iPhone 특정 PDFS는 검은 색 이미지로 렌더링됩니다
문제
아래 코드를 사용하여 PDF의 페이지를 그려 보려고합니다. 일부 PDF는 올바르게 렌더링되지만 다른 PDF는 단순히 완전히 검은 색 이미지로 표시되거나 부분적 부분이 렌더링되고 나머지는 검은 색을 가지고 있습니다. 무슨 일이 일어나고 있는지 비교할 때, OK를 보여주는 것은 항상 "일반"텍스트와 함께 일부 그래픽 (다이어그램 등)을 가지고있는 것 같습니다. 예를 들어 음악). 누구든지 이것에 대한 올바른 방향으로 나를 지적 할 수 있습니까? 나는 이것을 새로운 3.2 SDK에 구축합니다.
감사!
// PDF page drawing expects a Lower-Left coordinate system, so we flip the coordinate system
// before we start drawing.
CGContextTranslateCTM(context, 0.0, self.bounds.size.height);
CGContextScaleCTM(context, 1.0, -1.0);
// Grab the first PDF page
CGPDFPageRef page = CGPDFDocumentGetPage(myPDF, pageNo);
// We're about to modify the context CTM to draw the PDF page where we want it, so save the graphics state in case we want to do more drawing
CGContextSaveGState(context);
// CGPDFPageGetDrawingTransform provides an easy way to get the transform for a PDF page. It will scale down to fit, including any
// base rotations necessary to display the PDF page correctly.
CGAffineTransform pdfTransform = CGPDFPageGetDrawingTransform(page, kCGPDFCropBox, self.bounds, 0, true);
// And apply the transform.
CGContextConcatCTM(context, pdfTransform);
// Finally, we draw the page and restore the graphics state for further manipulations!
CGContextDrawPDFPage(context, page);
CGContextRestoreGState(context);
해결책
cgpdfdocumentref mygetpdfdocumentref (const char *filename) {cfstringref path; cfurlref url; cgpdfdocumentref 문서; PATH = CFStringCreateWithCString (NULL, FILENAME, KCFSTRINGENCODINGUTF8); url = cfurlcreatewithfilesystempath (null, path, kcfurlposixpathstyle, 0); cfrelease (경로); document = cgpdfdocumentCreateWitHurl (url); // 2 cfrelease (url); int count = cgpdfdocumentetGetnumberOfPages (document); // 3 if (count == 0) {printf ( "`%s '가 하나 이상의 페이지가 필요합니다!", filename); 리턴 널; } 반환 문서; }
void MyDisplayPDFPage (CGContextRef myContext,size_t pageNumber,const char *filename) {
CGPDFDocumentRef document;
CGPDFPageRef page;
document = MyGetPDFDocumentRef (filename);// 1
page = CGPDFDocumentGetPage (document, pageNumber);// 2
CGContextDrawPDFPage (myContext, page);// 3
CGContextTranslateCTM(myContext, 0, 20);
CGContextScaleCTM(myContext, 1.0, -1.0);
CGPDFDocumentRelease (document);// 4
}
#import "DashBoard.h"
#import <QuartzCore/QuartzCore.h>
@interface UIImage (WBImage)
// rotate UIImage to any angle
-(UIImage*)rotate:(UIImageOrientation)orient;
@end
@implementation UIImage (WBImage)
static inline CGFloat degreesToRadians(CGFloat degrees)
{
return M_PI * (degrees / 180.0);
}
static inline CGSize swapWidthAndHeight(CGSize size)
{
CGFloat swap = size.width;
size.width = size.height;
size.height = swap;
return size;
}
-(UIImage*)rotate:(UIImageOrientation)orient
{
CGRect bnds = CGRectZero;
UIImage* copy = nil;
CGContextRef ctxt = nil;
CGRect rect = CGRectZero;
CGAffineTransform tran = CGAffineTransformIdentity;
bnds.size = self.size;
rect.size = self.size;
