Question

I have the following call which runs a method within a cacheListener object asynchronously:

ohttp.asyncOpenCacheEntry(url, 4, cacheListener);

Here is what the callback object/function looks like:

var cacheListener = {
    onCacheEntryAvailable: function(arg1, arg2, arg3) {
    // do something.
    }
}

What I’m trying to do is add an extra argument to that callback. I’ve tried appending a third argument at the end of the call and then in the function definition, but it won’t get passed properly like this (myArg at the end):

    ohttp.asyncOpenCacheEntry(url, 4, cacheListener, myArg);

Here is what the callback object/function looks like with the extra argument:

var cacheListener = {
    onCacheEntryAvailable: function(arg1, arg2, arg3, myArg) {
    // do something.
    }
}

myArg, as expectable, isn’t passed, and I’m not sure how to make a construct that would allow for the argument to be passed properly.

Thanks for your help,

Answer 1

You’re going to have to wrap it up if you don’t control the code that’s using your callback. Something like this:

ohttp.asyncOpenCacheEntry(url, 4, cacheListener, {
    onCacheEntryAvailable: function(arg1, arg2, arg3) {
        cacheListener.onCacheEntryAvailable(arg1, arg2, arg3, myArg);
    }
});

If there are other methods in the callback objects then you’ll have to wrap those too.