我有四节课,让我们假设A,B,C和d,现在我的等级B,C,d需要观察A类的价值,并得到通知当值改变时。我观察到在B类的价值,我不能够在其他两个班得到通知说,C和D. 在此先感谢..核心价值观测添加三个观察员观察一个类值
- (void)viewDidLoad
{
[super viewDidLoad];
newClassAToBeObserved=[[ClassATobeObserved alloc]init];
[newClassAToBeObserved addObserver:self forKeyPath:@"StatusToken" options:NSKeyValueObservingOptionNew context:NULL];
ClassB*classB=[[ClassB alloc]init];
[classB func];
ClassC*classc=[[ClassC alloc]init];
[classc func];
}
-(void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context
{
if ([keyPath isEqualToString:@"StatusToken"])
{
NSLog(@"changed value is : %@",[object valueForKeyPath:keyPath]);
}
}
-(IBAction)ClickIt
{
[newClassAToBeObserved setStatusToken:@"TokenExpired"];
NSLog(@"Value-->%@",newClassAToBeObserved.StatusToken);
}
显示代码。什么可行,什么不可行,有什么区别? – Wain
只是一个分,我会添加代码现在 –
你只需要添加'self'作为观察员...... – Wain