Fix for missing panel buttons

platform/schemas/panel.schema.json

@@ -29,6 +29,17 @@
         "editorPanel": {
             "description": "For tools that create editor instances e.g. language workbenches, reference to the id of a panel of editorActivity that is the editor instance.",
             "type": "string"
+        },
+        "buttons": {
+            "description": "Buttons to use instead of the default buttons defined by the panel. Can be a Button object or an Object with a ref attribute whose value is the id of a button from the panel's definition.",
+            "type": "array",
+            "items": {
+                "type": "object", 
+                "oneOf": [
+                    {"$ref": "button.schema.json"},
+                    {"$ref": "ref.schema.json"}
+                 ]
+            }
         }
     },
     "required": ["id", "name", "ref"]

platform/schemas/ref.schema.json

@@ -0,0 +1,15 @@
+{
+    "$id": "https://mde-network.com/ep/ref.schema.json",
+    "$schema": "http://json-schema.org/draft-07/schema",
+    "title": "EP Ref1",
+    "description": "The MDENet education platform reference",
+
+    "type": "object",
+    "properties": {
+        "ref": {
+            "description": "The id of an education platform element.",
+            "type": "string"
+        }
+    },
+    "required": ["ref"]
+}

platform/src/Playground.js

@@ -379,7 +379,7 @@ function createPanelForDefinitionId(panel){
             // No activity defined buttons
             newPanel.addButtons( Button.createButtons( panelDefinition.buttons, panel.id));
 
-        } else if (panel.buttons != null && panelDefinition.buttons == null) {
+        } else if (panel.buttons != null && panelDefinition.buttons != null) {
             // The activity has defined the buttons
             let resolvedButtonConfigs = panel.buttons.map(btn =>{    
                 let resolvedButton;