MOBILE-4842 calendar: Fix leaving edit view when offline

formElement is not loaded when offline because it's not shown

Author: crazyserver

src/addons/calendar/pages/edit-event/edit-event.ts

@@ -71,8 +71,7 @@ import { DEFAULT_TEXT_FORMAT } from '@singletons/text';
 })
 export default class AddonCalendarEditEventPage implements OnInit, OnDestroy, CanLeave {
 
-    readonly descriptionEditor = viewChild.required(CoreEditorRichTextEditorComponent);
-    readonly formElement = viewChild.required<ElementRef<HTMLFormElement>>('editEventForm');
+    readonly formElement = viewChild<ElementRef<HTMLFormElement>>('editEventForm');
 
     title = 'addon.calendar.newevent';
     component = ADDON_CALENDAR_COMPONENT;
@@ -160,8 +159,6 @@ export default class AddonCalendarEditEventPage implements OnInit, OnDestroy, Ca
 
     /**
      * Fetch the data needed to render the form.
-     *
-     * @returns Promise resolved when done.
      */
     protected async fetchData(): Promise<void> {
         this.error = false;
@@ -448,7 +445,6 @@ export default class AddonCalendarEditEventPage implements OnInit, OnDestroy, Ca
      * Load groups of a certain course.
      *
      * @param courseId Course ID.
-     * @returns Promise resolved when done.
      */
     protected async loadGroups(courseId: number): Promise<void> {
         this.loadingGroups = true;
@@ -629,8 +625,6 @@ export default class AddonCalendarEditEventPage implements OnInit, OnDestroy, Ca
 
     /**
      * Init reminders.
-     *
-     * @returns Promise resolved when done.
      */
     protected async initReminders(): Promise<void> {
         // Don't init reminders when editing an event. Right now, only allow adding reminders for new events.

src/addons/calendar/pages/event/event.html

@@ -16,8 +16,8 @@ <h1>
                 <core-context-menu-item [hidden]="!eventLoaded || (!hasOffline && event && !event.deleted) || !isOnline()" [priority]="400"
                     [content]="'core.settings.synchronizenow' | translate" (action)="doRefresh(undefined, $event, true)"
                     [iconAction]="syncIcon" [closeOnClick]="false" />
-                <core-context-menu-item [hidden]="!event || !event.canedit || event.deleted || (!canEdit && event.id > 0)" [priority]="300"
-                    [content]="'core.edit' | translate" (action)="openEdit()" iconAction="fas-pen" />
+                <core-context-menu-item [hidden]="!event || !event.canedit || event.deleted || (!canEdit && event.id > 0) || !isOnline()"
+                    [priority]="300" [content]="'core.edit' | translate" (action)="openEdit()" iconAction="fas-pen" />
                 <core-context-menu-item [hidden]="!event || !event.candelete || event.deleted" [priority]="200"
                     [content]="'core.delete' | translate" (action)="deleteEvent()" iconAction="fas-trash" />
                 <core-context-menu-item [hidden]="!event || !event.deleted" [priority]="200" [content]="'core.restore' | translate"