source: Dev/branches/rest-dojo-ui/client/dojo/_base/unload.js @ 263

define(["./kernel", "./connect"], function(dojo, connect) {
        // module:
        //              dojo/unload
        // summary:
        //              This module contains the document and window unload detection API.

        var win = window;

        /*=====
                dojo.windowUnloaded = function(){
                        // summary:
                        //              signal fired by impending window destruction. You may use
                        //              dojo.addOnWindowUnload() to register a listener for this
                        //              event. NOTE: if you wish to dojo.connect() to this method
                        //              to perform page/application cleanup, be aware that this
                        //              event WILL NOT fire if no handler has been registered with
                        //              dojo.addOnWindowUnload. This behavior started in Dojo 1.3.
                        //              Previous versions always triggered dojo.windowUnloaded. See
                        //              dojo.addOnWindowUnload for more info.
                };
        =====*/

        dojo.addOnWindowUnload = function(/*Object?|Function?*/obj, /*String|Function?*/functionName){
                // summary:
                //              registers a function to be triggered when window.onunload
                //              fires.
                //      description:
                //              The first time that addOnWindowUnload is called Dojo
                //              will register a page listener to trigger your unload
                //              handler with. Note that registering these handlers may
                //              destory "fastback" page caching in browsers that support
                //              it. Be careful trying to modify the DOM or access
                //              JavaScript properties during this phase of page unloading:
                //              they may not always be available. Consider
                //              dojo.addOnUnload() if you need to modify the DOM or do
                //              heavy JavaScript work since it fires at the eqivalent of
                //              the page's "onbeforeunload" event.
                // example:
                //      | dojo.addOnWindowUnload(functionPointer)
                //      | dojo.addOnWindowUnload(object, "functionName");
                //      | dojo.addOnWindowUnload(object, function(){ /* ... */});

                if (!dojo.windowUnloaded) {
                        connect.connect(win, "unload", (dojo.windowUnloaded= function(){}));
                }
                connect.connect(win, "unload", obj, functionName);
        };

        dojo.addOnUnload = function(/*Object?|Function?*/obj, /*String|Function?*/functionName){
                // summary:
                //              registers a function to be triggered when the page unloads.
                //      description:
                //              The first time that addOnUnload is called Dojo will
                //              register a page listener to trigger your unload handler
                //              with.
                //
                //              In a browser enviroment, the functions will be triggered
                //              during the window.onbeforeunload event. Be careful of doing
                //              too much work in an unload handler. onbeforeunload can be
                //              triggered if a link to download a file is clicked, or if
                //              the link is a javascript: link. In these cases, the
                //              onbeforeunload event fires, but the document is not
                //              actually destroyed. So be careful about doing destructive
                //              operations in a dojo.addOnUnload callback.
                //
                //              Further note that calling dojo.addOnUnload will prevent
                //              browsers from using a "fast back" cache to make page
                //              loading via back button instantaneous.
                // example:
                //      | dojo.addOnUnload(functionPointer)
                //      | dojo.addOnUnload(object, "functionName")
                //      | dojo.addOnUnload(object, function(){ /* ... */});

                connect.connect(win, "beforeunload", obj, functionName);
        };

        return {
                addOnWindowUnload: dojo.addOnWindowUnload,
                addOnUnload: dojo.addOnUnload
        };
});