I'm new to Cocoa and objective C development and I've got a big problem with multithreading:
I've created a class with some member variables of type NSString*. In the init function of the class, I write something into those strings. Now I call a function of the initialized class instance as a new thread and try to read from those member variables. This leads to a crash... Can someone give me a hint as to why this won't work? Here's my code, shrunk down to just the problematic part: ---------- MyClass.h ----------------------------- @interface MyClass: NSObject { @private NSString* baseURL; } - (id) initWithHost: (NSString*) _url; - (void) doSomething: (id) object; @end ---------------------------------------------------------- ---------- MyClass.m ----------------------------- @implementation MyClass - (id) initWithHost: (NSString*) _url { self = [super init]; baseURL = [NSString stringWithString: _url]; return self; } - (void) doSomething: (id) object { NSString *url = [NSString stringWithString: baseURL]; // <-- the crash occurs even when just reading the member } @end ---------------------------------------------------------- I've tried calling the function in the same thread, as well as three different ways of calling it in a seperate thread. Every time there's another thread involved, it crashes when accessing the member variable. If the function doesn't access any members, the code works just fine... instance = [[MyClass alloc] initWithHost: txtHost.text]; [instance doSomething: nil]; // Works [instance performSelectorInBackground: @selector(doSomething:) withObject: nil]; // Doesn't work [[[NSThread alloc] initWithTarget: instance selector: @selector(doSomething:) object: nil] start]; // Doesn't work [NSThread detachNewThreadSelector: @selector(doSomething:) toTarget: instance withObject: nil]; // Doesn't work Thanks, Dennis _______________________________________________ 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 [EMAIL PROTECTED]