MOBILE-3833 navigator: Add required route params functions

src/addons/calendar/pages/event/event.page.ts

@@ -147,7 +147,16 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
      * View loaded.
      */
     ngOnInit(): void {
-        this.eventId = CoreNavigator.getRouteNumberParam('id')!;
+        try {
+            this.eventId = CoreNavigator.getRequiredRouteNumberParam('id');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
+
         this.syncIcon = CoreConstants.ICON_LOADING;
 
         this.fetchEvent();

src/addons/competency/pages/competency/competency.ts

@@ -60,12 +60,20 @@ export class AddonCompetencyCompetencyPage implements OnInit {
      * @inheritdoc
      */
     async ngOnInit(): Promise<void> {
-        this.competencyId = CoreNavigator.getRouteNumberParam('competencyId')!;
+        try {
+            this.competencyId = CoreNavigator.getRequiredRouteNumberParam('competencyId');
             this.planId = CoreNavigator.getRouteNumberParam('planId');
             if (!this.planId) {
-            this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+                this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
                 this.userId = CoreNavigator.getRouteNumberParam('userId');
             }
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         try {
             await this.fetchCompetency();

src/addons/competency/pages/competencysummary/competencysummary.ts

@@ -40,9 +40,17 @@ export class AddonCompetencyCompetencySummaryPage implements OnInit {
      * @inheritdoc
      */
     async ngOnInit(): Promise<void> {
-        this.competencyId = CoreNavigator.getRouteNumberParam('competencyId')!;
+        try {
+            this.competencyId = CoreNavigator.getRequiredRouteNumberParam('competencyId');
             this.contextLevel = CoreNavigator.getRouteParam<ContextLevel>('contextLevel');
             this.contextInstanceId = CoreNavigator.getRouteNumberParam('contextInstanceId');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         try {
             await this.fetchCompetency();

src/addons/competency/pages/coursecompetencies/coursecompetencies.page.ts

@@ -42,8 +42,16 @@ export class AddonCompetencyCourseCompetenciesPage implements OnInit {
      * View loaded.
      */
     ngOnInit(): void {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+        try {
-        this.userId = CoreNavigator.getRouteNumberParam('userId')!;
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
+            this.userId = CoreNavigator.getRequiredRouteNumberParam('userId');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         this.fetchCourseCompetencies().finally(() => {
             this.competenciesLoaded = true;

src/addons/competency/pages/plan/plan.ts

@@ -39,7 +39,15 @@ export class AddonCompetencyPlanPage implements OnInit {
      * @inheritdoc
      */
     ngOnInit(): void {
-        this.planId = CoreNavigator.getRouteNumberParam('planId')!;
+        try {
+            this.planId = CoreNavigator.getRequiredRouteNumberParam('planId');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         this.fetchLearningPlan().finally(() => {
             this.loaded = true;

src/addons/coursecompletion/pages/report/report.ts

@@ -44,11 +44,15 @@ export class AddonCourseCompletionReportPage implements OnInit {
      * @inheritdoc
      */
     ngOnInit(): void {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+        try {
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
             this.userId = CoreNavigator.getRouteNumberParam('userId') || CoreSites.getCurrentSiteUserId();
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
 
-        if (!this.userId) {
+            CoreNavigator.back();
-            this.userId = CoreSites.getCurrentSiteUserId();
+
+            return;
         }
 
         this.fetchCompletion().finally(() => {

src/addons/mod/assign/pages/edit/edit.ts

@@ -78,9 +78,17 @@ export class AddonModAssignEditPage implements OnInit, OnDestroy, CanLeave {
      * Component being initialized.
      */
     ngOnInit(): void {
-        this.moduleId = CoreNavigator.getRouteNumberParam('cmId')!;
+        try {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+            this.moduleId = CoreNavigator.getRequiredRouteNumberParam('cmId');
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
             this.isBlind = !!CoreNavigator.getRouteNumberParam('blindId');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         this.fetchAssignment().finally(() => {
             this.loaded = true;

