source: Dev/trunk/src/client/dijit/BackgroundIframe.js @ 532

define([
        "require",                      // require.toUrl
        "./main",       // to export dijit.BackgroundIframe
        "dojo/_base/config",
        "dojo/dom-construct", // domConstruct.create
        "dojo/dom-style", // domStyle.set
        "dojo/_base/lang", // lang.extend lang.hitch
        "dojo/on",
        "dojo/sniff" // has("ie"), has("mozilla"), has("quirks")
], function(require, dijit, config, domConstruct, domStyle, lang, on, has){

        // module:
        //              dijit/BackgroundIFrame

        // Flag for whether to create background iframe behind popups like Menus and Dialog.
        // A background iframe is useful to prevent problems with popups appearing behind applets/pdf files,
        // and is also useful on older versions of IE (IE6 and IE7) to prevent the "bleed through select" problem.
        // TODO: For 2.0, make this false by default.  Also, possibly move definition to has.js so that this module can be
        // conditionally required via  dojo/has!bgIfame?dijit/BackgroundIframe
        has.add("config-bgIframe", !has("touch"));

        // TODO: remove _frames, it isn't being used much, since popups never release their
        // iframes (see [22236])
        var _frames = new function(){
                // summary:
                //              cache of iframes

                var queue = [];

                this.pop = function(){
                        var iframe;
                        if(queue.length){
                                iframe = queue.pop();
                                iframe.style.display="";
                        }else{
                                // transparency needed for DialogUnderlay and for tooltips on IE (to see screen near connector)
                                if(has("ie") < 9){
                                        var burl = config["dojoBlankHtmlUrl"] || require.toUrl("dojo/resources/blank.html") || "javascript:\"\"";
                                        var html="<iframe src='" + burl + "' role='presentation'"
                                                + " style='position: absolute; left: 0px; top: 0px;"
                                                + "z-index: -1; filter:Alpha(Opacity=\"0\");'>";
                                        iframe = document.createElement(html);
                                }else{
                                        iframe = domConstruct.create("iframe");
                                        iframe.src = 'javascript:""';
                                        iframe.className = "dijitBackgroundIframe";
                                        iframe.setAttribute("role", "presentation");
                                        domStyle.set(iframe, "opacity", 0.1);
                                }
                                iframe.tabIndex = -1; // Magic to prevent iframe from getting focus on tab keypress - as style didn't work.
                        }
                        return iframe;
                };

                this.push = function(iframe){
                        iframe.style.display="none";
                        queue.push(iframe);
                }
        }();


        dijit.BackgroundIframe = function(/*DomNode*/ node){
                // summary:
                //              For IE/FF z-index shenanigans. id attribute is required.
                //
                // description:
                //              new dijit.BackgroundIframe(node).
                //
                //              Makes a background iframe as a child of node, that fills
                //              area (and position) of node

                if(!node.id){ throw new Error("no id"); }
                if(has("config-bgIframe")){
                        var iframe = (this.iframe = _frames.pop());
                        node.appendChild(iframe);
                        if(has("ie")<7 || has("quirks")){
                                this.resize(node);
                                this._conn = on(node, 'resize', lang.hitch(this, "resize", node));
                        }else{
                                domStyle.set(iframe, {
                                        width: '100%',
                                        height: '100%'
                                });
                        }
                }
        };

        lang.extend(dijit.BackgroundIframe, {
                resize: function(node){
                        // summary:
                        //              Resize the iframe so it's the same size as node.
                        //              Needed on IE6 and IE/quirks because height:100% doesn't work right.
                        if(this.iframe){
                                domStyle.set(this.iframe, {
                                        width: node.offsetWidth + 'px',
                                        height: node.offsetHeight + 'px'
                                });
                        }
                },
                destroy: function(){
                        // summary:
                        //              destroy the iframe
                        if(this._conn){
                                this._conn.remove();
                                this._conn = null;
                        }
                        if(this.iframe){
                                _frames.push(this.iframe);
                                delete this.iframe;
                        }
                }
        });

        return dijit.BackgroundIframe;
});