Files
openlayers/src/ol/pointer/pointerevent.js
2014-03-14 10:16:25 +01:00

240 lines
7.4 KiB
JavaScript

// Based on https://github.com/Polymer/PointerEvents
// Copyright (c) 2013 The Polymer Authors. All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
goog.provide('ol.pointer.PointerEvent');
//goog.require('goog.events.Event');
goog.require('goog.events');
/**
* This is the constructor for new PointerEvents.
*
* New Pointer Events must be given a type, and an optional dictionary of
* initialization properties.
*
* Due to certain platform requirements, events returned from the constructor
* identify as MouseEvents.
*
* @constructor
* @extends {Event}
* @param {string} inType The type of the event to create.
* @param {Object.<string, ?>=} opt_inDict An optional dictionary of
* initial event properties.
*/
ol.pointer.PointerEvent = function(inType, opt_inDict) {
opt_inDict = opt_inDict || {};
// According to the w3c spec,
// http://www.w3.org/TR/DOM-Level-3-Events/#events-MouseEvent-button
// MouseEvent.button == 0 can mean either no mouse button depressed, or the
// left mouse button depressed.
//
// As of now, the only way to distinguish between the two states of
// MouseEvent.button is by using the deprecated MouseEvent.which property, as
// this maps mouse buttons to positive integers > 0, and uses 0 to mean that
// no mouse button is held.
//
// MouseEvent.which is derived from MouseEvent.button at MouseEvent creation,
// but initMouseEvent does not expose an argument with which to set
// MouseEvent.which. Calling initMouseEvent with a buttonArg of 0 will set
// MouseEvent.button == 0 and MouseEvent.which == 1, breaking the expectations
// of app developers.
//
// The only way to propagate the correct state of MouseEvent.which and
// MouseEvent.button to a new MouseEvent.button == 0 and MouseEvent.which == 0
// is to call initMouseEvent with a buttonArg value of -1.
//
// This is fixed with DOM Level 4's use of buttons
var buttons;
if (opt_inDict.buttons || ol.pointer.PointerEvent.HAS_BUTTONS) {
buttons = opt_inDict.buttons;
} else {
switch (opt_inDict.which) {
case 1: buttons = 1; break;
case 2: buttons = 4; break;
case 3: buttons = 2; break;
default: buttons = 0;
}
}
var e;
if (ol.pointer.PointerEvent.NEW_MOUSE_EVENT) {
e = ol.pointer.PointerEvent.createMouseEvent(inType, opt_inDict);
} else {
e = document.createEvent('MouseEvent');
// import values from the given dictionary
/**
* @type {Object.<string, ?>}
*/
var props = {};
var p;
for (var i = 0; i < ol.pointer.PointerEvent.MOUSE_PROPS.length; i++) {
p = ol.pointer.PointerEvent.MOUSE_PROPS[i];
props[p] = opt_inDict[p] || ol.pointer.PointerEvent.MOUSE_DEFAULTS[i];
}
// define the properties inherited from MouseEvent
e.initMouseEvent(
inType, props.bubbles, props.cancelable, props.view, props.detail,
props.screenX, props.screenY, props.clientX, props.clientY,
props.ctrlKey, props.altKey, props.shiftKey, props.metaKey,
props.button, props.relatedTarget
);
}
// make the event pass instanceof checks
e.__proto__ = ol.pointer.PointerEvent.prototype;
// define the buttons property according to DOM Level 3 spec
if (!ol.pointer.PointerEvent.HAS_BUTTONS) {
// IE 10 has buttons on MouseEvent.prototype as a getter w/o any setting
// mechanism
Object.defineProperty(e, 'buttons',
{get: function() { return buttons; }, enumerable: true});
}
// Spec requires that pointers without pressure specified use 0.5 for down
// state and 0 for up state.
var pressure = 0;
if (opt_inDict.pressure) {
pressure = opt_inDict.pressure;
} else {
pressure = buttons ? 0.5 : 0;
}
// define the properties of the PointerEvent interface
Object.defineProperties(e, {
pointerId: { value: opt_inDict.pointerId || 0, enumerable: true },
width: { value: opt_inDict.width || 0, enumerable: true },
height: { value: opt_inDict.height || 0, enumerable: true },
pressure: { value: pressure, enumerable: true },
tiltX: { value: opt_inDict.tiltX || 0, enumerable: true },
tiltY: { value: opt_inDict.tiltY || 0, enumerable: true },
pointerType: { value: opt_inDict.pointerType || '', enumerable: true },
hwTimestamp: { value: opt_inDict.hwTimestamp || 0, enumerable: true },
isPrimary: { value: opt_inDict.isPrimary || false, enumerable: true }
});
return e;
};
// PointerEvent extends MouseEvent
ol.pointer.PointerEvent.prototype = Object.create(MouseEvent.prototype);
// test for DOM Level 4 Events
/**
* Does the browser support the `MouseEvent` type?
* @type {boolean}
*/
ol.pointer.PointerEvent.NEW_MOUSE_EVENT = false;
/**
* Is the `buttons` property supported?
* @type {boolean}
*/
ol.pointer.PointerEvent.HAS_BUTTONS = false;
/**
* Checks if the `MouseEvent` type is supported.
*/
ol.pointer.PointerEvent.checkNewMouseEvent = function() {
try {
var ev = ol.pointer.PointerEvent.createMouseEvent('click', {buttons: 1});
ol.pointer.PointerEvent.NEW_MOUSE_EVENT = true;
ol.pointer.PointerEvent.HAS_BUTTONS = ev.buttons === 1;
} catch (e) {
}
};
ol.pointer.PointerEvent.checkNewMouseEvent();
/**
* Warning is suppressed because Closure thinks MouseEvent
* has no arguments.
* @param {string} inType The type of the event to create.
* @param {Object} inDict An dictionary of initial event properties.
* @return {MouseEvent}
* @suppress {checkTypes}
*/
ol.pointer.PointerEvent.createMouseEvent = function(inType, inDict) {
return new MouseEvent(inType, inDict);
};
/**
* List of properties to copy when creating an event.
* @type {Array.<string>}
*/
ol.pointer.PointerEvent.MOUSE_PROPS = [
'bubbles',
'cancelable',
'view',
'detail',
'screenX',
'screenY',
'clientX',
'clientY',
'ctrlKey',
'altKey',
'shiftKey',
'metaKey',
'button',
'relatedTarget'
];
/**
* List of default values when creating an event.
*/
ol.pointer.PointerEvent.MOUSE_DEFAULTS = [
false,
false,
null,
null,
0,
0,
0,
0,
false,
false,
false,
false,
0,
null
];