prevent x-overflow of dragbar which might have occured when the editor

view is split on two screens

vispa/extensions/codeeditor/static/js/ui.js

@@ -8,6 +8,7 @@ var CodeEditorUI = Emitter.extend({
 
     this.xDragbar = null;
     this.yDragbar = null;
+    this.oldXDragPosition = null;
     this.oldYDragPosition = null;
   },
 
@@ -29,9 +30,18 @@ var CodeEditorUI = Emitter.extend({
     });
     this.xDragbar.draggable({
       axis: "x",
+      start: function(event, ui) {
+        self.oldXDragPosition = self.xDragbar.css("left");
+      },
       stop: function(event, ui) {
         var width = $(self.view._nodes.content).width();
         var r = 100.0 * (event.pageX) / width;
+        //prevent overflow if event.pageX > width 
+        //which might be the case if editor is shown on two screens
+        if (r > 100.0) {
+          self.xDragbar.css("left", self.oldXDragPosition);
+          return;
+        }
         self.setInputOutputRatio(r);
         self.view.setPreference("inputOutputRatio", r);
       }