@qooxdoo/framework
Version:
The JS Framework for Coders
203 lines (164 loc) • 5.42 kB
JavaScript
/* ************************************************************************
qooxdoo - the new era of web development
http://qooxdoo.org
Copyright:
2007-2008 1&1 Internet AG, Germany, http://www.1und1.de
License:
MIT: https://opensource.org/licenses/MIT
See the LICENSE file in the project's top-level directory for details.
Authors:
* Sebastian Werner (wpbasti)
************************************************************************ */
/**
* This class supports <code>appear</code> and <code>disappear</code> events
* on DOM level.
*
* NOTE: Instances of this class must be disposed of after use
*
*/
qx.Class.define("qx.event.handler.Appear", {
extend: qx.core.Object,
implement: [qx.event.IEventHandler, qx.core.IDisposable],
/*
*****************************************************************************
CONSTRUCTOR
*****************************************************************************
*/
/**
* Create a new instance
*
* @param manager {qx.event.Manager} Event manager for the window to use
*/
construct(manager) {
super();
this.__manager = manager;
this.__targets = {};
// Register
qx.event.handler.Appear.__instances[this.toHashCode()] = this;
},
/*
*****************************************************************************
STATICS
*****************************************************************************
*/
statics: {
/** @type {Integer} Priority of this handler */
PRIORITY: qx.event.Registration.PRIORITY_NORMAL,
/** @type {Map} Supported event types */
SUPPORTED_TYPES: {
appear: true,
disappear: true
},
/** @type {Integer} Which target check to use */
TARGET_CHECK: qx.event.IEventHandler.TARGET_DOMNODE,
/** @type {Integer} Whether the method "canHandleEvent" must be called */
IGNORE_CAN_HANDLE: true,
/** @type {Map} Stores all appear manager instances */
__instances: {},
/**
* Refreshes all appear handlers. Useful after massive DOM manipulations e.g.
* through qx.html.Element.
*
*/
refresh() {
var all = this.__instances;
for (var hash in all) {
all[hash].refresh();
}
}
},
/*
*****************************************************************************
MEMBERS
*****************************************************************************
*/
members: {
__manager: null,
__targets: null,
/*
---------------------------------------------------------------------------
EVENT HANDLER INTERFACE
---------------------------------------------------------------------------
*/
// interface implementation
canHandleEvent(target, type) {},
// interface implementation
registerEvent(target, type, capture) {
var hash = qx.core.ObjectRegistry.toHashCode(target) + type;
var targets = this.__targets;
if (targets && !targets[hash]) {
targets[hash] = target;
target.$$displayed = target.offsetWidth > 0;
}
},
// interface implementation
unregisterEvent(target, type, capture) {
var hash = qx.core.ObjectRegistry.toHashCode(target) + type;
var targets = this.__targets;
if (!targets) {
return;
}
if (targets[hash]) {
delete targets[hash];
}
},
/*
---------------------------------------------------------------------------
USER ACCESS
---------------------------------------------------------------------------
*/
/**
* This method should be called by all DOM tree modifying routines
* to check the registered nodes for changes.
*
* @return {qx.Promise?} a promise, if one or more of the event handlers returned one
*/
refresh() {
var targets = this.__targets;
var legacyIe =
qx.core.Environment.get("engine.name") == "mshtml" &&
qx.core.Environment.get("browser.documentmode") < 9;
var tracker = {};
var self = this;
Object.keys(targets).forEach(function (hash) {
var elem = targets[hash];
if (elem === undefined) {
return;
}
qx.event.Utils.then(tracker, function () {
var displayed = elem.offsetWidth > 0;
if (!displayed && legacyIe) {
// force recalculation in IE 8. See bug #7872
displayed = elem.offsetWidth > 0;
}
if (!!elem.$$displayed !== displayed) {
elem.$$displayed = displayed;
var evt = qx.event.Registration.createEvent(
displayed ? "appear" : "disappear"
);
return self.__manager.dispatchEvent(elem, evt);
}
});
});
return tracker.promise;
}
},
/*
*****************************************************************************
DESTRUCTOR
*****************************************************************************
*/
destruct() {
this.__manager = this.__targets = null;
// Deregister
delete qx.event.handler.Appear.__instances[this.toHashCode()];
},
/*
*****************************************************************************
DEFER
*****************************************************************************
*/
defer(statics) {
qx.event.Registration.addHandler(statics);
}
});