src/instance.js
/**
* @module hammer
*/
/**
* create new hammer instance
* all methods should return the instance itself, so it is chainable.
*
* @class Instance
* @constructor
* @param {HTMLElement} element
* @param {Object} [options={}] options are merged with `Hammer.defaults`
* @return {Hammer.Instance}
*/
Hammer.Instance = function(element, options) {
var self = this;
// setup HammerJS window events and register all gestures
// this also sets up the default options
setup();
/**
* @property element
* @type {HTMLElement}
*/
this.element = element;
/**
* @property enabled
* @type {Boolean}
* @protected
*/
this.enabled = true;
/**
* options, merged with the defaults
* options with an _ are converted to camelCase
* @property options
* @type {Object}
*/
Utils.each(options, function(value, name) {
delete options[name];
options[Utils.toCamelCase(name)] = value;
});
this.options = Utils.extend(Utils.extend({}, Hammer.defaults), options || {});
// add some css to the element to prevent the browser from doing its native behavoir
if(this.options.behavior) {
Utils.toggleBehavior(this.element, this.options.behavior, false);
}
/**
* event start handler on the element to start the detection
* @property eventStartHandler
* @type {Object}
*/
this.eventStartHandler = Event.onTouch(element, EVENT_START, function(ev) {
if(self.enabled && ev.eventType == EVENT_START) {
Detection.startDetect(self, ev);
} else if(ev.eventType == EVENT_TOUCH) {
Detection.detect(ev);
}
});
/**
* keep a list of user event handlers which needs to be removed when calling 'dispose'
* @property eventHandlers
* @type {Array}
*/
this.eventHandlers = [];
};
Hammer.Instance.prototype = {
/**
* bind events to the instance
* @method on
* @chainable
* @param {String} gestures multiple gestures by splitting with a space
* @param {Function} handler
* @param {Object} handler.ev event object
*/
on: function onEvent(gestures, handler) {
var self = this;
Event.on(self.element, gestures, handler, function(type) {
self.eventHandlers.push({ gesture: type, handler: handler });
});
return self;
},
/**
* unbind events to the instance
* @method off
* @chainable
* @param {String} gestures
* @param {Function} handler
*/
off: function offEvent(gestures, handler) {
var self = this;
Event.off(self.element, gestures, handler, function(type) {
var index = Utils.inArray({ gesture: type, handler: handler });
if(index !== false) {
self.eventHandlers.splice(index, 1);
}
});
return self;
},
/**
* trigger gesture event
* @method trigger
* @chainable
* @param {String} gesture
* @param {Object} [eventData]
*/
trigger: function triggerEvent(gesture, eventData) {
// optional
if(!eventData) {
eventData = {};
}
// create DOM event
var event = Hammer.DOCUMENT.createEvent('Event');
event.initEvent(gesture, true, true);
event.gesture = eventData;
// trigger on the target if it is in the instance element,
// this is for event delegation tricks
var element = this.element;
if(Utils.hasParent(eventData.target, element)) {
element = eventData.target;
}
element.dispatchEvent(event);
return this;
},
/**
* enable of disable hammer.js detection
* @method enable
* @chainable
* @param {Boolean} state
*/
enable: function enable(state) {
this.enabled = state;
return this;
},
/**
* dispose this hammer instance
* @method dispose
* @return {Null}
*/
dispose: function dispose() {
var i, eh;
// undo all changes made by stop_browser_behavior
if(this.options.behavior) {
Utils.toggleBehavior(this.element, this.options.behavior, true);
}
// unbind all custom event handlers
for(i = -1; (eh = this.eventHandlers[++i]);) {
Utils.off(this.element, eh.gesture, eh.handler);
}
this.eventHandlers = [];
// unbind the start event listener
Event.off(this.element, EVENT_TYPES[EVENT_START], this.eventStartHandler);
return null;
}
};