Re: Accessing a managedObject property from within an accessor of another property
[A]nd then it occurred to me that a computer is a stupid machine with the ability to do incredibly smart things, while computer programmers are smart people with the ability to do incredibly stupid things. They are, in short, a perfect match. ~Bill Bryson On Feb 22, 2011, at 11:42 PM, Quincey Morris wrote: That's a lot of information you posted. :) Unfortunately, *based on the posted information* there's nothing obviously wrong except that you've shot yourself in the foot using the debugger. Let's look, for example, at what one of the backtraces is telling you. You triggered this by typing 'po self' in the debugger: On Feb 22, 2011, at 19:34, Brad Stone wrote: Breakpoint 28, -[SRMainWindowController toggleLock:] (self=0x2000df5e0, _cmd=0x1000a9239, sender=0x2000df5e0) at SRMainWindowController.m:2897 2897 [note setIsEncrypted:[NSNumber numberWithBool:YES]]; The program being debugged stopped while in a function called from GDB. When the function (_NSPrintForDebugger) is done executing, GDB will silently stop (instead of continuing to evaluate the expression containing the function call). A function called from the debugger as a result of 'po self' failed. What function? It's not clear yet, but it *is* clear what failed -- that function directly or indirectly called 'toggleLock:' *again* -- the method you were in when you started all this debugging activity. Why did it stop? It hit the breakpoint that you put in that code. This backtrace is enlightening, unlike the earlier ones, because it shows what the debugger was trying to do: Here's a backtrace right after po #3 before I'm out of setIsEncrypted backtrace #0 -[SRMainWindowController toggleLock:] (self=0x2000df5e0, _cmd=0x1000a9239, sender=0x2000df5e0) at SRMainWindowController.m:2897 #1 0x00010002dae9 in -[SRMainWindowController getEncryptionKey] (self=0x2000df5e0, _cmd=0x1000a7210) at SRMainWindowController.m:2948 #2 0x000198d2 in -[Note category] (self=0x20027bda0, _cmd=0x7fff85450184) at Note.m:257 #3 0x000189c8 in -[Note description] (self=0x20027bda0, _cmd=0x7fff83c821e8) at Note.m:56 The debugger was trying to execute [note description], which is what it does to get a description to display as a result of 'po note'. Normally, the standard 'description' in NSObject is called, which just prints the address of the object and its class. You, apparently have overridden 'description' in the Note class, and it apparently invokes 'category', which invokes '-[SRMainWindowController getEncryptionKey]', which invokes 'toggleLock:', which is why it hits the breakpoint again. Note that (apparently) if isEncrypted is NO, then 'getEncryptionKey' isn't invoked, and so 'toggleLock' isn't invoked either. That's why setting isFlagged instead didn't crap out in the debugger. Other than indicating an inappropriate design of your 'description' override, there's absolutely no indication of anything wrong here at all. It looks like you've been chasing a chimera. :) Obviously I may be overlooking something, but step 1 is to fix your 'description' method so that it doesn't cause Core Data fetches. #4 0x7fff868a386b in _NSPrintForDebugger () #5 function called from gdb #6 -[Note setIsEncrypted:] (self=0x20027bda0, _cmd=0x1000a6eb8, value=0x7fff70886280) at Note.m:206 #7 0x00010002d5c9 in -[SRMainWindowController toggleLock:] (self=0x2000df5e0, _cmd=0x1000a9239, sender=0x2000867e0) at SRMainWindowController.m:2897 #8 0x7fff83b2afbf in -[NSToolbarButton sendAction:to:] () #9 0x7fff8379c135 in -[NSToolbarItemViewer mouseDown:] () #10 0x7fff8368934f in -[NSWindow sendEvent:] () #11 0x7fff835bea86 in -[NSApplication sendEvent:] () #12 0x7fff835554da in -[NSApplication run] () #13 0x7fff8354e1a8 in NSApplicationMain () #14 0x00016b60 in main (argc=1, argv=0x7fff5fbff628) at main.m:13 ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
Accessing a managedObject property from within an accessor of another property
I've been trying for days to determine why I get EXC_BAD_ACCESS when I try to
access a managedObject property from within an accessor of another property?
