iOS 8.1中CGContextDrawPDFPage中的内存泄漏?

时间:2014-11-06 15:41:55

标签: ios objective-c memory-leaks ios8

在iOS 8.1下,我在使用CGContextDrawPDFPage将PDF页面渲染到图形上下文时出现内存泄漏。它并不是在模拟器中发生的,但每次我都会在iPad Air上获得数百个272字节的malloc内存泄漏。如果我注释掉CGContextDrawPDFPage,泄漏就会消失。

有没有其他人得到类似的行为?

CGDataProviderRef dataProvider = CGDataProviderCreateWithCFData((CFDataRef)data);
CGPDFDocumentRef pdf = CGPDFDocumentCreateWithProvider(dataProvider);


CGPDFPageRef page;

// Grab the PDF page
page = CGPDFDocumentGetPage(pdf, pageNo + 1);

UIGraphicsBeginImageContext(aRect.size);
CGContextRef context = UIGraphicsGetCurrentContext();

CGContextTranslateCTM(context, 0, aRect.size.height);
CGContextScaleCTM(context, 1, -1);

CGContextDrawPDFPage(context, page); // <-  LEAKING?!?!?

// Would create the new UIImage from the context
//image = UIGraphicsGetImageFromCurrentImageContext();

UIGraphicsEndImageContext();

CGPDFDocumentRelease(pdf);
CGDataProviderRelease(dataProvider);

这是一个堆栈跟踪(反向):

的malloc

38.58 MB 36.7%148743 std :: __ 1 :: list&gt; :: list(std :: __ 1 :: list&gt; const&amp;)

19.61 MB 18.6%75610 std :: __ 1 :: vector CG :: Path :: Subpath CG :: Allocator

19.61 MB 18.6%75610 void std :: __ 1 :: vector&gt; :: __ push_back_slow_path(CG :: Path :: Subpath&amp;&amp;)

19.61 MB 18.6%75610 CG :: Path :: Sequence :: move_to_point(CGPoint const&amp;,CGAffineTransform const *)

19.61 MB 18.6%75610 CGPathMoveToPoint

19.59 MB 18.6%75506 TTrueTypeQuadOutlineContext :: AddPoint(bool,int,int)

19.59 MB 18.6%75506 TTrueTypeFontHandler :: RenderGlyph(unsigned short,TTrueTypeQuadOutlineContext&amp;,unsigned int)const

19.59 MB 18.6%75506 TTrueTypeFontHandler :: GetOutlinePath(unsigned short,TGlyphOutlineBatch const&amp;)const

19.59 MB 18.6%75506 FPFontCopyGlyphPath

19.59 MB 18.6%75506 CGFontCreateGlyphPath

19.59 MB 18.6%75506 CGFontCreateGlyphBitmap

19.59 MB 18.6%75506 CGGlyphBuilder :: create_missing_bitmaps(CGGlyphIdentifier const *,unsigned long,CGGlyphBitmap const **)

19.59 MB 18.6%75506 render_glyphs

19.59 MB 18.6%75506 draw_glyph_bitmaps

19.59 MB 18.6%75506 ripc_DrawGlyphs

19.59 MB 18.6%75506 draw_glyphs

19.57 MB 18.6%75434 draw_glyphs

19.55 MB 18.6%75359 simple_draw

19.55 MB 18.6%75359 CGPDFTextLayoutDrawGlyphs

19.55 MB 18.6%75348 op_TJ

19.55 MB 18.6%75348 pdf_scanner_handle_xname

19.55 MB 18.6%75348 CGPDFScannerScan

19.55 MB 18.6%75348 CGPDFDrawingContextDrawPage

19.55 MB 18.6%75348 pdf_page_draw_in_context

19.55 MB 18.6%75348 CGContextDrawPDFPage

1 个答案:

答案 0 :(得分:0)

是的,您需要致电UIGraphicsEndImageContext()以匹配对UIGraphicsBeginImageContext()的每次通话。

根据UIKit framework reference

  

完成上下文修改后,必须调用   UIGraphicsEndImageContext函数用于清理位图绘图   环境并从顶部删除图形上下文   上下文堆栈。您不应该使用UIGraphicsPopContext功能   从堆栈中删除此类上下文。