NSColor objects have negative retainCount (-1)
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I was trying to track down a bug, and so got overly defensive, by adding
Asserts to my dealloc code. And when I attempted to verify that a
NSColor object was valid before releasing it, I keep getting complaints
about it having a retain count of -1. After hours of verifying every
retain/release of colors, I could only conclude that it was starting out
at -1.
So I created a simple test case:
int main (int argc, const char * argv[])
{
NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
{
NSColor* rColor = [NSColor redColor];
NSColor* bColor = [NSColor blueColor];
NSColor* gColor = [NSColor colorWithDeviceRed:0.0 green:1.0
blue:0.0 alpha:1.0];
int count = [rColor retainCount];
NSLog(@"Red's retain count = %d", count);
count = [bColor retainCount];
NSLog(@"Blue's retain count = %d", count);
count = [gColor retainCount];
NSLog(@"Green's retain count = %d", count);
}
[pool release];
return 0;
}
The red and blue colors have retain counts of -1 immediately after
calling the factory methods. But the green color does have a retain
count of 1, as expected.
Is there some reason the standard colors are being returned with a
negative retain count?
On a related note. Sometimes in the debugger, my color member variable
for a class, will not appear as a pointer. I don't know if memory is
getting corrupted due to the -1 issue, or if it's just a problem with
the debugger. But it's annoying.
TIA,
Brant -
> I was trying to track down a bug, and so got overly defensive, by
> adding Asserts to my dealloc code. And when I attempted to verify that
> a NSColor object was valid before releasing it, I keep getting
> complaints about it having a retain count of -1. After hours of
> verifying every retain/release of colors, I could only conclude that it
> was starting out at -1.
> ...
> NSColor* rColor = [NSColor redColor];
> NSColor* bColor = [NSColor blueColor];
> NSColor* gColor = [NSColor colorWithDeviceRed:0.0 green:1.0
> blue:0.0 alpha:1.0];
Actually that is a retain count of UINT_MAX, as retain counts are
unsigned. They are pegged at max.
Also, the reason why gColor has a retain count of 1 while the other two
are UINT_MAX is bacause the first two are cached colors (an
implementation optimization).
Ali
