Question

I ve a class called AppController.h/m I want to make something when the NSNotificationDidResignActiveNotification is sent. So i wrote this code in AppController.m:

-(void) initialize(){
    [[NSNotificationCenter defaultCenter] addObserver:self
                                                 selector:@selector(applicationDidResignActive:)
                                                     name:NSApplicationDidResignActiveNotification
                                                   object:nil ];
}

之后

-(void) applicationDidResignActive (NSNotification*) note{
    NSBeep();
}

问题在于,该方法在康塞莱实施,而且:

+[AppController applicationDidResignActive:]: unrecognized selector sent to class 0x61c4

I can t get where the problem is: could you help me?
Thank you!

Answer 1

。我不知道这一点,但似乎在使用一种班级方法的甄选者时,也假定甄选者将是一种班级方法(理由良好)。主计长采用一种称为<代码>的申请方法 Did Resignive ,但并非一类方法。

而不是在<代码>+初始化上登记通知,而是在<代码>-init上登记。

- (void)init
{
    [[NSNotificationCenter defaultCenter] addObserver:self
                                                 selector:@selector(applicationDidResignActive:)
                                                     name:NSApplicationDidResignActiveNotification
                                                   object:nil ];
}

友情链接