src/addons/mod/assign/pages/submission-list/submission-list.page.ts

@@ -120,10 +120,18 @@ export class AddonModAssignSubmissionListPage implements AfterViewInit, OnDestro
      * Component being initialized.
      */
     ngAfterViewInit(): void {
-        this.moduleId = CoreNavigator.getRouteNumberParam('cmId')!;
+        try {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+            this.moduleId = CoreNavigator.getRequiredRouteNumberParam('cmId');
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
             this.groupId = CoreNavigator.getRouteNumberParam('groupId') || 0;
             this.selectedStatus = CoreNavigator.getRouteParam('status');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         if (this.selectedStatus) {
             if (this.selectedStatus == AddonModAssignProvider.NEED_GRADING) {

src/addons/mod/assign/pages/submission-review/submission-review.ts

@@ -55,10 +55,18 @@ export class AddonModAssignSubmissionReviewPage implements OnInit, CanLeave {
      */
     ngOnInit(): void {
         this.route.queryParams.subscribe((params) => {
-            this.moduleId = CoreNavigator.getRouteNumberParam('cmId')!;
+            try {
-            this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+                this.moduleId = CoreNavigator.getRequiredRouteNumberParam('cmId');
+                this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
                 this.submitId = CoreNavigator.getRouteNumberParam('submitId') || 0;
                 this.blindId = CoreNavigator.getRouteNumberParam('blindId', { params });
+            } catch (error) {
+                CoreDomUtils.showErrorModal(error);
+
+                CoreNavigator.back();
+
+                return;
+            }
 
             this.fetchSubmission().finally(() => {
                 this.loaded = true;

src/addons/mod/chat/pages/chat/chat.ts

@@ -78,12 +78,12 @@ export class AddonModChatChatPage implements OnInit, OnDestroy, CanLeave {
      * @inheritdoc
      */
     async ngOnInit(): Promise<void> {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+        try {
-        this.cmId = CoreNavigator.getRouteNumberParam('cmId')!;
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
-        this.chatId = CoreNavigator.getRouteNumberParam('chatId')!;
+            this.cmId = CoreNavigator.getRequiredRouteNumberParam('cmId');
+            this.chatId = CoreNavigator.getRequiredRouteNumberParam('chatId');
             this.title = CoreNavigator.getRouteParam('title') || '';
 
-        try {
             await this.loginUser();
 
             await this.fetchMessages();

src/addons/mod/chat/pages/session-messages/session-messages.ts

@@ -47,12 +47,20 @@ export class AddonModChatSessionMessagesPage implements OnInit {
      * @inheritdoc
      */
     ngOnInit(): void {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+        try {
-        this.cmId = CoreNavigator.getRouteNumberParam('cmId')!;
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
-        this.sessionStart = CoreNavigator.getRouteNumberParam('sessionStart')!;
+            this.cmId = CoreNavigator.getRequiredRouteNumberParam('cmId');
-        this.sessionEnd = CoreNavigator.getRouteNumberParam('sessionEnd')!;
+            this.sessionStart = CoreNavigator.getRequiredRouteNumberParam('sessionStart');
-        this.chatId = CoreNavigator.getRouteNumberParam('chatId')!;
+            this.sessionEnd = CoreNavigator.getRequiredRouteNumberParam('sessionEnd');
+            this.chatId = CoreNavigator.getRequiredRouteNumberParam('chatId');
             this.groupId = CoreNavigator.getRouteNumberParam('groupId') || 0;
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         this.currentUserId = CoreSites.getCurrentSiteUserId();
 

src/addons/mod/chat/pages/sessions/sessions.ts

@@ -53,10 +53,18 @@ export class AddonModChatSessionsPage implements AfterViewInit, OnDestroy {
      * @inheritdoc
      */
     async ngAfterViewInit(): Promise<void> {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+        try {
-        this.cmId = CoreNavigator.getRouteNumberParam('cmId')!;
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
-        this.chatId = CoreNavigator.getRouteNumberParam('chatId')!;
+            this.cmId = CoreNavigator.getRequiredRouteNumberParam('cmId');
+            this.chatId = CoreNavigator.getRequiredRouteNumberParam('chatId');
             this.sessions.setChatId(this.chatId);
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         await this.fetchSessions();
 

src/addons/mod/data/components/field-plugin/field-plugin.ts

@@ -53,7 +53,7 @@ export class AddonModDataFieldPluginComponent implements OnInit, OnChanges {
             return;
         }
 
