delegate.js revision 3a1493afa5d204a301f770bf1e95318cf9a7bff8
/**
* Set up a delegated listener container.
* @event delegate
* @param type {string} 'delegate'
* @param fn {string} the function to execute
* @param el {string|node} the element that is the delegation container
* @param event {string} the event type to delegate
* @param spec {string} a selector that must match the target of the
* event.
* @param o optional context object
* @param args 0..n additional arguments that should be provided
* to the listener.
* @return {Event.Handle} the detach handle
* @for YUI
*/
Y.Env.eventAdaptors.delegate = {
on: function(type, fn, el, event, spec, o) {
var ename = 'delegate:' + (Y.Lang.isString(el) ? el : Y.stamp(el)) + event + spec,
a = Y.Array(arguments, 0, true);
// set up the listener on the container
Y.on(event, function(e) {
var targets = e.currentTarget.queryAll(spec),
target = e.target,
passed = false;
if (targets) {
// @TODO we need Node.some
targets.each(function (v, k) {
if ((!passed) && (v == target)) {
Y.fire(ename, e);
passed = true;
}
});
}
}, el);
a[0] = ename;
// remove element, delegation event, and delegation spec from the args
a.splice(2, 3);
// subscribe to the custom event for the delegation spec
return Y.on.apply(Y, a);
}
};