handle 'back' as a separate menu option

Author: gfwilliams

modules/graphical_menu.js

@@ -3,7 +3,13 @@
 exports.list = function(g, items) {
   var options = items[""];
   var menuItems = Object.keys(items);
-  if (options) menuItems.splice(menuItems.indexOf(""),1);
+  if (options) {
+    menuItems.splice(menuItems.indexOf(""),1);
+    if (options.back) { // handle 'options.back'
+      items["< Back"] = options.back;
+      menuItems.unshift("< Back");
+    }
+  }
   if (!(options instanceof Object)) options = {};
   if (options.selected === undefined)
     options.selected = 0;

modules/graphical_menu.md

@@ -80,6 +80,7 @@ Each object is as follows:
 var menuinfo = {
   "" : {
     "title": "...", // optional, the menu's title
+    "back" : function() { } // optional - adds a menu item to go 'back' which calls this function
     "selected": 0, // optional, first selected menu item's index
     "fontHeight": 0, // optional, height of the font being used (default is 6)
     "y": 0, // optional, y offset of menu