-        try{
+        try {
             // Check if the plugin has defined its own component to render itself.
             this.fieldComponent = await AddonModDataFieldsDelegate.getComponentForField(this.field);
 

src/addons/mod/data/pages/edit/edit.ts

@@ -96,10 +96,18 @@ export class AddonModDataEditPage implements OnInit {
      * @inheritdoc
      */
     ngOnInit(): void {
-        this.module = CoreNavigator.getRouteParam<CoreCourseModule>('module')!;
+        try {
+            this.module = CoreNavigator.getRequiredRouteParam<CoreCourseModule>('module');
             this.entryId = CoreNavigator.getRouteNumberParam('entryId') || undefined;
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
             this.selectedGroup = CoreNavigator.getRouteNumberParam('group') || 0;
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         // If entryId is lower than 0 or null, it is a new entry or an offline entry.
         this.isEditing = typeof this.entryId != 'undefined' && this.entryId > 0;

src/addons/mod/data/pages/entry/entry.ts

@@ -132,11 +132,20 @@ export class AddonModDataEntryPage implements OnInit, OnDestroy {
      * @inheritdoc
      */
     async ngOnInit(): Promise<void> {
-        this.module = CoreNavigator.getRouteParam<CoreCourseModule>('module')!;
+        try {
+            this.module = CoreNavigator.getRequiredRouteParam<CoreCourseModule>('module');
             this.entryId = CoreNavigator.getRouteNumberParam('entryId') || undefined;
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
             this.selectedGroup = CoreNavigator.getRouteNumberParam('group') || 0;
             this.offset = CoreNavigator.getRouteNumberParam('offset');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
+
         this.title = this.module.name;
 
         this.commentsEnabled = !CoreComments.areCommentsDisabledInSite();

src/addons/mod/feedback/pages/attempt/attempt.ts

@@ -49,9 +49,17 @@ export class AddonModFeedbackAttemptPage implements OnInit {
      * @inheritdoc
      */
     ngOnInit(): void {
-        this.cmId = CoreNavigator.getRouteNumberParam('cmId')!;
+        try {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+            this.cmId = CoreNavigator.getRequiredRouteNumberParam('cmId');
-        this.attemptId = CoreNavigator.getRouteNumberParam('attemptId')!;
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
+            this.attemptId = CoreNavigator.getRequiredRouteNumberParam('attemptId');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         this.fetchData();
     }

src/addons/mod/feedback/pages/form/form.ts

@@ -92,12 +92,20 @@ export class AddonModFeedbackFormPage implements OnInit, OnDestroy, CanLeave {
      * @inheritdoc
      */
     async ngOnInit(): Promise<void> {
-        this.cmId = CoreNavigator.getRouteNumberParam('cmId')!;
+        try {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+            this.cmId = CoreNavigator.getRequiredRouteNumberParam('cmId');
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
             this.currentPage = CoreNavigator.getRouteNumberParam('page');
             this.title = CoreNavigator.getRouteParam('title');
             this.preview = !!CoreNavigator.getRouteBooleanParam('preview');
             this.fromIndex = !!CoreNavigator.getRouteBooleanParam('fromIndex');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         await this.fetchData();
 

src/addons/mod/feedback/pages/nonrespondents/nonrespondents.ts

@@ -47,9 +47,17 @@ export class AddonModFeedbackNonRespondentsPage implements OnInit {
      * @inheritdoc
      */
     ngOnInit(): void {
-        this.cmId = CoreNavigator.getRouteNumberParam('cmId')!;
+        try {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+            this.cmId = CoreNavigator.getRequiredRouteNumberParam('cmId');
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
             this.selectedGroup = CoreNavigator.getRouteNumberParam('group') || 0;
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         this.fetchData();
     }

src/addons/mod/feedback/pages/respondents/respondents.ts

@@ -63,9 +63,17 @@ export class AddonModFeedbackRespondentsPage implements AfterViewInit {
      * @inheritdoc
      */
     async ngAfterViewInit(): Promise<void> {
-        this.cmId = CoreNavigator.getRouteNumberParam('cmId')!;
+        try {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+            this.cmId = CoreNavigator.getRequiredRouteNumberParam('cmId');
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
             this.selectedGroup = CoreNavigator.getRouteNumberParam('group') || 0;
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         await this.fetchData();
 

