RemoveNotification未被调用

Question

我在代码中使用NSNotificationCenter。

[[NSNotificationCenter defaultCenter]addObserverForName:@"NextIndexNotification" object:nil queue:[NSOperationQueue mainQueue] usingBlock:^(NSNotification *note) {

    [self receiveTestNotification:note];
    [[NSNotificationCenter defaultCenter] removeObserver:note];


}];

- (void)receiveTestNotification:(NSNotification *) notification
{
    NSDictionary *userInfo = notification.userInfo;
    NSString *strServerResultID = [userInfo objectForKey:@"valServerResultID"];
}

////我在这里添加通知中心......

            dispatch_async(dispatch_get_main_queue(),^{
                NSDictionary *userInfo = [NSDictionary dictionaryWithObject:[NSString stringWithFormat:@"%@",[[PerformXMLXPathQuery(responseData,xPathQuery) objectAtIndex:0] valueForKey:kNodeContent]] forKey:@"valServerResultID"];
                [[NSNotificationCenter defaultCenter] postNotificationName:@"NextIndexNotification" object:self userInfo:userInfo];

            });

在此代码中，删除通知未被调用，我的代码移动到无限循环。

我在哪里做错了？

Answer 1

不是传递note（通知本身而不是观察者），而是将addObserverForName调用的返回值传递给removeObserver，如下所示：

__block id observer = [[NSNotificationCenter defaultCenter] addObserverForName:@"NextIndexNotification" 
                      object:nil 
                       queue:[NSOperationQueue mainQueue] 
                  usingBlock:^(NSNotification *note)
{
    [self receiveTestNotification:note];
    [[NSNotificationCenter defaultCenter] removeObserver:observer];
}];

Answer 2

试试     [[NSNotificationCenter defaultCenter] removeObserver：nil];

Answer 3

使用blocks删除通知。

[[NSNotificationCenter defaultCenter] removeObserver:self];