source: Dev/trunk/src/client/dojox/app/tests/layoutApp2/controllers/UnloadViewController.js

define(["dojo/_base/lang","dojo/_base/declare", "dojo/Deferred", "dojo/_base/array", "dojo/dom-construct", "dijit/registry", "dojox/app/Controller"],
        function(lang, declare, Deferred, array, domConstruct, registry, Controller){
        // module:
        //              dojox/app/tests/layoutApp2/controllers/UnloadViewController
        // summary:
        //              Used to Unload Views when they are no longer needed
        //              Bind "unload-view" event on dojox/app application instance.
        //              Do transition from one view to another view.

        return declare("dojox/app/tests/layoutApp2/controllers/UnloadViewController", Controller, {

                constructor: function(app){
                        this.app = app;
                        // summary:
                        //              bind "app-transition" event on application instance.
                        //
                        // app:
                        //              dojox/app application instance.
                        // events:
                        //              {event : handler}
                        this.events = {
                                "unload-view": this.unloadView
                        };
                },

                unloadView: function(event){
                        // summary:
                        //              Response to dojox/app "unload-view" event.
                        //              If a view has children loaded the view and any children of the child will be unloaded.
                        //
                        // example:
                        //              Use trigger() to trigger "unload-view" event, and this function will response the event. For example:
                        //              |       this.trigger("unload-view", {"parent":parent, "view":view, "callback":function(){...}});
                        //
                        // event: Object
                        //              unloadView event parameter. It should be like this: {"parent":parent, "view":view, "callback":function(){...}}

                        var parent = event.parent || this.app;
                        var view = event.view || "";
                        var viewId = view.id;

                        if(!parent || !view || !viewId){
                                console.warn("unload-view event for view with no parent or with an invalid view with view = ", view);
                                return;
                        }

                        if(parent.selectedChildren[viewId]){
                                console.warn("unload-view event for a view which is still in use so it can not be unloaded for view id = " + viewId + "'.");
                                return;
                        }

                        if(!parent.children[viewId]){
                                console.warn("unload-view event for a view which was not found in parent.children[viewId] for viewId = " + viewId + "'.");
                                return;
                        }

                        this.unloadChild(parent, view);

                        // call Load event callback
                        if(event.callback){
                                event.callback();
                        }
                },

                unloadChild: function(parent, viewToUnload){
                        // summary:
                        //              Unload the view, and all of its child views recursively.
                        //              Destroy all children, destroy all widgets, destroy the domNode, remove the view from the parent.children,
                        //              then destroy the view.
                        //
                        // parent: Object
                        //              parent of this view.
                        // viewToUnload: Object
                        //              the view to be unloaded.

                        for(var child in viewToUnload.children){
                                this.unloadChild(viewToUnload, child);  // unload children then unload the view itself
                        }
                        if(viewToUnload.domNode){
                                // destroy all widgets, then destroy the domNode, then destroy the view.
                                var widList = registry.findWidgets(viewToUnload.domNode);
                                for(var wid in widList){
                                        widList[wid].destroyRecursive();
                                }
                                domConstruct.destroy(viewToUnload.domNode);
                        }

                        delete parent.children[viewToUnload.id]; // remove it from the parents children
                        if(viewToUnload.destroy){
                                viewToUnload.destroy(); // call destroy for the view.
                        }
                }
        });
});