src/addons/mod/forum/pages/discussion/discussion.page.ts

@@ -65,7 +65,7 @@ export class AddonModForumDiscussionPage implements OnInit, AfterViewInit, OnDes
     discussionId!: number;
     forum: Partial<AddonModForumData> = {};
     accessInfo: AddonModForumAccessInformation = {};
-    discussion!: AddonModForumDiscussion;
+    discussion?: AddonModForumDiscussion;
     startingPost?: Post;
     posts!: Post[];
     discussionLoaded = false;
@@ -100,8 +100,8 @@ export class AddonModForumDiscussionPage implements OnInit, AfterViewInit, OnDes
     leavingPage = false;
 
     protected forumId!: number;
-    protected postId!: number;
+    protected postId?: number;
-    protected parent!: number;
+    protected parent?: number;
     protected onlineObserver?: Subscription;
     protected syncObserver?: CoreEventObserver;
     protected syncManualObserver?: CoreEventObserver;
@@ -122,16 +122,25 @@ export class AddonModForumDiscussionPage implements OnInit, AfterViewInit, OnDes
     }
 
     ngOnInit(): void {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+        try {
-        this.cmId = CoreNavigator.getRouteNumberParam('cmId')!;
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
-        this.forumId = CoreNavigator.getRouteNumberParam('forumId')!;
+            this.cmId = CoreNavigator.getRequiredRouteNumberParam('cmId');
-        this.discussion = CoreNavigator.getRouteParam<AddonModForumDiscussion>('discussion')!;
+            this.forumId = CoreNavigator.getRequiredRouteNumberParam('forumId');
+            this.discussion = CoreNavigator.getRouteParam<AddonModForumDiscussion>('discussion');
             this.discussionId = this.discussion
                 ? this.discussion.discussion
-            : CoreNavigator.getRouteNumberParam('discussionId')!;
+                : CoreNavigator.getRequiredRouteNumberParam('discussionId');
-        this.trackPosts = CoreNavigator.getRouteBooleanParam('trackPosts')!;
+            this.trackPosts = CoreNavigator.getRouteBooleanParam('trackPosts') || false;
-        this.postId = CoreNavigator.getRouteNumberParam('postId')!;
+            this.postId = CoreNavigator.getRouteNumberParam('postId');
-        this.parent = CoreNavigator.getRouteNumberParam('parent')!;
+            this.parent = CoreNavigator.getRouteNumberParam('parent');
+
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            this.goBack();
+
+            return;
+        }
 
         this.isOnline = CoreApp.isOnline();
         this.onlineObserver = Network.onChange().subscribe(() => {
@@ -148,11 +157,9 @@ export class AddonModForumDiscussionPage implements OnInit, AfterViewInit, OnDes
      * View loaded.
      */
     async ngAfterViewInit(): Promise<void> {
-        if (this.parent) {
+        this.sort = this.parent
-            this.sort = 'nested'; // Force nested order.
+            ? 'nested' // Force nested order.
-        } else {
+            : await this.getUserSort();
-            this.sort = await this.getUserSort();
-        }
 
         await this.fetchPosts(true, false, true);
 
@@ -183,6 +190,16 @@ export class AddonModForumDiscussionPage implements OnInit, AfterViewInit, OnDes
             await this.loadDiscussion(this.forumId, this.cmId, this.discussionId);
         }
 
+        if (!this.discussion) {
+            CoreDomUtils.showErrorModal('Cannot get the discussion');
+
+            this.goBack();
+
+            return;
+        }
+
+        const discussion = this.discussion;
+
         // Refresh data if this discussion is synchronized automatically.
         this.syncObserver = CoreEvents.on(AddonModForumSyncProvider.AUTO_SYNCED, data => {
             if (data.forumId == this.forumId && this.discussionId == data.discussionId
@@ -204,7 +221,7 @@ export class AddonModForumDiscussionPage implements OnInit, AfterViewInit, OnDes
         }, CoreSites.getCurrentSiteId());
 
         // Invalidate discussion list if it was not read.
-        if (this.discussion.numunread > 0) {
+        if (discussion.numunread > 0) {
             AddonModForum.invalidateDiscussionsList(this.forumId);
         }
 
