"Potential leak of an object" when using Core Graphics

Question

My app is drawing a shadow using the following code:

-(void)drawShadow:(CGContextRef)context rect:(CGRect)rect{

    CGContextSaveGState(context);

    //Set color of current context
    [[UIColor blackColor] set];

    //Set shadow and color of shadow
    CGContextSetShadowWithColor(context, CGSizeMake(0, 2), 3, [[UIColor colorWithWhite:0 alpha:0.5] CGColor]);

    CGContextFillEllipseInRect(context, rect);

    CGContextClipToMask(context, rect, CGBitmapContextCreateImage(context));

    CGContextRestoreGState(context); // Warning shows in this line

}

When I run Product > Analyze, it marks the last instruction of this block with the message: "Potential leak of an object". When I remove that line, it shows the same message but in the closing bracket.

Any idea of what I'm doing wrong?

Thanks

score 2 · Accepted Answer · edited May 23 '17 at 11:59

2

I think it's the CGBitmapContextCreateImage that is leaking.

Try assigning it to a local variable and then calling CGImageRelease with it once you've clipped to mask.

Another iPhone - CGBitmapContextCreateImage Leak

edited May 23 '17 at 11:59

Community

1
1

answered Jan 15 '16 at 23:17

chedabob

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score 0 · Answer 2 · answered Jan 15 '16 at 23:27

chedabob's answer worked! Here's the final code:

-(void)drawShadow:(CGContextRef)context rect:(CGRect)rect{
    CGContextSaveGState(context);
    //Set color of current context
    [[UIColor blackColor] set];
    //Set shadow and color of shadow
    CGContextSetShadowWithColor(context, CGSizeMake(0, 2), 3, [[UIColor colorWithWhite:0 alpha:0.5] CGColor]);
    CGContextFillEllipseInRect(context, rect);

    CGImageRef bitmap = CGBitmapContextCreateImage(context);
    CGContextClipToMask(context, rect, bitmap);
    CGContextRestoreGState(context);

    CGImageRelease(bitmap);
}

"Potential leak of an object" when using Core Graphics

2 Answers2