util-events.js

/**

* util-events.js - The minimal events support

*/

 

var events = data.events = {}

 

// Bind event

seajs.on = function(name, callback) {

  var list = events[name] || (events[name] = [])

  list.push(callback)

  return seajs

}

 

// Remove event. If `callback` is undefined, remove all callbacks for the

// event. If `event` and `callback` are both undefined, remove all callbacks

// for all events

seajs.off = function(name, callback) {

  // Remove *all* events

  if (!(name || callback)) {

    events = data.events = {}

    return seajs

  }

 

  var list = events[name]

  if (list) {

    if (callback) {

      for (var i = list.length - 1; i >= 0; i--) {

        if (list[i] === callback) {

          list.splice(i, 1)

        }

      }

    }

    else {

      delete events[name]

    }

  }

 

  return seajs

}

 

// Emit event, firing all bound callbacks. Callbacks receive the same

// arguments as `emit` does, apart from the event name

var emit = seajs.emit = function(name, data) {

  var list = events[name], fn

 

  if (list) {

    // Copy callback lists to prevent modification

    list = list.slice()

 

    // Execute event callbacks, use index because it's the faster.

    for(var i = 0, len = list.length; i < len; i++) {

      list[i](data)

    }

  }

 

  return seajs

}