egroupware_official/api/js/jsapi/egw_ready.js

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/**
* EGroupware clientside API object
*
* @license http://opensource.org/licenses/gpl-license.php GPL - GNU General Public License
* @package etemplate
* @subpackage api
* @link http://www.egroupware.org
* @author Andreas Stöckel (as AT stylite.de)
* @version $Id$
*/
/*egw:uses
egw_core;
egw_utils;
egw_debug;
*/
/**
* @augments Class
* @param {string} _app application name object is instanciated for
* @param {object} _wnd window object is instanciated for
*/
egw.extend('ready', egw.MODULE_WND_LOCAL, function(_app, _wnd)
{
"use strict";
var egw = this;
var registeredCallbacks = [];
var registeredProgress = [];
var readyPending = {'readyEvent': true};
var readyPendingCnt = 1;
var readyDoneCnt = 0;
var isReady = false;
function doReadyWaitFor() {
if (!isReady)
{
var uid = egw.uid();
readyPending[uid] = true;
readyPendingCnt++;
readyProgressChange();
return uid;
}
this.debug('warning', 'ready has already been called!');
return null;
}
function doReadyDone(_token) {
if (typeof readyPending[_token] !== 'undefined')
{
delete readyPending[_token];
readyPendingCnt--;
readyDoneCnt++;
readyProgressChange();
testCallReady();
}
}
function readyProgressChange()
{
// Call all registered progress callbacks
for (var i = 0; i < registeredProgress.length; i++)
{
registeredProgress[i].callback.call(
registeredProgress[i].context,
readyDoneCnt,
readyPendingCnt
);
}
egw.debug('log', 'Ready events, processed %s/%s', readyDoneCnt,
readyPendingCnt + readyDoneCnt);
}
function readyEventHandler() {
doReadyDone('readyEvent');
}
function testCallReady()
{
// Check whether no further event is pending
if (readyPendingCnt <= 1 && !isReady)
{
// If exactly one event is pending and that one is not the ready
// event, abort
if (readyPendingCnt === 1 && !readyPending['readyEvent'])
{
return;
}
// Set "isReady" to true, if readyPendingCnt is zero
var isReady = readyPendingCnt === 0;
// Call all registered callbacks
for (var i = registeredCallbacks.length - 1; i >= 0; i--)
{
if (registeredCallbacks[i].before || readyPendingCnt === 0)
{
registeredCallbacks[i].callback.call(
registeredCallbacks[i].context
);
// Delete the callback from the list
registeredCallbacks.splice(i, 1);
}
}
}
}
// Register the event handler for "ready" (code adapted from jQuery)
// Mozilla, Opera and webkit nightlies currently support this event
if (_wnd.document.addEventListener) {
// Use the handy event callback
_wnd.document.addEventListener("DOMContentLoaded", readyEventHandler, false);
// A fallback to window.onload, that will always work
_wnd.addEventListener("load", readyEventHandler, false);
// If IE event model is used
} else if (_wnd.document.attachEvent) {
// ensure firing before onload,
// maybe late but safe also for iframes
_wnd.document.attachEvent("onreadystatechange", readyEventHandler);
// A fallback to window.onload, that will always work
_wnd.attachEvent("onload", readyEventHandler);
}
return {
/**
* The readyWaitFor function can be used to register an event, that has
* to be marked as "done" before the ready function will call its
* registered callbacks. The function returns an id that has to be
* passed to the "readDone" function once
*
* @memberOf egw
*/
readyWaitFor: function() {
return doReadyWaitFor();
},
/**
* The readyDone function can be used to mark a event token as
* previously requested by "readyWaitFor" as done.
*
* @param _token is the token which has now been processed.
*/
readyDone: function(_token) {
doReadyDone(_token);
},
/**
* The ready function can be used to register a function that will be
* called, when the window is completely loaded. All ready handlers will
* be called exactly once. If the ready handler has already been called,
* the given function will be called defered using setTimeout.
*
* @param _callback is the function which will be called when the page
* is ready. No parameters will be passed.
* @param _context is the context in which the callback function should
* get called.
* @param _beforeDOMContentLoaded specifies, whether the callback should
* get called, before the DOMContentLoaded event has been fired.
*/
ready: function(_callback, _context, _beforeDOMContentLoaded) {
if (!isReady)
{
registeredCallbacks.push({
'callback': _callback,
'context': _context ? _context : null,
'before': _beforeDOMContentLoaded ? true : false
});
}
else
{
setTimeout(function() {
_callback.call(_context);
}, 1);
}
},
/**
* The readyProgress function can be used to register a function that
* will be called whenever a ready event is done or registered.
*
* @param _callback is the function which will be called when the
* progress changes.
* @param _context is the context in which the callback function which
* should get called.
*/
readyProgress: function(_callback, _context) {
if (!isReady)
{
registeredProgress.unshift({
'callback': _callback,
'context': _context ? _context : null
});
}
else
{
this.debug('warning', 'ready has already been called!');
}
},
/**
* Returns whether the ready events have already been called.
*/
isReady: function() {
return isReady;
}
};
});