@@ -227,22 +244,18 @@ export class AddonModForumDiscussionPage implements OnInit, AfterViewInit, OnDes
             if ((this.forumId && this.forumId === data.forumId) || data.cmId === this.cmId) {
                 AddonModForum.invalidateDiscussionsList(this.forumId).finally(() => {
                     if (typeof data.locked != 'undefined') {
-                        this.discussion.locked = data.locked;
+                        discussion.locked = data.locked;
                     }
                     if (typeof data.pinned != 'undefined') {
-                        this.discussion.pinned = data.pinned;
+                        discussion.pinned = data.pinned;
                     }
                     if (typeof data.starred != 'undefined') {
-                        this.discussion.starred = data.starred;
+                        discussion.starred = data.starred;
                     }
 
                     if (typeof data.deleted != 'undefined' && data.deleted) {
                         if (!data.post?.parentid) {
-                            if (this.splitView?.outletActivated) {
+                            this.goBack();
-                                CoreNavigator.navigate('../');
-                            } else {
-                                CoreNavigator.back();
-                            }
                         } else {
                             this.discussionLoaded = false;
                             this.refreshPosts();
@@ -272,6 +285,17 @@ export class AddonModForumDiscussionPage implements OnInit, AfterViewInit, OnDes
         return true;
     }
 
+    /**
+     * Helper function to go back.
+     */
+    protected goBack(): void {
+        if (this.splitView?.outletActivated) {
+            CoreNavigator.navigate('../');
+        } else {
+            CoreNavigator.back();
+        }
+    }
+
     /**
      * Runs when the page is about to leave and no longer be the active page.
      */
@@ -515,7 +539,7 @@ export class AddonModForumDiscussionPage implements OnInit, AfterViewInit, OnDes
             this.syncIcon = CoreConstants.ICON_SYNC;
 
             if (forceMarkAsRead || (hasUnreadPosts && this.trackPosts)) {
-                // // Add log in Moodle and mark unread posts as readed.
+                // Add log in Moodle and mark unread posts as readed.
                 AddonModForum.logDiscussionView(this.discussionId, this.forumId || -1, this.forum.name).catch(() => {
                     // Ignore errors.
                 }).finally(() => {
@@ -543,14 +567,8 @@ export class AddonModForumDiscussionPage implements OnInit, AfterViewInit, OnDes
             return;
         }
 
-        try {
+        this.discussion = await AddonModForumHelper.getDiscussionById(forumId, cmId, discussionId);
-            const discussion = await AddonModForumHelper.getDiscussionById(forumId, cmId, discussionId);
-
-            this.discussion = discussion;
         this.discussionId = this.discussion.discussion;
-        } catch (error) {
-            // Ignore errors.
-        }
     }
 
     /**
@@ -630,7 +648,7 @@ export class AddonModForumDiscussionPage implements OnInit, AfterViewInit, OnDes
      * @param showErrors Whether to show errors in a modal.
      * @return Promise resolved when done.
      */
-    refreshPosts(sync?: boolean, showErrors?: boolean): Promise<void> {
+    async refreshPosts(sync?: boolean, showErrors?: boolean): Promise<void> {
         this.content.scrollToTop();
         this.refreshIcon = CoreConstants.ICON_LOADING;
         this.syncIcon = CoreConstants.ICON_LOADING;
@@ -642,9 +660,9 @@ export class AddonModForumDiscussionPage implements OnInit, AfterViewInit, OnDes
             AddonModForum.invalidateCanAddDiscussion(this.forumId),
         ];
 
-        return CoreUtils.allPromises(promises).catch(() => {
+        await CoreUtils.ignoreErrors(CoreUtils.allPromises(promises));
-            // Ignore errors.
+
-        }).then(() => this.fetchPosts(sync, showErrors));
+        await this.fetchPosts(sync, showErrors);
     }
 
     /**
@@ -668,6 +686,10 @@ export class AddonModForumDiscussionPage implements OnInit, AfterViewInit, OnDes
      * @param locked True to lock the discussion, false to unlock.
      */
     async setLockState(locked: boolean): Promise<void> {
+        if (!this.discussion) {
+            return;
+        }
+
         const modal = await CoreDomUtils.showModalLoading('core.sending', true);
 
         try {
@@ -696,6 +718,10 @@ export class AddonModForumDiscussionPage implements OnInit, AfterViewInit, OnDes
      * @param pinned True to pin the discussion, false to unpin it.
      */
     async setPinState(pinned: boolean): Promise<void> {
+        if (!this.discussion) {
+            return;
+        }
+
         const modal = await CoreDomUtils.showModalLoading('core.sending', true);
 
