GST work in progress.

common/lib/xmodule/xmodule/js/src/graphical_slider_tool/graph.js

@@ -19,22 +19,20 @@ define('Graph', ['logme'], function (logme) {
         plotDiv.width(300);
         plotDiv.height(300);
 
-        plotDiv.bind('update_plot', function (event, forGstId) {
-            if (forGstId !== gstId) {
-                logme('update_plot event not for current ID');
-            }
-
-            logme('redrawing plot');
-
-            generateData();
-            updatePlot();
-        });
+        state.bindUpdatePlotEvent(plotDiv, onUpdatePlot);
 
         generateData();
         updatePlot();
 
         return;
 
+        function onUpdatePlot(event) {
+            logme('redrawing plot');
+
+            generateData();
+            updatePlot();
+        }
+
         function generateData() {
             var a, b, c1;
 

common/lib/xmodule/xmodule/js/src/graphical_slider_tool/state.js

@@ -18,7 +18,7 @@ define('State', ['logme'], function (logme) {
      *
      */
     function State(gstId, config) {
-        var constants, c1;
+        var constants, c1, plotDiv;
 
         constants = {};
 
@@ -62,9 +62,16 @@ define('State', ['logme'], function (logme) {
         // it's private properties.
         return {
             'getConstValue': getConstValue,
-            'setConstValue': setConstValue
+            'setConstValue': setConstValue,
+            'bindUpdatePlotEvent': bindUpdatePlotEvent
         };
 
+        function bindUpdatePlotEvent(newPlotDiv, callback) {
+            plotDiv = newPlotDiv;
+
+            plotDiv.bind('update_plot', callback);
+        }
+
         function getConstValue(constName) {
             if (constants.hasOwnProperty(constName) === false) {
                 // If the name of the constant is not tracked by state, return an
@@ -76,8 +83,6 @@ define('State', ['logme'], function (logme) {
         }
 
         function setConstValue(constName, constValue) {
-            var plotDiv;
-
             if (constants.hasOwnProperty(constName) === false) {
                 // If the name of the constant is not tracked by state, return an
                 // 'undefined' value.
@@ -93,10 +98,8 @@ define('State', ['logme'], function (logme) {
 
             logme('From setConstValue: new value for "' + constName + '" is ' + constValue);
 
-            plotDiv = $('#' + gstId + '_plot');
-
-            if (plotDiv.length === 1) {
-                plotDiv.trigger('update_plot', [gstId]);
+            if (plotDiv !== undefined) {
+                plotDiv.trigger('update_plot');
             }
         }