Files
openlayers/src/ol/interaction/touchinteraction.js
2013-09-13 11:23:05 -04:00

152 lines
3.7 KiB
JavaScript

goog.provide('ol.interaction.Touch');
goog.require('goog.asserts');
goog.require('goog.functions');
goog.require('goog.object');
goog.require('ol.MapBrowserEvent');
goog.require('ol.MapBrowserEvent.EventType');
goog.require('ol.Pixel');
goog.require('ol.ViewHint');
goog.require('ol.interaction.Interaction');
/**
* Base class for touch interactions.
* @constructor
* @extends {ol.interaction.Interaction}
*/
ol.interaction.Touch = function() {
goog.base(this);
/**
* @type {boolean}
* @private
*/
this.handled_ = false;
/**
* @type {Object}
* @private
*/
this.trackedTouches_ = {};
/**
* @type {Array.<Object>}
* @protected
*/
this.targetTouches = [];
};
goog.inherits(ol.interaction.Touch, ol.interaction.Interaction);
/**
* @param {Array.<Object>} touches TouchEvents.
* @return {ol.Pixel} Centroid pixel.
*/
ol.interaction.Touch.centroid = function(touches) {
var length = touches.length;
var clientX = 0;
var clientY = 0;
for (var i = 0; i < length; i++) {
clientX += touches[i].clientX;
clientY += touches[i].clientY;
}
return [clientX / length, clientY / length];
};
/**
* @param {ol.MapBrowserEvent} mapBrowserEvent Event.
* @return {boolean} Whether the event is a touchstart, touchmove
* or touchend event.
* @private
*/
ol.interaction.Touch.isTouchEvent_ = function(mapBrowserEvent) {
var type = mapBrowserEvent.type;
return (
type === ol.MapBrowserEvent.EventType.TOUCHSTART ||
type === ol.MapBrowserEvent.EventType.TOUCHMOVE ||
type === ol.MapBrowserEvent.EventType.TOUCHEND);
};
/**
* @param {ol.MapBrowserEvent} mapBrowserEvent Event.
* @private
*/
ol.interaction.Touch.prototype.updateTrackedTouches_ =
function(mapBrowserEvent) {
if (ol.interaction.Touch.isTouchEvent_(mapBrowserEvent)) {
var event = mapBrowserEvent.browserEvent.getBrowserEvent();
if (goog.isDef(event.targetTouches)) {
// W3C touch events
this.targetTouches = event.targetTouches;
} else if (goog.isDef(event.pointerId)) {
// IE pointer event
if (mapBrowserEvent.type == ol.MapBrowserEvent.EventType.TOUCHEND) {
delete this.trackedTouches_[event.pointerId];
} else {
this.trackedTouches_[event.pointerId] = event;
}
this.targetTouches = goog.object.getValues(this.trackedTouches_);
} else {
goog.asserts.fail('unknown touch event model');
}
}
};
/**
* @param {ol.MapBrowserEvent} mapBrowserEvent Event.
* @protected
*/
ol.interaction.Touch.prototype.handleTouchMove = goog.nullFunction;
/**
* @param {ol.MapBrowserEvent} mapBrowserEvent Event.
* @protected
* @return {boolean} Capture dragging.
*/
ol.interaction.Touch.prototype.handleTouchEnd = goog.functions.FALSE;
/**
* @param {ol.MapBrowserEvent} mapBrowserEvent Event.
* @protected
* @return {boolean} Capture dragging.
*/
ol.interaction.Touch.prototype.handleTouchStart = goog.functions.FALSE;
/**
* @inheritDoc
*/
ol.interaction.Touch.prototype.handleMapBrowserEvent =
function(mapBrowserEvent) {
var view = mapBrowserEvent.map.getView();
this.updateTrackedTouches_(mapBrowserEvent);
if (this.handled_) {
if (mapBrowserEvent.type == ol.MapBrowserEvent.EventType.TOUCHMOVE) {
this.handleTouchMove(mapBrowserEvent);
} else if (mapBrowserEvent.type == ol.MapBrowserEvent.EventType.TOUCHEND) {
this.handled_ = this.handleTouchEnd(mapBrowserEvent);
if (!this.handled_) {
view.setHint(ol.ViewHint.INTERACTING, -1);
}
}
}
if (mapBrowserEvent.type == ol.MapBrowserEvent.EventType.TOUCHSTART) {
var handled = this.handleTouchStart(mapBrowserEvent);
if (!this.handled_ && handled) {
view.setHint(ol.ViewHint.INTERACTING, 1);
}
this.handled_ = handled;
}
return true;
};