objective-c - Cocoa 中未调用我的委托(delegate)操作

Question

我有一个类有它的委托(delegate):

@protocol SNIRCControllerDelegate

- (void) serverTalked:(id)data;

@end

@interface SNIRCController : NSObject <NSStreamDelegate> {
    id<SNIRCControllerDelegate> delegate;

}
- (void) setDelegate:(id<SNIRCControllerDelegate>)_delegate;
- (void) test;
@end

实现:

@implementation SNIRCController

- (void) setDelegate:(id<SNIRCControllerDelegate>)_delegate {
    _delegate = delegate;
}
- (void) test {
    [delegate serverTalked:@"test"];

}

但由于某些原因 [delegate serverTalked:@"test"]; 没有调用委托(delegate):/ 这就是我在 AppDelegate 上的做法:

@interface AppDelegate : NSObject <NSApplicationDelegate, NSStreamDelegate, SNIRCControllerDelegate> {

    IBOutlet NSTextView *logField;
    SNIRCController *ircController;
}

@property (assign) IBOutlet NSWindow *window;

-(void)writeToLog:(NSString*)data;

@end

@implementation AppDelegate

@synthesize window = _window;

- (void)applicationDidFinishLaunching:(NSNotification *)aNotification
{
    ircController = [[SNIRCController alloc] init];
    [ircController setDelegate:self];

    [ircController test];
}
- (void) serverTalked:(id)data {
    NSLog(@"got called :D");
}

-(void)writeToLog:(NSString*)data {

    NSAttributedString *stringToAppend = [[NSAttributedString alloc] initWithString:[NSString stringWithFormat:@"%@\n", data]];
    [[logField textStorage] appendAttributedString:stringToAppend];

}

但是 serverTalked: 没有被调用 :( 我做错了什么？

Answer 1

在您的 setDelegate: 实现中，这:

_delegate = delegate;

应该是:

delegate = _delegate;

你搞糊涂了，调换了 ivar 和参数。造成混淆的原因可能是下划线前缀更常用于 ivars。在您的例子中，它是带有下划线前缀的参数。