fix: TypeError: Cannot read property 'timeSrv' of undefined

.vscode/launch.json

@@ -5,7 +5,7 @@
       "type": "chrome",
       "request": "launch",
       "name": "Launch Chrome against localhost",
-      "url": "http://localhost:3000/d/Votr2gvmk/nginx",
+      "url": "http://localhost:3000/",
       "sourceMaps": true,
       "pathMapping": {
         "/public/plugins/hastic-graph-panel": "${workspaceFolder}/dist"

src/panel/graph_panel/graph_renderer.ts

@@ -58,6 +58,8 @@ export class GraphRenderer {
 
   constructor($elem: JQuery<HTMLElement>, timeSrv, contextSrv, scope) {
 
+    
+
     var self = this;
     this.$elem = $elem;
     this.ctrl = scope.ctrl;
@@ -164,7 +166,7 @@ export class GraphRenderer {
       //   this.eventManager.updateTime(selectionEvent.xaxis);
       // }, 100);
     } else {
-      this.scope.$apply(function() {
+      this.scope.$apply(() => {
         this.timeSrv.setTime({
           from: moment.utc(selectionEvent.xaxis.from),
           to: moment.utc(selectionEvent.xaxis.to),