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[perkiset]

This little class is of very little use except to folks that want to use the Ajax Requestor Class and track the master status of requestors on a page.

All you really do is create one of these and create a function to receive the callback (onChange) - then set <this object> as the masterStatus on an Ajax Requestor. Then, whenever a requestor goes busy, or more precisely, when the current page goes from none-busy to at-least-one-busy you'll get called on the onChange event with (true) - then when the page goes from more-than-zero-busy to zero you'll get another callback on onChange as (false). This is specifically here for my article on the Argument Against Ajax.

An example:

Code:

state = new transmitState();
state.onChange = handleStateChange;
ajax1 = new ajaxRequestor();
ajax1.masterState = state;

...

function handleStateChange(newState)
{
if (newState)
{
// Do "We're just now busy" things
} else {
// Do "We're now idle" things
}
}

There's obviously more to throwing the request than that, but this shows how the two are connected. Here's the actual class:

Code:

// ----------------------------------------------------------- //
//                       transmitState                         //
// ----------------------------------------------------------- //
function transmitState() { this.clear(); }

transmitState.prototype.clear = function()
{
this.busyCount = 0;
this.onChange = null;
this.busy = false;
}
transmitState.prototype.handleChange = function(busy)
{
        if (busy) { this.busyCount++; }
        if (!busy) { this.busyCount--; }
        if (this.busyCount < 0) { this.busyCount = 0; }
        if (this.busyCount)
        {
                if (!this.busy) { if (this.onChange) { this.onChange(true); } }
                this.busy = true;
        } else {
                if (this.busy) { if (this.onChange) { this.onChange(false); } }
                this.busy = false;
        }
}

/p