         try {
@@ -725,6 +751,10 @@ export class AddonModForumDiscussionPage implements OnInit, AfterViewInit, OnDes
      * @param starred True to star the discussion, false to unstar it.
      */
     async toggleFavouriteState(starred: boolean): Promise<void> {
+        if (!this.discussion) {
+            return;
+        }
+
         const modal = await CoreDomUtils.showModalLoading('core.sending', true);
 
         try {

src/addons/mod/forum/pages/new-discussion/new-discussion.page.ts

@@ -103,10 +103,18 @@ export class AddonModForumNewDiscussionPage implements OnInit, OnDestroy, CanLea
      * Component being initialized.
      */
     ngOnInit(): void {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+        try {
-        this.cmId = CoreNavigator.getRouteNumberParam('cmId')!;
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
-        this.forumId = CoreNavigator.getRouteNumberParam('forumId')!;
+            this.cmId = CoreNavigator.getRequiredRouteNumberParam('cmId');
-        this.timeCreated = CoreNavigator.getRouteNumberParam('timeCreated')!;
+            this.forumId = CoreNavigator.getRequiredRouteNumberParam('forumId');
+            this.timeCreated = CoreNavigator.getRequiredRouteNumberParam('timeCreated');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            this.goBack();
+
+            return;
+        }
 
         this.fetchDiscussionData().finally(() => {
             this.groupsLoaded = true;
@@ -595,6 +603,17 @@ export class AddonModForumNewDiscussionPage implements OnInit, OnDestroy, CanLea
         delete this.syncObserver;
     }
 
+    /**
+     * Helper function to go back.
+     */
+    protected goBack(): void {
+        if (this.splitView?.outletActivated) {
+            CoreNavigator.navigate('../../');
+        } else {
+            CoreNavigator.back();
+        }
+    }
+
     /**
      * Page destroyed.
      */

src/addons/mod/glossary/pages/edit/edit.ts

@@ -73,7 +73,7 @@ export class AddonModGlossaryEditPage implements OnInit, CanLeave {
     };
 
     protected timecreated!: number;
-    protected concept?: string;
+    protected concept = '';
     protected syncId?: string;
     protected syncObserver?: CoreEventObserver;
     protected isDestroyed = false;
@@ -86,11 +86,19 @@ export class AddonModGlossaryEditPage implements OnInit, CanLeave {
      * Component being initialized.
      */
     ngOnInit(): void {
-        this.cmId = CoreNavigator.getRouteNumberParam('cmId')!;
+        try {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+            this.cmId = CoreNavigator.getRequiredRouteNumberParam('cmId');
-        this.timecreated = CoreNavigator.getRouteNumberParam('timecreated')!;
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
-        this.concept = CoreNavigator.getRouteParam<string>('concept')!;
+            this.timecreated = CoreNavigator.getRequiredRouteNumberParam('timecreated');
+            this.concept = CoreNavigator.getRouteParam<string>('concept') || '';
             this.editorExtraParams.timecreated = this.timecreated;
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            this.goBack();
+
+            return;
+        }
 
         this.fetchData();
     }
@@ -116,7 +124,7 @@ export class AddonModGlossaryEditPage implements OnInit, CanLeave {
         } catch (error) {
             CoreDomUtils.showErrorModalDefault(error, 'addon.mod_glossary.errorloadingglossary', true);
 
-            CoreNavigator.back();
+            this.goBack();
         }
     }
 
@@ -126,7 +134,7 @@ export class AddonModGlossaryEditPage implements OnInit, CanLeave {
      * @return Promise resolved when done.
      */
     protected async loadOfflineData(): Promise<void> {
-        const entry = await AddonModGlossaryOffline.getNewEntry(this.glossary!.id, this.concept || '', this.timecreated);
+        const entry = await AddonModGlossaryOffline.getNewEntry(this.glossary!.id, this.concept, this.timecreated);
 
         this.entry.concept = entry.concept || '';
         this.entry.definition = entry.definition || '';
@@ -367,4 +375,15 @@ export class AddonModGlossaryEditPage implements OnInit, CanLeave {
         }
     }
 
