What Is -[NSURL _fastCharacterContents]:?
So I'm calling this in a method:
-(id)initWithContentURL:(NSString *)url {
if (self = [super init]) {
NSLog(@"xSheetMusicViewController - %@",url);
// Casting an NSString object pointer to a CFStringRef:
CFStringRef cfString = (CFStringRef)url;
CFURLRef pdfURL = CFBundleCopyResourceURL(CFBundleGetMainBundle(), cfString, NULL, NULL);
pdf = CGPDFDocumentCreateWithURL((CFURLRef)pdfURL);
}
return self;
}
Which crashes right at the NSLog at the line marked:
CFURLRef pdfURL = CFBundleCopyResourceURL(CFBundleGetMainBundle(), cfString, NULL, NULL);
with this wonderful little error I've never seen before. Here's the crash log:
SheetMuse[83550:b603] -[NSURL _fastCharacterContents]: unrecognized selector sent to instance 0x4ec35f0
2011-09-22 17:36:22.921 SheetMuse[83550:b603] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[NSURL _fastCharacterContents]: unrecognized selector sent to instance 0x4ec35f0'
*** Call stack at first throw:
(
0 CoreFoundation 0x011be5a9 __exceptionPreprocess + 185
1 libobjc.A.dylib 0x01312313 objc_exception_throw + 44
2 CoreFoundation 0x011c00bb -[NSObject(NSObject) doesNotRecognizeSelector:] + 187
3 CoreFoundation 0x0112f966 ___forwarding___ + 966
4 CoreFoundation 0x0112f522 _CF_forwarding_prep_0 + 50
5 CoreFoundation 0x010d2857 CFStringGetCharactersPtr + 135
6 CoreFoundation 0x010d6c93 CFStringGetFileSystemRepresentation + 35
7 CoreFoundation 0x01110811 _CFFindBundleResources + 289
8 CoreFoundation 0x0110d961 CFBundleCopyResourceURL + 305
9 SheetMuse 0x00005b19 -[xSheetMusicViewController initWithContentURL:] + 153
10 SheetMuse 0x00009724 -[ExamplesViewController tableView:didSelectRowAtIndexPath:] + 708
11 UIKit 0x00487b68 -[UITableView _selectRowAtIndexPath:animated:scrollPosition:notifyDelegate:] + 1140
12 UIKit 0x0047db05 -[UITableView _userSelectRowAtPendingSelectionIndexPath:] + 219
13 Foundation 0x00b9779e __NSFireDelayedPerform + 441
14 CoreFoundation 0x0119f8c3 __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 19
15 CoreFoundation 0x011a0e74 __CFRunLoopDoTimer + 1220
16 CoreFoundation 0x010fd2c9 __CFRunLoopRun + 1817
17 CoreFoundation 0x010fc840 CFRunLoopRunSpecific + 208
18 CoreFoundation开发者_JAVA百科 0x010fc761 CFRunLoopRunInMode + 97
19 GraphicsServices 0x028a31c4 GSEventRunModal + 217
20 GraphicsServices 0x028a3289 GSEventRun + 115
21 UIKit 0x0041ec93 UIApplicationMain + 1160
22 SheetMuse 0x000028a9 main + 121
23 SheetMuse 0x00002825 start + 53
)
terminate called throwing an exceptionsharedlibrary apply-load-rules all
So, what is this error, and how do I fix it?
EDIT: This question has been solved. Thank you everyone who answered, I was banging my head on the wall trying to figure this out. If you would like, I can give you a mention in the app, seeing as I would like to release it in a few weeks, and your help has ironed out the biggest bug in the code. Again THANK YOU!
-_fastCharacterContents:
is a private method of NSString
. The error you get indicates that the corresponding message was being sent to an NSURL
instance, hence the crash. It looks like the url
parameter that’s being passed to -initWithContentURL:
is an NSURL
, not an NSString
.
Placing
NSLog(@"url is of type %@", [url class]);
at the beginning of the method should tell you the exact class of url
.
I suggest you change your method signature to:
- (void)initWithContentPath:(NSString *)path
in order to make it clear that the method expects a string representing a (relative) path. There are other classes in Cocoa Touch that declare -initWithContentURL:
to receive an NSURL *
argument.
In most cases this sort of error is due to passing the wrong type of object on a call.
How are you calling initWithContentURL? It looks like you might be passing an NSURL that has been (improperly) cast to an NSString.
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