/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* File: background.js *
* Classes: n/a *
* Author: Keith Borgmann *
* Date: 2009-05-14 *
* Version: 1.1.1 *
* *
* Update Notes: *
* background.js now supports mutliple "layers" of backgrounds. *
*** ALL FOLLOWING COMMENTS NEED TO BE UPDATED. ***
* Description: *
* Creates a transparent 'background' that disables access to most of the *
* page. All objects at z-index:2; or greater will still be accessible. *
//TODO: update this note
* *
* Methods List: *
* createBackground(); //only needs to be called once (do it onload) *
* activateBackground(fn); //fn - function called if the layer is clicked *
* deactivateBackground(); //Close the background & calls fn *
* *
* Dependencies: *
* compatibility.js(1.1.0), background.css, IMG_BACKGROUND (see below) *
* *
* Notes: *
* Only supports one background at a time, and always at z-index:1; *
Works best with
//TODO: update this note
* *
* BEFORE USING: *
* Copy Files: *
* ../common/js/background.js *
* ../common/css/background.css *
* ../common/img/transparent.gif *
//TODO: update this note
* *
* Add to html/jsp file: *
* *
* *
* *
* Add to window.onload: *
* createBackground(); *
//TODO: update this note
* *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
//TODO: validate full compatibility for mozilla & ns
//CONSTANTS//////
var BACKGROUNDID = "_div_background_v100_"; //unique id for the div
var BACKGROUND_CLASS = "divBackground"; //class name (see background.css)
var IMG_BACKGROUND = "../common/img/transparent.gif"; //a transparent gif.
/////////////////////////////////////////////////////////////
//Class: ActiveBackground
//Desc: Holds info about a layered instance of a background.
// Used Internally by the static methods.
//
//Constructor: ActiveBackground
//Desc: Create a new ActiveBackground instance, and activates it.
//Params: strFunction - onclick/oncomplete code.
function ActiveBackground(strFunction) {
//Instance Members
this.functionDone = strFunction;
this.layer = ActiveBackground.layer+1;
ActiveBackground.float();
//Set global reference.
ActiveBackground.layers[this.layer-1] = this;
//Prepare onclick
var back = ActiveBackground.background;
eval("back.onclick = function() { "+this.functionDone+"; return false;}");
}
//Method: deactivate
//Desc: Deactivate a layered background
//Params: blnCallDone - if true, call the onclick/oncomplete code.
ActiveBackground.prototype.deactivate = function(blnCallDone) {
if (ActiveBackground.layer==this.layer) {
ActiveBackground.sink();
if (blnCallDone)
eval(this.functionDone);
}
var currentLayer = this.layer;
//clear the global reference
ActiveBackground.layers[currentLayer-1] = null;
currentLayer--;
if (currentLayer > 0) {
var back = ActiveBackground.background;
var bg = ActiveBackground.layers[currentLayer-1];
//Prepare new onclick
eval("back.onclick = function() { "+bg.functionDone+"; return false;}");
}
}
//Static method: Sink background down one layer
ActiveBackground.sink = function() {
if (ActiveBackground.layer!=0) {
var back = ActiveBackground.background;
ActiveBackground.layer--;
if (ActiveBackground.layer==0)
back.style.display = "none";
else
back.style.zIndex = ActiveBackground.layer;
} else {
alert("Cannot sink background: already at level 0");
}
};
//Static method: Float background up one layer
ActiveBackground.float = function() {
var back = ActiveBackground.background;
ActiveBackground.layer++;
back.style.zIndex = ActiveBackground.layer;
if (ActiveBackground.layer==1)
back.style.display = "";
};
//Static method: Move the div in front of the background
ActiveBackground.toForeground = function(div) {
div.style.zIndex = ActiveBackground.layer+1;
}
//End of Class
/////////////////////////////////////////////////////////////
//Global Functions/////////////////////////////////////////////////////////////
//TODO: move this to util.js
function createDiv(strDivName, objPreceedingChild) {
var dv = document.createElement('div');
if (strDivName!=null)
dv.setAttribute('id', strDivName);
insertElement(dv, objPreceedingChild);
return dv;
}
//Inserts an html element to the document body, or after the specified element
//TODO: move this to util.js
function insertElement(objInsert, objPreceedingChild) {
if (objPreceedingChild==null)
document.body.appendChild(objInsert);
else {
var parent = objPreceedingChild.parentNode;
var next = objPreceedingChild.nextSibling;
if (next==null)
parent.appendChild(objInsert);
else
parent.insertBefore(objInsert, next);
}
}
///////////////////////////////////////////////////////////////////////////////
//Creates a 'background' that encompases the entire screen
//Only needs to be called once, but multiple calls to not create errors.
//Optionally set a new transparent image file.
function createBackground(img) {
if (img)
IMG_BACKGROUND = img;
if( element(BACKGROUNDID)==null ) {
var back = createDiv(BACKGROUNDID);
back.className = BACKGROUND_CLASS;
back.style.display = "none";
back.functionDone = "";
back.style.background = "url("+IMG_BACKGROUND+") 0 0 repeat";
if (typeof(ActiveBackground.layer)=="undefined") {
ActiveBackground.layers = new Array();
ActiveBackground.layer = 0;
ActiveBackground.background = back;
}
}
}
//returns a reference to the background div
function activateBackground(strFunction) {
var back = element(BACKGROUNDID);
if( back==null ) {
createBackground(); //try to create the background
back = ActiveBackground.background;
}
resizeBackground();
var current = new ActiveBackground(strFunction); //new instance
return back;
}
//Remove the current-layer background (drop one);
function deactivateBackground(blnCallDone) {
try {
var layer = ActiveBackground.layer;
ActiveBackground.layers[layer-1].deactivate(blnCallDone);
} catch(e) {
//alert("Error: "+e.message);
}
}
//resize the background.
function resizeBackground(toZero) {
var back = ActiveBackground.background;
if (toZero) {
back.style.width = "0px";
back.style.height = "0px";
} else {
var size = getBrowserSize();
if (document.viewport) {
var width = Math.max( document.viewport.getWidth(), size.width);
var height = Math.max( document.viewport.getHeight(), size.height);
} else {
var width = size.width;
var height = size.height;
}
back.style.width = width+"px";
back.style.height = height+"px";
//alert("Doc: "+dw+"x"+dh+"\nBrows: "+ size.width+"x"+size.height);
}
}
//////////////////////////////////////////////////////////////////
//Code for onDemand loading. Must be the last lines in the file.
if ( typeof(onDemandJSLoaded)=="undefined") var onDemandJSLoaded = new Object();
onDemandJSLoaded["background.js"] = true;
if ( typeof(onDemandCallback)=="function" ) onDemandCallback();