diff --git a/lib/ReactViews/Custom/registerCustomComponentTypes.js b/lib/ReactViews/Custom/registerCustomComponentTypes.js
index <HASH>..<HASH> 100644
--- a/lib/ReactViews/Custom/registerCustomComponentTypes.js
+++ b/lib/ReactViews/Custom/registerCustomComponentTypes.js
@@ -153,7 +153,7 @@ const registerCustomComponentTypes = function(terria) {
 
         const colors = splitStringIfDefined(node.attribs['colors']);
         if (defined(colors)) {
-            var getColorCallback = function(columnId) {
+            const getColorCallback = function(columnId) {
                 return colors[columnId];
             };
             tableStructure.getColorCallback = getColorCallback;
change to fix lint warning