Re: Life of instance variables?

[Albert Chun-Chieh Huang]

Kim Shrier <kim@tinker.com> writes:

> It would be nice ro see the source of the init method for Node and MyNode.
> I am going to assume your code is something like this:
> 
[stuff deleted]
> 
> If you have done that, your instance variable will be properly initialized
> and its value should be valid as long as the instance is not freed. Any
> value you set with setNodeState should stay around until you change it with
> setNodeState.
> 
> If you are seeing a value of 14 for state and you are sure that you are not
> setting it to 14 after you have set it to 1, then I would make sure that you
> are passing the instance of MyNode whose state was set to 1 into your
> Channel
> instance.
> 
> Kim

Dear Kim,
    Thanks for your reply. My -init is like this:
MyNode:
- initNodeWithAddress: (unsigned int)theAddress 
{
    self = [super initNodeWithAddress: theAddress];
    // Other portion of initialization
    return self;
}

Node:
- initNodeWithAddress: (unsigned int)theAddress 
{
    self = [super init];
    state = 14;
    // other portion of initialization
    return self;
}

And one thing should be noted here, but I don't know if it's
important. In Channel, the instance of MyNode is from an NSArray,
which is an id array of instances of MyNode, and it is derived from:

// In Node
[theChannel registerAsReceiver: self 
            atFrequency: theFreq
            fromFrequency: registeredFreq];
NSLog(@"Node %x state = %d", theBD_ADDR, state);

theChannel is an instance of Channel.

The situation I mentioned only occurs at -receivePacket: method. The
NSLog line works well, I mean, state is 1. But later when theChannel
issue the statement [aNode receivePacket: aPacket], the value of state
is not what I expect. Is it possible that I misuse the variable
"self"?

-- 
Chun-Chieh Huang, aka Albert   | E-mail: jjhuang AT cm.nctu.edu.tw
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