this code in main.m
[[self note] setValue:@HELLO WORLD forKey:@category];
NSNumber *tmpVal = [NSNumber numberWithBool:![[[self note]
valueForKey:@isEncrypted] boolValue]]; // if I type po [self note] I see the
note description
[[self note] setValue:tmpVal forKey:@isEncrypted]; // if I type po [self
note] after this I get EXEC_BAD_ACCESS
The if statement in the accessor is causing the problem:
- (NSString *)category {
NSString * tmpValue;
[self willAccessValueForKey:@category];
tmpValue = [self primitiveCategory];
[self didAccessValueForKey:@category];
if ([[self valueForKey:@isEncrypted] boolValue]) { // THIS IS CAUSING
THE PROBLEM
// code to decrypt tmpValue
}
return tmpValue;
}
When I replace: if ([[self valueForKey:@isEncrypted] boolValue]) with if (1
== 2 ) or if (1 == 1 ) it works
FYI: in my .h file @property (nonatomic, retain) NSNumber * isEncrypted; and
@dynamic isEncrypted; in .m___
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Fwd: Accessing a managedObject property from within an accessor of another property
FYI - my managedObject is defined as such:
@interface Note : NSManagedObject
{
}
@property (nonatomic, retain) NSNumber * uid;
@property (nonatomic, retain) NSString * category;
@property (nonatomic, retain) NSNumber * isEncrypted;
@interface Note (CoreDataGeneratedPrimitiveAccessors)
- (NSString *)primitiveCategory;
- (void)setPrimitiveCategory:(NSString *)value;
@end
@implementation Note
@dynamic uid;
@dynamic category;
@dynamic isEncrypted;
- (NSString *)category
{
NSString * tmpValue;
[self willAccessValueForKey:@category];
tmpValue = [self primitiveCategory];
[self didAccessValueForKey:@category];
if ([[self valueForKey:@isEncrypted] boolValue]) {
//code to decrypt tmpValue
}
return tmpValue;
}
- (void)setCategory:(NSString *)value
{
if ([[self valueForKey:@isEncrypted] boolValue]) {
// code to encrypt tmpValue
}
[self willChangeValueForKey:@category];
[self setPrimitiveCategory:value];
[self didChangeValueForKey:@category];
}
- (BOOL)validateCategory:(id *)valueRef error:(NSError **)outError
{
// Insert custom validation logic here.
return YES;
}
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Re: Accessing a managedObject property from within an accessor of another property
On 22.02.2011, at 16:13, Brad Stone wrote:
FYI - my managedObject is defined as such:
@interface Note : NSManagedObject
{
}
That's probably not your problem, but just to eliminate it as a cause: You
should prefix your class names. Apple has been known to create internal private
classes with un-prefixed names (like Account). And once one class with a
particular name has been loaded, requests to load any other class of the same
name will be ignored. Anyone trying to create an instance of such a class will
get the first class that was loaded, which is probably something completely
different.
So I recommend choosing your own three-character prefix (BST?), just in case
there's some private Apple class named Note.
Cheers,
-- Uli Kusterer
The Witnesses of TeachText are everywhere...
http://www.zathras.de
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Re: Accessing a managedObject property from within an accessor of another property
Yes, all my other classes are prefixed with SR since this one. I haven't
gotten back to fixing this.
On Feb 22, 2011, at 10:22 AM, Uli Kusterer wrote:
On 22.02.2011, at 16:13, Brad Stone wrote:
FYI - my managedObject is defined as such:
@interface Note : NSManagedObject
{
}
That's probably not your problem, but just to eliminate it as a cause: You
should prefix your class names. Apple has been known to create internal
private classes with un-prefixed names (like Account). And once one class
with a particular name has been loaded, requests to load any other class of
the same name will be ignored. Anyone trying to create an instance of such a
class will get the first class that was loaded, which is probably something
completely different.
So I recommend choosing your own three-character prefix (BST?), just in case
there's some private Apple class named Note.
Cheers,
-- Uli Kusterer
The Witnesses of TeachText are everywhere...
http://www.zathras.de
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Re: Accessing a managedObject property from within an accessor of another property
On Feb 22, 2011, at 06:19, Brad Stone wrote:
I've been trying for days to determine why I get EXC_BAD_ACCESS when I try to
access a managedObject property from within an accessor of another property?
this code in main.m
[[self note] setValue:@HELLO WORLD forKey:@category];
NSNumber *tmpVal = [NSNumber numberWithBool:![[[self note]
valueForKey:@isEncrypted] boolValue]]; // if I type po [self note] I see
the note description
[[self note] setValue:tmpVal forKey:@isEncrypted]; // if I type po [self
note] after this I get EXEC_BAD_ACCESS
The if statement in the accessor is causing the problem:
- (NSString *)category {
NSString * tmpValue;
[self willAccessValueForKey:@category];
tmpValue = [self primitiveCategory];
[self didAccessValueForKey:@category];
if ([[self valueForKey:@isEncrypted] boolValue]) { // THIS IS CAUSING
THE PROBLEM
// code to decrypt tmpValue
}
return tmpValue;
}
No answer, but a couple of points:
-- What happens if you write 'note.isEncrypted' (or '[note isEncrypted]')
instead of '[note valueForKey: @isEncrypted]'?
