CPDistributedMessagingCenter

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Revision as of 18:40, 22 September 2009 by KennyTM~ (talk | contribs)
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CPDistributedMessagingCenter is a simple wrapper over the existing messaging facilities in the operating system. It provides two-way communication between different processes using simple messages and dictionaries. All dictionaries transferred must be serializable as a property list.

Server

-(id)init... {
...

  CPDistributedMessagingCenter *messagingCenter;
  // Center name must be unique, recommend using application identifier.
  messagingCenter = [CPDistributedMessagingCenter centerNamed:@"unique.name.for.messaging.center"];
  [messagingCenter runServerOnCurrentThread];

  // Register Messages
  [messagingCenter registerForMessageName:@"messageThatHasInfo" target:self selector:@selector(handleMessageNamed:withUserInfo:)];
  [messagingCenter registerForMessageName:@"message" target:self selector:@selector(handleSimpleMessageNamed:)];

...
}

- (NSDictionary *)handleMessageNamed:(NSString *)name withUserInfo:(NSDictionary *)userinfo {
    // Process userinfo (simple dictionary) and return a dictionary (or nil)
}

- (void)handleSimpleMessageNamed:(NSString *)name {
    // ...
}

Client

CPDistributedMessagingCenter *messagingCenter;
messagingCenter = [CPDistributedMessagingCenter centerNamed:@"unique.name.for.messaging.center"];

// One-way (message only)
[messagingCenter sendMessageName:@"message" userInfo:/* optional dictionary. in this example it will be ignored. */];

// Two-way (wait for reply)
NSDictionary *reply;
reply = [messagingCenter sendMessageAndReceiveReplyName:@"messageThatHasInfo" userInfo:/* optional dictionary */];

Header