fix touch menu toggle

src/app/ui/main/main.component.ts

@@ -17,8 +17,7 @@ import { MatSidenav } from '@angular/material/sidenav';
 })
 export class MainComponent {
 
-  @ViewChild(MatSidenav) sidenav: MatSidenav;
-
+  opened : boolean = true;
   darkTheme = "false";
   title = 'we.bstly';
   currentLocale: String;
@@ -53,9 +52,9 @@ export class MainComponent {
 
     const width = window.innerWidth || document.documentElement.clientWidth || document.body.clientWidth;
     if (width < 768) {
-      this.sidenav?.close();
+      this.opened = false;
     } else {
-      this.sidenav?.open();
+      this.opened = true;
     }
 
     if (localStorage.getItem("bstly.darkTheme") == "true") {
@@ -145,9 +144,9 @@ export class MainComponent {
   @HostListener('window:resize', [ '$event' ])
   onResize(event) {
     if (event.target.innerWidth < 768) {
-      this.sidenav?.close();
+      this.opened = false;
     } else {
-      this.sidenav?.open();
+      this.opened = true;
     }
   }
 
@@ -170,10 +169,10 @@ export class MainComponent {
         const touchDiff = this.touchStartX - this.touchX;
         this.touchStartX = 0;
         this.touchX = 0;
-        if (touchDiff < 0 && touchDiff < (this.touchThresh * -1) && !this.sidenav.opened) {
-          this.sidenav.open();
-        } else if (touchDiff > 0 && touchDiff > this.touchThresh && this.sidenav.opened) {
-          this.sidenav.close();
+        if (touchDiff < 0 && touchDiff < (this.touchThresh * -1) && !this.opened) {
+          this.opened = true;
+        } else if (touchDiff > 0 && touchDiff > this.touchThresh && this.opened) {
+          this.opened = false;
         }
       }
     })