-- What happens if you code your own custom accessors for isEncrypted, like
you've done for category?
-- EXC_BAD_ACCESS is often a symptom of a memory management problem. Is there a
problem with the object being returned by '[self note]'? You didn't show code
for where this is implemented. It's possible that you failed to retain the
object, or, if you're using garbage collection, returned an object with no
strong references, or perhaps you returned a zombie object.
What happens in the above code if you set first a local variable to '[[self
note] retain]' and use the local variable in place of the other references to
'[self note]'?
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Re: Accessing a managedObject property from within an accessor of another property
Quincey,
Thanks for relying. It's good to have another developer to talk this thru with.
1) customer accessors for isEncrypted didn't work (I have a set exactly like
category)
2) I'm using garbage collection
3) I tried [note isEncrypted] same error
4) i tried using a local ivar i..e Note *thisNote = [self note], no change
I've been trying these variations for days.
On Feb 22, 2011, at 12:44 PM, Quincey Morris wrote:
On Feb 22, 2011, at 06:19, Brad Stone wrote:
I've been trying for days to determine why I get EXC_BAD_ACCESS when I try
to access a managedObject property from within an accessor of another
property?
this code in main.m
[[self note] setValue:@HELLO WORLD forKey:@category];
NSNumber *tmpVal = [NSNumber numberWithBool:![[[self note]
valueForKey:@isEncrypted] boolValue]]; // if I type po [self note] I see
the note description
[[self note] setValue:tmpVal forKey:@isEncrypted]; // if I type po [self
note] after this I get EXEC_BAD_ACCESS
The if statement in the accessor is causing the problem:
- (NSString *)category {
NSString * tmpValue;
[self willAccessValueForKey:@category];
tmpValue = [self primitiveCategory];
[self didAccessValueForKey:@category];
if ([[self valueForKey:@isEncrypted] boolValue]) { // THIS IS CAUSING
THE PROBLEM
// code to decrypt tmpValue
}
return tmpValue;
}
No answer, but a couple of points:
-- What happens if you write 'note.isEncrypted' (or '[note isEncrypted]')
instead of '[note valueForKey: @isEncrypted]'?
-- What happens if you code your own custom accessors for isEncrypted, like
you've done for category?
-- EXC_BAD_ACCESS is often a symptom of a memory management problem. Is there
a problem with the object being returned by '[self note]'? You didn't show
code for where this is implemented. It's possible that you failed to retain
the object, or, if you're using garbage collection, returned an object with
no strong references, or perhaps you returned a zombie object.
What happens in the above code if you set first a local variable to '[[self
note] retain]' and use the local variable in place of the other references to
'[self note]'?
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Re: Accessing a managedObject property from within an accessor of another property
On Feb 22, 2011, at 10:10, Brad Stone wrote: 2) I'm using garbage collection Then my money's on a memory management error with the [self note] object. Can you show the code for [self note] and/or show the strong reference that keeps it alive? ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
Re: Accessing a managedObject property from within an accessor of another property
On Feb 22, 2011, at 10:10, Brad Stone wrote: 2) I'm using garbage collection Also, it's worth checking that you really have garbage collection turned on. It's easy mistake to turn it on in the project build settings and not realize that the target settings turn it off. The symptoms you've been describing are exactly consistent with this. ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
Re: Accessing a managedObject property from within an accessor of another property
On Feb 22, 2011, at 3:19 PM, Brad Stone wrote:
I've been trying for days to determine why I get EXC_BAD_ACCESS when I try to
access a managedObject property from within an accessor of another property?