+    /**
+     * Helper function to go back.
+     */
+    protected goBack(): void {
+        if (this.splitView?.outletActivated) {
+            CoreNavigator.navigate('../../');
+        } else {
+            CoreNavigator.back();
+        }
+    }
+
 }

src/addons/mod/glossary/pages/entry/entry.ts

@@ -57,10 +57,18 @@ export class AddonModGlossaryEntryPage implements OnInit {
      * @inheritdoc
      */
     async ngOnInit(): Promise<void> {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+        try {
-        this.entryId = CoreNavigator.getRouteNumberParam('entryId')!;
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
+            this.entryId = CoreNavigator.getRequiredRouteNumberParam('entryId');
             this.tagsEnabled = CoreTag.areTagsAvailableInSite();
             this.commentsEnabled = !CoreComments.areCommentsDisabledInSite();
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         try {
             await this.fetchEntry();

src/addons/mod/h5pactivity/pages/attempt-results/attempt-results.ts

@@ -50,9 +50,17 @@ export class AddonModH5PActivityAttemptResultsPage implements OnInit {
      * @inheritdoc
      */
     async ngOnInit(): Promise<void> {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+        try {
-        this.cmId = CoreNavigator.getRouteNumberParam('cmId')!;
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
-        this.attemptId = CoreNavigator.getRouteNumberParam('attemptId')!;
+            this.cmId = CoreNavigator.getRequiredRouteNumberParam('cmId');
+            this.attemptId = CoreNavigator.getRequiredRouteNumberParam('attemptId');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         try {
             await this.fetchData();

src/addons/mod/h5pactivity/pages/user-attempts/user-attempts.ts

@@ -51,9 +51,18 @@ export class AddonModH5PActivityUserAttemptsPage implements OnInit {
      * @inheritdoc
      */
     async ngOnInit(): Promise<void> {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+        try {
-        this.cmId = CoreNavigator.getRouteNumberParam('cmId')!;
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
+            this.cmId = CoreNavigator.getRequiredRouteNumberParam('cmId');
             this.userId = CoreNavigator.getRouteNumberParam('userId') || CoreSites.getCurrentSiteUserId();
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
+
         this.isCurrentUser = this.userId == CoreSites.getCurrentSiteUserId();
 
         try {

src/addons/mod/h5pactivity/pages/users-attempts/users-attempts.ts

@@ -49,8 +49,16 @@ export class AddonModH5PActivityUsersAttemptsPage implements OnInit {
      * @inheritdoc
      */
     async ngOnInit(): Promise<void> {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+        try {
-        this.cmId = CoreNavigator.getRouteNumberParam('cmId')!;
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
+            this.cmId = CoreNavigator.getRequiredRouteNumberParam('cmId');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         try {
             await this.fetchData();

src/addons/mod/lesson/pages/player/player.page.ts

@@ -119,12 +119,20 @@ export class AddonModLessonPlayerPage implements OnInit, OnDestroy, CanLeave {
      * Component being initialized.
      */
     async ngOnInit(): Promise<void> {
-        this.cmId = CoreNavigator.getRouteNumberParam('cmId')!;
+        try {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+            this.cmId = CoreNavigator.getRequiredRouteNumberParam('cmId');
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
             this.password = CoreNavigator.getRouteParam('password');
             this.review = !!CoreNavigator.getRouteBooleanParam('review');
             this.currentPage = CoreNavigator.getRouteNumberParam('pageId');
             this.retakeToReview = CoreNavigator.getRouteNumberParam('retake');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         try {
             // Fetch the Lesson data.

src/addons/mod/lesson/pages/user-retake/user-retake.page.ts

@@ -64,10 +64,18 @@ export class AddonModLessonUserRetakePage implements OnInit {
      * Component being initialized.
      */
     ngOnInit(): void {
-        this.cmId = CoreNavigator.getRouteNumberParam('cmId')!;
+        try {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+            this.cmId = CoreNavigator.getRequiredRouteNumberParam('cmId');
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
             this.userId = CoreNavigator.getRouteNumberParam('userId') || CoreSites.getCurrentSiteUserId();
             this.retakeNumber = CoreNavigator.getRouteNumberParam('retake');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         // Fetch the data.
         this.fetchData().finally(() => {

src/addons/mod/quiz/pages/attempt/attempt.page.ts

@@ -52,9 +52,17 @@ export class AddonModQuizAttemptPage implements OnInit {
      * Component being initialized.
      */
     ngOnInit(): void {
-        this.cmId = CoreNavigator.getRouteNumberParam('cmId')!;
+        try {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+            this.cmId = CoreNavigator.getRequiredRouteNumberParam('cmId');
-        this.attemptId = CoreNavigator.getRouteNumberParam('attemptId')!;
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
+            this.attemptId = CoreNavigator.getRequiredRouteNumberParam('attemptId');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         this.fetchQuizData().finally(() => {
             this.loaded = true;

