ios – 如何使用Annots创建PDF？

我试图在具有注释的代码中生成PDF,例如小部件和链接.我可以生成PDF并修改文档信息和页面的MediaBox,但我无法弄清楚如何添加到Annotations.我尝试将其添加到页面字典中,但由于某种原因,PDF不接受它.

有谁知道如何为新创建的PDF添加注释？下面是我要生成PDF的代码和我试图添加到它的测试Annotation字典：

-(void) createPDFFile: (CGPDFPageRef) pageRef{

CGContextRef pdfContext;

CFStringRef path;

CFURLRef url;


CFMutableDictionaryRef myDictionary = NULL;

 NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask,YES); 
 NSString *documentsDirectory = [paths objectATindex:0]; // Get documents folder
 const char *filepath = [[documentsDirectory StringByAppendingString:@"/fileTest.pdf"] UTF8String];

path = CFStringCreateWithCString (NULL,filepath,kcfStringEncodingUTF8);

url = CFURLCreateWithFileSystemPath (NULL,path,kcfURLPOSIXPathStyle,0);

CFRelease (path);

myDictionary = CFDictionaryCreateMutable(NULL,&kcfTypeDictionaryKeyCallBACks,&kcfTypeDictionaryValueCallBACks); 

CFDictionarySETVALue(myDictionary,kCGPDFContexttitle,CFSTR("My PDF File"));

CFDictionarySETVALue(myDictionary,kCGPDFContextCreator,CFSTR("My Name"));

CGRect pageRect = self.bounds;
pdfContext = CGPDFContextCreateWithURL (url,&pageRect,myDictionary); // 5

CFRelease(myDictionary);

CFRelease(url);

CGRect mediaBox;
mediaBox = CGRectMake (0,pageRect.size.width,100);
CFStringRef myKeys[1];

CFTypeRef myValues[1];

myKeys[0] = CFSTR("MediaBox");

myValues[0] = (CFTypeRef) CFDataCreate(NULL,(const UInt8 *)&mediaBox,sizeof (CGRect));

CFDictionaryRef pageDictionary = CFDictionaryCreate(NULL,(const void **) myKeys,(const void **) myValues,1,& kcfTypeDictionaryValueCallBACks);
CFMutableDictionaryRef pageDictionarymutable = CFDictionaryCreateMutableCopy(NULL,pageDictionary);

CFMutableDictionaryRef  MetaDataDictionary = CFDictionaryCreateMutable(NULL,&kcfTypeDictionaryValueCallBACks); 

CFDictionarySETVALue(MetaDataDictionary,CFSTR("DA"),CFSTR("/Helvetica 10 Tf 0 g"));
CFDictionarySETVALue(MetaDataDictionary,CFSTR("F"),CFSTR("4"));
CFDictionarySETVALue(MetaDataDictionary,CFSTR("FT"),CFSTR("Tx"));
CFDictionarySETVALue(MetaDataDictionary,CFSTR("Subtype"),CFSTR("Widget"));
CFDictionarySETVALue(MetaDataDictionary,CFSTR("T"),CFSTR("undefined"));
CFDictionarySETVALue(MetaDataDictionary,CFSTR("Type"),CFSTR("Annot"));
CFDictionarySETVALue(MetaDataDictionary,CFSTR("V"),CFSTR(""));
CFMutableArrayRef array = CFArrayCreateMutable(kcfAllocatorDefault,&kcfTypeArrayCallBACks);
CFArrayInsertValueATindex(array,MetaDataDictionary);

CFDictionarySETVALue(pageDictionarymutable,CFSTR("Annots"),array);


CGPDFContextBeginPage (pdfContext,pageDictionarymutablE);


CGPDFContextEndPage (pdfContext);

CGContextRelease (pdfContext);

CFRelease(pageDictionary);}

打印出CFMutableDictionary pageDictionarymutable表示应该将Annots字典添加到PDF以及MediaBox：

(gdb) po pageDictionarymutable
{
    Annots =     (
                {
            DA = "/Helvetica 10 Tf 0 g";
            F = 4;
            FT = Tx;
            Subtype = Widget;
            T = undefined;
            Type = Annot;
            V = "";
        }
    );
    MediaBox = <00000000 00000000 00008044 0000c842>;
}

@H_70_5@media Box需要,但Annots没有.请帮助任何人！