source: Dev/trunk/src/client/dijit/_editor/plugins/ToggleDir.js

define([
        "dojo/_base/declare", // declare
        "dojo/dom-style", // domStyle.getComputedStyle
        "dojo/_base/kernel", // kernel.experimental
        "dojo/_base/lang", // lang.hitch
        "dojo/on",
        "../_Plugin",
        "../../form/ToggleButton"
], function(declare, domStyle, kernel, lang, on, _Plugin, ToggleButton){

        // module:
        //              dijit/_editor/plugins/ToggleDir

        kernel.experimental("dijit._editor.plugins.ToggleDir");

        var ToggleDir = declare("dijit._editor.plugins.ToggleDir", _Plugin, {
                // summary:
                //              This plugin is used to toggle direction of the edited document,
                //              independent of what direction the whole page is.

                // Override _Plugin.useDefaultCommand: processing is done in this plugin
                // rather than by sending commands to the Editor
                useDefaultCommand: false,

                command: "toggleDir",

                // Override _Plugin.buttonClass to use a ToggleButton for this plugin rather than a vanilla Button
                buttonClass: ToggleButton,

                _initButton: function(){
                        // Override _Plugin._initButton() to setup handler for button click events.
                        this.inherited(arguments);
                        this.editor.onLoadDeferred.then(lang.hitch(this, function(){
                                var editDoc = this.editor.editorObject.contentWindow.document.documentElement;
                                //IE direction has to toggle on the body, not document itself.
                                //If you toggle just the document, things get very strange in the
                                //view.  But, the nice thing is this works for all supported browsers.
                                editDoc = editDoc.getElementsByTagName("body")[0];
                                var isLtr = domStyle.getComputedStyle(editDoc).direction == "ltr";
                                this.button.set("checked", !isLtr);
                                this.own(this.button.on("change", lang.hitch(this, "_setRtl")));
                        }));
                },

                updateState: function(){
                        // summary:
                        //              Over-ride for button state control for disabled to work.
                        this.button.set("disabled", this.get("disabled"));
                },

                _setRtl: function(rtl){
                        // summary:
                        //              Handler for button click events, to switch the text direction of the editor
                        var dir = "ltr";
                        if(rtl){
                                dir = "rtl";
                        }
                        var editDoc = this.editor.editorObject.contentWindow.document.documentElement;
                        editDoc = editDoc.getElementsByTagName("body")[0];
                        editDoc.dir/*html node*/ = dir;
                }
        });

        // Register this plugin.
        _Plugin.registry["toggleDir"] = function(){
                return new ToggleDir({command: "toggleDir"});
        };

        return ToggleDir;
});