Could you post the stack trace? Just for debugging purposed: What happens if
you define another method (not an CoreData-Property)
like:
- (NSString*) categoryPlain
{
NSString* categoryEncryptedOrNot = self.category;
if ([self.isEncrypted boolValue]) {
// decrypt
return decryptedCategory;
}
return categoryEncryptedOrNot;
}
and leave category as a @dynamic-property. Maybe CoreDate gets confused if
you retrieve the value, but change
it after your didAccessValueForKey:-message send
Cheers,
Felix
this code in main.m
[[self note] setValue:@HELLO WORLD forKey:@category];
NSNumber *tmpVal = [NSNumber numberWithBool:![[[self note]
valueForKey:@isEncrypted] boolValue]]; // if I type po [self note] I see
the note description
[[self note] setValue:tmpVal forKey:@isEncrypted]; // if I type po [self
note] after this I get EXEC_BAD_ACCESS
The if statement in the accessor is causing the problem:
- (NSString *)category {
NSString * tmpValue;
[self willAccessValueForKey:@category];
tmpValue = [self primitiveCategory];
[self didAccessValueForKey:@category];
if ([[self valueForKey:@isEncrypted] boolValue]) { // THIS IS CAUSING
THE PROBLEM
// code to decrypt tmpValue
}
return tmpValue;
}
When I replace: if ([[self valueForKey:@isEncrypted] boolValue]) with if (1
== 2 ) or if (1 == 1 ) it works
FYI: in my .h file @property (nonatomic, retain) NSNumber * isEncrypted; and
@dynamic isEncrypted; in .m___
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--
Mit freundlichen Grüßen,
Felix Franz
Lead Software Engineer
ERGOSIGN GmbH
Europa-Allee 12
66113 Saarbrücken
Phone: +49 681 98 84 12 14
Fax: +49 681 98 84 12 10
www.ergosign.de
HRB 11850
Amtsgericht Saarbrücken
Geschäftsführung:
Dr. Marcus Plach
Prof. Dr. Dieter Wallach
Sitz der Gesellschaft:
Saarbrücken
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Re: Accessing a managedObject property from within an accessor of another property
On Feb 22, 2011, at 12:21, Brad Stone wrote: I'm assuming since I can successfully change the string in category my reference to [self note] is OK. This is an absolutely false assumption. If, as I'm hypothesizing, [self note] is returning a zombie object (or it becomes a zombie object after the value is returned), there will be a timing window before undeath == death. During that window, the object may appear to function perfectly normally. If you don't want this to take more days of debugging, you need to stop flailing, and *prove* that [self note] is alive. That could be difficult since the debugger seems to have proof that it's not. If you can prove [self note] is alive, then you need to look elsewhere -- the failing property reference may only be the place where the error becomes apparent, and may not itself have any role in the error. So, again, how are you getting the value for [self note]? And what is its address? (Its 'p (void*)' value, not its 'po' value, if you want to think in GDB terms.) 0x7fff5f3ffd80 doesn't look like a typical 64-bit pointer address. (I have a vague recollection of a past thread about GC XORing something into dead pointer values, producing numbers like this, but I may be remembering something irrelevant.) Note also that 0x7fff843748d7 in _CFArrayReplaceValues () in the debugger output tends to suggest that [self note] is mucking about changing arrays. And I agree with the earlier poster who suggested you get it to fail in code and then post a real backtrace. ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
Re: Accessing a managedObject property from within an accessor of another property
In my Note entity:
self = (Note *)0x20027bda0
In my .h file have this property defined: @property (nonatomic, retain)
NSNumber * isFlagged; and this in .m @dynamic isFlagged; and no custom accessors
New code in my Note entity:
- (void)setIsEncrypted:(NSNumber *)value {
// see po #1 which I typed here
[self willChangeValueForKey:@isFlagged];
[self setPrimitiveValue:value forKey:@isFlagged];
[self didChangeValueForKey:@isFlagged];
// see po #2 which I typed here
[self willChangeValueForKey:@isEncrypted];
[self setPrimitiveValue:value forKey:@isEncrypted];
[self didChangeValueForKey:@isEncrypted];
// see po #3 which I typed here
}
po #1
po self
Note uid:319649395851582
category:None
isFlagged:0
isEncrypted:0
po #2
po self
Note uid:319649395851582
category:None
isFlagged:1
isEncrypted:0
po #3
po self
Breakpoint 28, -[SRMainWindowController toggleLock:] (self=0x2000df5e0,
_cmd=0x1000a9239, sender=0x2000df5e0) at SRMainWindowController.m:2897
2897[note setIsEncrypted:[NSNumber numberWithBool:YES]];
The program being debugged stopped while in a function called from GDB.
