diff --git a/typescript/widget/multilayersingletree/multilayersingletree.leveltree.ts b/typescript/widget/multilayersingletree/multilayersingletree.leveltree.ts
index 6a73c932ea..1267f6196b 100644
--- a/typescript/widget/multilayersingletree/multilayersingletree.leveltree.ts
+++ b/typescript/widget/multilayersingletree/multilayersingletree.leveltree.ts
@@ -2,6 +2,7 @@ import { Pane } from '../../base/pane'
 
 export declare class MultiLayerSingleLevelTree extends Pane {
     static xtype: string;
+    static EVENT_CHANGE: string;
 
     initTree(nodes: any, ...args: any[]): void;