source: Dev/trunk/src/client/dijit/_KeyNavContainer.js

define([
        "dojo/_base/array", // array.forEach
        "dojo/_base/declare", // declare
        "dojo/dom-attr", // domAttr.set
        "dojo/_base/kernel", // kernel.deprecated
        "dojo/keys", // keys.END keys.HOME
        "dojo/_base/lang", // lang.hitch
        "./registry",
        "./_Container",
        "./_FocusMixin",
        "./_KeyNavMixin"
], function(array, declare, domAttr, kernel, keys, lang, registry, _Container, _FocusMixin, _KeyNavMixin){


        // module:
        //              dijit/_KeyNavContainer

        return declare("dijit._KeyNavContainer", [_FocusMixin, _KeyNavMixin, _Container], {
                // summary:
                //              A _Container with keyboard navigation of its children.
                // description:
                //              Provides normalized keyboard and focusing code for Container widgets.
                //              To use this mixin, call connectKeyNavHandlers() in postCreate().
                //              Also, child widgets must implement a focus() method.

                connectKeyNavHandlers: function(/*keys[]*/ prevKeyCodes, /*keys[]*/ nextKeyCodes){
                        // summary:
                        //              Deprecated.  You can call this in postCreate() to attach the keyboard handlers to the container,
                        //              but the preferred method is to override _onLeftArrow() and _onRightArrow(), or
                        //              _onUpArrow() and _onDownArrow(), to call focusPrev() and focusNext().
                        // prevKeyCodes: keys[]
                        //              Key codes for navigating to the previous child.
                        // nextKeyCodes: keys[]
                        //              Key codes for navigating to the next child.
                        // tags:
                        //              protected

                        // TODO: remove for 2.0, and make subclasses override _onLeftArrow, _onRightArrow etc. instead.

                        var keyCodes = (this._keyNavCodes = {});
                        var prev = lang.hitch(this, "focusPrev");
                        var next = lang.hitch(this, "focusNext");
                        array.forEach(prevKeyCodes, function(code){
                                keyCodes[code] = prev;
                        });
                        array.forEach(nextKeyCodes, function(code){
                                keyCodes[code] = next;
                        });
                        keyCodes[keys.HOME] = lang.hitch(this, "focusFirstChild");
                        keyCodes[keys.END] = lang.hitch(this, "focusLastChild");
                },

                startupKeyNavChildren: function(){
                        kernel.deprecated("startupKeyNavChildren() call no longer needed", "", "2.0");
                },

                startup: function(){
                        this.inherited(arguments);
                        array.forEach(this.getChildren(), lang.hitch(this, "_startupChild"));
                },

                addChild: function(/*dijit/_WidgetBase*/ widget, /*int?*/ insertIndex){
                        this.inherited(arguments);
                        this._startupChild(widget);
                },

                _startupChild: function(/*dijit/_WidgetBase*/ widget){
                        // summary:
                        //              Setup for each child widget.
                        // description:
                        //              Sets tabIndex=-1 on each child, so that the tab key will
                        //              leave the container rather than visiting each child.
                        //
                        //              Note: if you add children by a different method than addChild(), then need to call this manually
                        //              or at least make sure the child's tabIndex is -1.
                        //
                        //              Note: see also _LayoutWidget.setupChild(), which is also called for each child widget.
                        // tags:
                        //              private

                        widget.set("tabIndex", "-1");
                },

                _getFirst: function(){
                        // summary:
                        //              Returns the first child.
                        // tags:
                        //              abstract extension
                        var children = this.getChildren();
                        return children.length ? children[0] : null;
                },

                _getLast: function(){
                        // summary:
                        //              Returns the last descendant.
                        // tags:
                        //              abstract extension
                        var children = this.getChildren();
                        return children.length ? children[children.length - 1] : null;
                },

                focusNext: function(){
                        // summary:
                        //              Focus the next widget
                        // tags:
                        //              protected
                        this.focusChild(this._getNextFocusableChild(this.focusedChild, 1));
                },

                focusPrev: function(){
                        // summary:
                        //              Focus the last focusable node in the previous widget
                        //              (ex: go to the ComboButton icon section rather than button section)
                        // tags:
                        //              protected
                        this.focusChild(this._getNextFocusableChild(this.focusedChild, -1), true);
                },

                childSelector: function(/*DOMNode*/ node){
                        // Implement _KeyNavMixin.childSelector, to identify focusable child nodes.
                        // If we allowed a dojo/query dependency from this module this could more simply be a string "> *"
                        // instead of this function.

                        var node = registry.byNode(node);
                        return node && node.getParent() == this;
                }
        });
});