPathStyle, 0);

12     CFRelease (path);

13     document = CGPDFDocumentCreateWithURL (url);// 2

14     CFRelease(url);

15     count = CGPDFDocumentGetNumberOfPages (document);// 3

16     if (count == 0) {

17         printf("`%s' needs at least one page!", filename);

18         return NULL;

19     }

20     return document;

21 }

View Code

　　Drawing a PDF page:

 1 void MyDisplayPDFPage (CGContextRef myContext,

 2                     size_t pageNumber,

 3                     const char *filename)

 4 {

 5     CGPDFDocumentRef document;

 6     CGPDFPageRef page;

 7  

 8     document = MyGetPDFDocumentRef (filename);// 1

 9     page = CGPDFDocumentGetPage (document, pageNumber);// 2

10     CGContextDrawPDFPage (myContext, page);// 3

11     CGPDFDocumentRelease (document);// 4

12 }

View Code