rwt.html.ImageManager.js Maven / Gradle / Ivy
/*******************************************************************************
* Copyright: 2004, 2012 1&1 Internet AG, Germany, http://www.1und1.de,
* and EclipseSource
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 which accompanies this
* distribution, and is available at http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* 1&1 Internet AG and others - original API and implementation
* EclipseSource - adaptation for the Eclipse Rich Ajax Platform
******************************************************************************/
/** This singleton manage stuff around image handling. */
rwt.qx.Class.define("rwt.html.ImageManager",
{
type : "singleton",
extend : rwt.qx.Target,
/*
*****************************************************************************
CONSTRUCTOR
*****************************************************************************
*/
construct : function()
{
this.base(arguments);
this.__visible = {};
this.__all = {};
},
/*
*****************************************************************************
MEMBERS
*****************************************************************************
*/
members :
{
/**
* Register an image.
* Gives the application the possibility to preload images.
*
* @type member
* @param source {String} The incoming (unresolved) URL.
* @return {void}
*/
add : function(source)
{
var data = this.__all;
if (data[source] === undefined) {
data[source] = 1;
} else {
data[source]++;
}
},
/**
* Register an image.
* Gives the application the possibility to preload images.
*
* @type member
* @param source {String} The incoming (unresolved) URL.
* @return {void}
*/
remove : function(source)
{
var data = this.__all;
if (data[source] !== undefined) {
data[source]--;
}
if (data[source] <= 0) {
delete data[source];
}
},
/**
* Register an visible image.
* Gives the application the possibility to preload visible images.
*
* @type member
* @param source {String} The incoming (unresolved) URL.
* @return {void}
*/
show : function(source)
{
var data = this.__visible;
if (data[source] === undefined) {
data[source] = 1;
} else {
data[source]++;
}
},
/**
* Register an image and reduce the visible counter
* Warning: Only use after using show() before
*
* @type member
* @param source {String} The incoming (unresolved) URL.
* @return {void}
*/
hide : function(source)
{
var data = this.__visible;
if (data[source] !== undefined) {
data[source]--;
}
if (data[source]<=0) {
delete data[source];
}
},
/**
* Returns a map with the sources of all visible images
*
* @type member
* @return {Map} Map with sources of all visible images
*/
getVisibleImages : function()
{
var visible = this.__visible;
var list = {};
for (var source in visible)
{
if (visible[source] > 0) {
list[source] = true;
}
}
return list;
},
/**
* Returns a map with the sources of all hidden images
*
* @type member
* @return {Map} Map with sources of all hidden images
*/
getHiddenImages : function()
{
var visible = this.__visible;
var all = this.__all;
var list = {};
for (var source in all)
{
if (visible[source] === undefined) {
list[source] = true;
}
}
return list;
}
},
/*
*****************************************************************************
DESTRUCTOR
*****************************************************************************
*/
destruct : function() {
this._disposeFields("__all", "__visible");
}
});