switch (orient)
{
case UIImageOrientationUp:
return self;
case UIImageOrientationUpMirrored:
tran = CGAffineTransformMakeTranslation(rect.size.width, 0.0);
tran = CGAffineTransformScale(tran, -1.0, 1.0);
break;
case UIImageOrientationDown:
tran = CGAffineTransformMakeTranslation(rect.size.width,
rect.size.height);
tran = CGAffineTransformRotate(tran, degreesToRadians(180.0));
break;
case UIImageOrientationDownMirrored:
tran = CGAffineTransformMakeTranslation(0.0, rect.size.height);
tran = CGAffineTransformScale(tran, 1.0, -1.0);
break;
case UIImageOrientationLeft:
bnds.size = swapWidthAndHeight(bnds.size);
tran = CGAffineTransformMakeTranslation(0.0, rect.size.width);
tran = CGAffineTransformRotate(tran, degreesToRadians(-90.0));
break;
case UIImageOrientationLeftMirrored:
bnds.size = swapWidthAndHeight(bnds.size);
tran = CGAffineTransformMakeTranslation(rect.size.height,
rect.size.width);
tran = CGAffineTransformScale(tran, -1.0, 1.0);
tran = CGAffineTransformRotate(tran, degreesToRadians(-90.0));
break;
case UIImageOrientationRight:
bnds.size = swapWidthAndHeight(bnds.size);
tran = CGAffineTransformMakeTranslation(rect.size.height, 0.0);
tran = CGAffineTransformRotate(tran, degreesToRadians(90.0));
break;
case UIImageOrientationRightMirrored:
bnds.size = swapWidthAndHeight(bnds.size);
tran = CGAffineTransformMakeScale(-1.0, 1.0);
tran = CGAffineTransformRotate(tran, degreesToRadians(90.0));
break;
default:
// orientation value supplied is invalid
assert(false);
return nil;
}
UIGraphicsBeginImageContext(bnds.size);
ctxt = UIGraphicsGetCurrentContext();
switch (orient)
{
case UIImageOrientationLeft:
case UIImageOrientationLeftMirrored:
case UIImageOrientationRight:
case UIImageOrientationRightMirrored:
CGContextScaleCTM(ctxt, -1.0, 1.0);
CGContextTranslateCTM(ctxt, -rect.size.height, 0.0);
break;
default:
CGContextScaleCTM(ctxt, 1.0, -1.0);
CGContextTranslateCTM(ctxt, 0.0, -rect.size.height);
break;
}
CGContextConcatCTM(ctxt, tran);
CGContextDrawImage(ctxt, rect, self.CGImage);
copy = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return copy;
}
@end
@implementation DashBoard
// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad {
[super viewDidLoad];
filePath=[[NSString alloc] initWithString:[[NSBundle mainBundle] pathForResource:@"roadie" ofType:@"pdf"]];
// an IBOutlet UIScrollView
[scrMain setContentSize:CGSizeMake(720, 720)];
// an IBOutlet UIImageView
[imgV setFrame:CGRectMake(0, 0, 720, 720)];
UIGraphicsBeginImageContext(CGSizeMake(720, 720));
// initial page is an size_t variable
initialPage=1;
MyDisplayPDFPage(UIGraphicsGetCurrentContext(), initialPage, [filePath UTF8String],myTable,mainString);
imgV.image=UIGraphicsGetImageFromCurrentImageContext();
imgV.image=[imgV.image rotate:UIImageOrientationDownMirrored];
}
코드 위에 복사하여 붙여 넣기 만하면됩니다. 그것은 당신을 위해 효과가있을 것입니다.
다른 팁
문제는 배경색이었습니다. 구체적으로, 내가 문제가있는 PDF는 흰색 배경이 없었습니다. 흰색 사각형으로보기를 채우면 내 문제가 해결되었습니다.