同步处理推送通知操作中的操作

Question

我想通过使用FIFO来同步处理push notification操作。内部：

(void)application:(UIApplication *)application handleActionWithIdentifier:(NSString *)identifier forRemoteNotification:(NSDictionary *)userInfo completionHandler:(void (^)())completionHandler 

我有很多块，我想，当我收到一个动作，我在FIFO添加它（与它的块）。

Answer 1

NSOperationQueue* queue = [[ NSOperationQueue alloc ] init]; 
queue.maxConcurrentOperationCount = 1; 

NSOperation* someOperation = [NSBlockOperation blockOperationWithBlock:^(void) { NSLog(@"Done.");}]; 

if (queue.operations.count != 0) 
    [someOperation addDependency: queue.operations.lastObject]; 

你也可以简单地类别添加到您的NSOperationQueue：

@interface NSOperationQueue (FIFOQueue) 
    - (void)addOperationAfterLast:(NSOperation *)op; 
@end 

@implementation NSOperationQueue (FIFOQueue) 
- (void)addOperationAfterLast:(NSOperation *)op 
    { 
    if (self.maxConcurrentOperationCount != 1) 
     self.maxConcurrentOperationCount = 1; 
     NSOperation* lastOp = self.operations.lastObject; 
    if (lastOp != nil) 
     [op addDependency: lastOp]; 
     [self addOperation:op]; 
    } 
@end 

，并使用[队列addOperationAfterLast：myOperation。

Answer 2

尝试使用这种方法

dispatch_queue_t myQueue = dispatch_queue_create("com.mycompany.myqueue", 0); 
dispatch_async(myQueue, ^{ 
    printf("1"); 
}); 
dispatch_async(myQueue, ^{ 
    printf("2"); 
}); 
dispatch_async(myQueue, ^{ 
    printf("3"); 
}); 
dispatch_async(myQueue, ^{ 
    printf("4"); 
}); 
dispatch_async(myQueue, ^{ 
    printf("5"); 
}); 
// wait for queue to empty 
dispatch_sync(myQueue, ^{ 
    printf("done"); 
});