When the function (_NSPrintForDebugger) is done executing, GDB will silently
stop (instead of continuing to evaluate the expression containing
the function call).
Here's a backtrace right after po #3 before I'm out of setIsEncrypted
backtrace
#0 -[SRMainWindowController toggleLock:] (self=0x2000df5e0, _cmd=0x1000a9239,
sender=0x2000df5e0) at SRMainWindowController.m:2897
#1 0x00010002dae9 in -[SRMainWindowController getEncryptionKey]
(self=0x2000df5e0, _cmd=0x1000a7210) at SRMainWindowController.m:2948
#2 0x000198d2 in -[Note category] (self=0x20027bda0,
_cmd=0x7fff85450184) at Note.m:257
#3 0x000189c8 in -[Note description] (self=0x20027bda0,
_cmd=0x7fff83c821e8) at Note.m:56
#4 0x7fff868a386b in _NSPrintForDebugger ()
#5 function called from gdb
#6 -[Note setIsEncrypted:] (self=0x20027bda0, _cmd=0x1000a6eb8,
value=0x7fff70886280) at Note.m:206
#7 0x00010002d5c9 in -[SRMainWindowController toggleLock:]
(self=0x2000df5e0, _cmd=0x1000a9239, sender=0x2000867e0) at
SRMainWindowController.m:2897
#8 0x7fff83b2afbf in -[NSToolbarButton sendAction:to:] ()
#9 0x7fff8379c135 in -[NSToolbarItemViewer mouseDown:] ()
#10 0x7fff8368934f in -[NSWindow sendEvent:] ()
#11 0x7fff835bea86 in -[NSApplication sendEvent:] ()
#12 0x7fff835554da in -[NSApplication run] ()
#13 0x7fff8354e1a8 in NSApplicationMain ()
#14 0x00016b60 in main (argc=1, argv=0x7fff5fbff628) at
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Re: Accessing a managedObject property from within an accessor of another property
SCENARIO 1:
The thread is:
0 - [SRMainWindowController toggleLock:] //self = (SRMainWindowController *)
0x20009d440
1-[NSToolbarButton sendAction:to:]
- (IBAction)toggleLock:(id)sender {
NSError *fetchError = nil;
NSArray *fetchResults;
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription
entityForName:@Note inManagedObjectContext:[self managedObjectContext]];
[fetchRequest setEntity:entity];
fetchResults = [[self managedObjectContext]
executeFetchRequest:fetchRequest error:fetchError];
Note *note = nil;
if (fetchRequest != nil [fetchResults count] == 1) {
note = [fetchResults objectAtIndex:index]; //note = (Note
*)0x20027bfe0
}
if (note) {
[note setIsEncrypted:[NSNumber numberWithBool:YES]]; // see below
}
}
When I jump into note setIsEncrypted:[NSNumber numberWithBool:YES]]; in the
Note managedObject
self = (Note *)0x20027bfe0 // same as above
value = (NSCFBoolean *) 0x7fff70886280
po self
Note uid:319649395851582
category:None
isEncrypted:0
isFlagged:0
(gdb)
- (void)setIsEncrypted:(NSNumber *)value {
[self willChangeValueForKey:@isEncrypted];
[self setPrimitiveValue:value forKey:@isEncrypted];
[self didChangeValueForKey:@isEncrypted];
// see backtrace
}
As soon as I po after the setPrimitive I get:
Breakpoint 26, -[SRMainWindowController toggleLock:] (self=0x20009d440,
_cmd=0x1000a92b1, sender=0x20009d440) at SRMainWindowController.m:2891
2891if (fetchRequest != nil [fetchResults count] == 1) {
The program being debugged stopped while in a function called from GDB.
When the function (_NSPrintForDebugger) is done executing, GDB will silently
stop (instead of continuing to evaluate the expression containing
the function call).
#0 -[Note setIsEncrypted:] (self=0x2000b7600, _cmd=0x1000a6eb8,
value=0x7fff70886280) at Note.m:206
#1 0x00010002d5c9 in -[SRMainWindowController toggleLock:]
(self=0x200078f80, _cmd=0x1000a9239, sender=0x2000a0c20) at
SRMainWindowController.m:2897
#2 0x7fff83b2afbf in -[NSToolbarButton sendAction:to:] ()
#3 0x7fff8379c135 in -[NSToolbarItemViewer mouseDown:] ()
#4 0x7fff8368934f in -[NSWindow sendEvent:] ()
#5 0x7fff835bea86 in -[NSApplication sendEvent:] ()
#6 0x7fff835554da in -[NSApplication run] ()
#7 0x7fff8354e1a8 in NSApplicationMain ()
#8 0x00016b60 in main (argc=1, argv=0x7fff5fbff628) at main.m:13
SCENARIO 2:
I created a second scenario as a test to try to shed more light. Scenario 1
and scenario 2 are **exactly** the same but I'm setting another NSNumber,
isFlagged to YES in the setIsEncrypted accessor and it gets set correctly
without an exception but isEncrypted still causes one.
