iPhone CGPDFDocumentRef巨大的内存泄漏

Question

I've been doing research because my pdf viewer app keeps crashing around page 4/5 because of a memory leak that happens every time you turn a page.

It turns out that apple has a bug.

see here: https://devforums.apple.com/message/9077#9077

From what I understand you have to release & retain the pdf document every time you change page.

I can't get it to work (this code is in a subclass of UIView):

- (void) drawInContext: (CGContextRef) ctx {
CGPDFDocumentRelease(__pdfDoc);
CGContextSetRGBFillColor( ctx, 1.0, 1.0, 1.0, 1.0 );
CGContextFillRect( ctx, CGContextGetClipBoundingBox( ctx ));
CGContextTranslateCTM( ctx, 0.0, self.bounds.size.height );
CGContextScaleCTM( ctx, 1.0, -1.0 );
CGContextConcatCTM(ctx, CGPDFPageGetDrawingTransform(pdfPage, kCGPDFCropBox, self.bounds, 0, true));
CGContextDrawPDFPage( ctx, pdfPage );NSLog(@"DONE!");
CGPDFDocumentRetain(__pdfDoc);}
@end

my pdf is opened here in a viewController:

- (CGPDFPageRef) pdfPage: (NSInteger) index {
if( ! __pdfDoc ) {
__pdfDoc = CGPDFDocumentCreateWithURL((CFURLRef)[NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:@"mybook" ofType:@"pdf"]]);}
if( __pdfDoc ) {
size_t pdfPageCount = CGPDFDocumentGetNumberOfPages( __pdfDoc );
index++;
if( index < 1 )
index = 1;
if( index > pdfPageCount )
index = pdfPageCount;
CGPDFPageRef page = CGPDFDocumentGetPage( __pdfDoc, index );
return page;}
return nil;}

I can't find anything on google and I've been reading the documentation all day.

Answer 1

Yeah. Bug. You will have to open/close the complete document when drawing a page. Sucks.

(I think this is fixed in 3.2.x)