source: Dev/trunk/src/client/dojox/app/utils/constraints.js

define(["dojo/_base/array"], function(arr){
        var constraints = [];
        return {
                getSelectedChild: function(view, constraint){
                        // summary:
                        //              get current selected child according to the constraint
                        //
                        // view: View
                        //              the View to get the child from
                        // constraint: Object
                        //              tbe constraint object
                        //
                        // returns:
                        //              the selected child view for this constraint
                        var type = typeof(constraint);
                        var hash = (type == "string" || type == "number") ? constraint : constraint.__hash;
                        return (view && view.selectedChildren && view.selectedChildren[hash]) ?
                                view.selectedChildren[hash] : null;
                },

                setSelectedChild: function(view, constraint, child){
                        // summary:
                        //              set current selected child according to the constraint
                        //
                        // view: View
                        //              the View to set the selected child to
                        // constraint: Object
                        //              tbe constraint object
                        // child: View
                        //              the child to select
                        var type = typeof(constraint);
                        var hash = (type == "string" || type == "number") ? constraint : constraint.__hash;
                        view.selectedChildren[hash] = child;
                },


                getAllSelectedChildren: function(view, selChildren){
                        // summary:
                        //              get current all selected children for this view and it's selected subviews
                        //
                        // view: View
                        //              the View to get the child from
                        //
                        // selChildren: Array
                        //              the Array of the subChildren found
                        //
                        // returns:
                        //              selChildren array of all of the selected child views
                        //
                        selChildren = selChildren || [];
                        if(view && view.selectedChildren){
                                for(var hash in view.selectedChildren){
                                        if(view.selectedChildren[hash]){
                                                var subChild = view.selectedChildren[hash];
                                                selChildren.push(subChild);
                                                this.getAllSelectedChildren(subChild, selChildren);
                                        }
                                }
                        }
                        return selChildren;
                },

                register: function(constraint){
                        // if the constraint has already been registered we don't care about it...
                        var type = typeof(constraint);
                        if(!constraint.__hash && type != "string" && type != "number"){
                                var match = null;
                                arr.some(constraints, function(item){
                                        var ok = true;
                                        for(var prop in item){
                                                if(prop.charAt(0) !== "_"){//skip the private properties
                                                        if(item[prop] != constraint[prop]){
                                                                ok = false;
                                                                break;
                                                        }
                                                }
                                        }
                                        if(ok == true){
                                                match = item;
                                        }
                                        return ok;
                                });
                                if(match){
                                        constraint.__hash = match.__hash;
                                }else{
                                        // create a new "hash"
                                        var hash = "";
                                        for(var prop in constraint){
                                                if(prop.charAt(0) !== "_"){
                                                        hash += constraint[prop];
                                                }
                                        }
                                        constraint.__hash = hash;
                                        constraints.push(constraint);
                                }
                        }
                }
        };
});