In SRMainWindowController:
self = (SRMainWindowController *)0x2000df5e0
note = (Note *)0x20027bda0
see earlier email for second
part___
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Re: Accessing a managedObject property from within an accessor of another property
That's a lot of information you posted. :) Unfortunately, *based on the posted information* there's nothing obviously wrong except that you've shot yourself in the foot using the debugger. Let's look, for example, at what one of the backtraces is telling you. You triggered this by typing 'po self' in the debugger: On Feb 22, 2011, at 19:34, Brad Stone wrote: Breakpoint 28, -[SRMainWindowController toggleLock:] (self=0x2000df5e0, _cmd=0x1000a9239, sender=0x2000df5e0) at SRMainWindowController.m:2897 2897 [note setIsEncrypted:[NSNumber numberWithBool:YES]]; The program being debugged stopped while in a function called from GDB. When the function (_NSPrintForDebugger) is done executing, GDB will silently stop (instead of continuing to evaluate the expression containing the function call). A function called from the debugger as a result of 'po self' failed. What function? It's not clear yet, but it *is* clear what failed -- that function directly or indirectly called 'toggleLock:' *again* -- the method you were in when you started all this debugging activity. Why did it stop? It hit the breakpoint that you put in that code. This backtrace is enlightening, unlike the earlier ones, because it shows what the debugger was trying to do: Here's a backtrace right after po #3 before I'm out of setIsEncrypted backtrace #0 -[SRMainWindowController toggleLock:] (self=0x2000df5e0, _cmd=0x1000a9239, sender=0x2000df5e0) at SRMainWindowController.m:2897 #1 0x00010002dae9 in -[SRMainWindowController getEncryptionKey] (self=0x2000df5e0, _cmd=0x1000a7210) at SRMainWindowController.m:2948 #2 0x000198d2 in -[Note category] (self=0x20027bda0, _cmd=0x7fff85450184) at Note.m:257 #3 0x000189c8 in -[Note description] (self=0x20027bda0, _cmd=0x7fff83c821e8) at Note.m:56 The debugger was trying to execute [note description], which is what it does to get a description to display as a result of 'po note'. Normally, the standard 'description' in NSObject is called, which just prints the address of the object and its class. You, apparently have overridden 'description' in the Note class, and it apparently invokes 'category', which invokes '-[SRMainWindowController getEncryptionKey]', which invokes 'toggleLock:', which is why it hits the breakpoint again. Note that (apparently) if isEncrypted is NO, then 'getEncryptionKey' isn't invoked, and so 'toggleLock' isn't invoked either. That's why setting isFlagged instead didn't crap out in the debugger. Other than indicating an inappropriate design of your 'description' override, there's absolutely no indication of anything wrong here at all. It looks like you've been chasing a chimera. :) Obviously I may be overlooking something, but step 1 is to fix your 'description' method so that it doesn't cause Core Data fetches. #4 0x7fff868a386b in _NSPrintForDebugger () #5 function called from gdb #6 -[Note setIsEncrypted:] (self=0x20027bda0, _cmd=0x1000a6eb8, value=0x7fff70886280) at Note.m:206 #7 0x00010002d5c9 in -[SRMainWindowController toggleLock:] (self=0x2000df5e0, _cmd=0x1000a9239, sender=0x2000867e0) at SRMainWindowController.m:2897 #8 0x7fff83b2afbf in -[NSToolbarButton sendAction:to:] () #9 0x7fff8379c135 in -[NSToolbarItemViewer mouseDown:] () #10 0x7fff8368934f in -[NSWindow sendEvent:] () #11 0x7fff835bea86 in -[NSApplication sendEvent:] () #12 0x7fff835554da in -[NSApplication run] () #13 0x7fff8354e1a8 in NSApplicationMain () #14 0x00016b60 in main (argc=1, argv=0x7fff5fbff628) at main.m:13 ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
