ionic-framework/js/utils/events.js

/**
 * ion-events.js
 *
 * Author: Max Lynch <max@drifty.com>
 *
 * Framework events handles various mobile browser events, and
 * detects special events like tap/swipe/etc. and emits them
 * as custom events that can be used in an app.
 *
 * Portions lovingly adapted from github.com/maker/ratchet and github.com/alexgibson/tap.js - thanks guys!
 */

(function(ionic) {

  // Custom event polyfill
  if(!window.CustomEvent) {
    (function() {
      var CustomEvent;

      CustomEvent = function(event, params) {
        var evt;
        params = params || {
          bubbles: false,
          cancelable: false,
          detail: undefined
        };
        try {
          evt = document.createEvent("CustomEvent");
          evt.initCustomEvent(event, params.bubbles, params.cancelable, params.detail);
        } catch (error) {
          // fallback for browsers that don't support createEvent('CustomEvent')
          evt = document.createEvent("Event");
          for (var param in params) {
            evt[param] = params[param];
          }
          evt.initEvent(event, params.bubbles, params.cancelable);
        }
        return evt;
      };

      CustomEvent.prototype = window.Event.prototype;

      window.CustomEvent = CustomEvent;
    })();
  }


  /**
   * @ngdoc utility
   * @name ionic.EventController
   * @module ionic
   */
  ionic.EventController = {
    VIRTUALIZED_EVENTS: ['tap', 'swipe', 'swiperight', 'swipeleft', 'drag', 'hold', 'release'],

    /**
     * @ngdoc method
     * @name ionic.EventController#trigger
     * @alias ionic.trigger
     * @param {string} eventType The event to trigger.
     * @param {object} data The data for the event. Hint: pass in
     * `{target: targetElement}`
     * @param {boolean=} bubbles Whether the event should bubble up the DOM.
     * @param {boolean=} cancelable Whether the event should be cancelable.
     */
    // Trigger a new event
    trigger: function(eventType, data, bubbles, cancelable) {
      var event = new CustomEvent(eventType, {
        detail: data,
        bubbles: !!bubbles,
        cancelable: !!cancelable
      });

      // Make sure to trigger the event on the given target, or dispatch it from
      // the window if we don't have an event target
      data && data.target && data.target.dispatchEvent(event) || window.dispatchEvent(event);
    },

    /**
     * @ngdoc method
     * @name ionic.EventController#on
     * @alias ionic.on
     * @description Listen to an event on an element.
     * @param {string} type The event to listen for.
     * @param {function} callback The listener to be called.
     * @param {DOMElement} element The element to listen for the event on.
     */
    on: function(type, callback, element) {
      var e = element || window;

      // Bind a gesture if it's a virtual event
      for(var i = 0, j = this.VIRTUALIZED_EVENTS.length; i < j; i++) {
        if(type == this.VIRTUALIZED_EVENTS[i]) {
          var gesture = new ionic.Gesture(element);
          gesture.on(type, callback);
          return gesture;
        }
      }

      // Otherwise bind a normal event
      e.addEventListener(type, callback);
    },

    /**
     * @ngdoc method
     * @name ionic.EventController#off
     * @alias ionic.off
     * @description Remove an event listener.
     * @param {string} type
     * @param {function} callback
     * @param {DOMElement} element
     */
    off: function(type, callback, element) {
      element.removeEventListener(type, callback);
    },

    /**
     * @ngdoc method
     * @name ionic.EventController#onGesture
     * @alias ionic.onGesture
     * @description Add an event listener for a gesture on an element.
     * @param {string} eventType The gesture event to listen for.
     * @param {function(e)} callback The function to call when the gesture
     * happens.
     * @param {DOMElement} element The angular element to listen for the event on.
     */
    onGesture: function(type, callback, element) {
      var gesture = new ionic.Gesture(element);
      gesture.on(type, callback);
      return gesture;
    },

    /**
     * @ngdoc method
     * @name ionic.EventController#offGesture
     * @alias ionic.offGesture
     * @description Remove an event listener for a gesture on an element.
     * @param {string} eventType The gesture event.
     * @param {function(e)} callback The listener that was added earlier.
     * @param {DOMElement} element The element the listener was added on.
     */
    offGesture: function(gesture, type, callback) {
      gesture.off(type, callback);
    },

    handlePopState: function(event) {
    },
  };


  // Map some convenient top-level functions for event handling
  ionic.on = function() { ionic.EventController.on.apply(ionic.EventController, arguments); };
  ionic.off = function() { ionic.EventController.off.apply(ionic.EventController, arguments); };
  ionic.trigger = ionic.EventController.trigger;//function() { ionic.EventController.trigger.apply(ionic.EventController.trigger, arguments); };
  ionic.onGesture = function() { return ionic.EventController.onGesture.apply(ionic.EventController.onGesture, arguments); };
  ionic.offGesture = function() { return ionic.EventController.offGesture.apply(ionic.EventController.offGesture, arguments); };

})(window.ionic);