src/addons/mod/quiz/pages/player/player.page.ts

@@ -106,9 +106,17 @@ export class AddonModQuizPlayerPage implements OnInit, OnDestroy, CanLeave {
      * Component being initialized.
      */
     ngOnInit(): void {
-        this.cmId = CoreNavigator.getRouteNumberParam('cmId')!;
+        try {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+            this.cmId = CoreNavigator.getRequiredRouteNumberParam('cmId');
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
             this.moduleUrl = CoreNavigator.getRouteParam('moduleUrl');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         // Create the auto save instance.
         this.autoSave = new AddonModQuizAutoSave(

src/addons/mod/quiz/pages/review/review.page.ts

@@ -83,11 +83,19 @@ export class AddonModQuizReviewPage implements OnInit {
      * Component being initialized.
      */
     async ngOnInit(): Promise<void> {
-        this.cmId = CoreNavigator.getRouteNumberParam('cmId')!;
+        try {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+            this.cmId = CoreNavigator.getRequiredRouteNumberParam('cmId');
-        this.attemptId = CoreNavigator.getRouteNumberParam('attemptId')!;
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
+            this.attemptId = CoreNavigator.getRequiredRouteNumberParam('attemptId');
             this.currentPage = CoreNavigator.getRouteNumberParam('page') || -1;
             this.showAll = this.currentPage == -1;
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         try {
             await this.fetchData();

src/addons/mod/scorm/pages/player/player.ts

@@ -88,14 +88,22 @@ export class AddonModScormPlayerPage implements OnInit, OnDestroy {
      * @inheritdoc
      */
     async ngOnInit(): Promise<void> {
-        this.cmId = CoreNavigator.getRouteNumberParam('cmId')!;
+        try {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+            this.cmId = CoreNavigator.getRequiredRouteNumberParam('cmId');
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
             this.mode = CoreNavigator.getRouteParam('mode') || AddonModScormProvider.MODENORMAL;
             this.moduleUrl = CoreNavigator.getRouteParam('moduleUrl') || '';
             this.newAttempt = !!CoreNavigator.getRouteBooleanParam('newAttempt');
             this.organizationId = CoreNavigator.getRouteParam('organizationId');
             this.initialScoId = CoreNavigator.getRouteNumberParam('scoId');
             this.siteId = CoreSites.getCurrentSiteId();
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         try {
             // Fetch the SCORM data.

src/addons/mod/workshop/pages/assessment/assessment.ts

@@ -117,10 +117,18 @@ export class AddonModWorkshopAssessmentPage implements OnInit, OnDestroy, CanLea
      * Component being initialized.
      */
     ngOnInit(): void {
-        this.assessment = CoreNavigator.getRouteParam<AddonModWorkshopSubmissionAssessmentWithFormData>('assessment')!;
+        try {
-        this.submission = CoreNavigator.getRouteParam<AddonModWorkshopSubmissionData>('submission')!;
+            this.assessment = CoreNavigator.getRequiredRouteParam<AddonModWorkshopSubmissionAssessmentWithFormData>('assessment');
-        this.profile = CoreNavigator.getRouteParam<CoreUserProfile>('profile')!;
+            this.submission = CoreNavigator.getRequiredRouteParam<AddonModWorkshopSubmissionData>('submission');
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+            this.profile = CoreNavigator.getRequiredRouteParam<CoreUserProfile>('profile');
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         this.assessmentId = this.assessment.id;
         this.workshopId = this.submission.workshopid;

src/addons/mod/workshop/pages/edit-submission/edit-submission.ts

@@ -99,10 +99,18 @@ export class AddonModWorkshopEditSubmissionPage implements OnInit, OnDestroy, Ca
      * Component being initialized.
      */
     ngOnInit(): void {
-        this.module = CoreNavigator.getRouteParam<CoreCourseModule>('module')!;
+        try {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+            this.module = CoreNavigator.getRequiredRouteParam<CoreCourseModule>('module');
-        this.access = CoreNavigator.getRouteParam<AddonModWorkshopGetWorkshopAccessInformationWSResponse>('access')!;
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
+            this.access = CoreNavigator.getRequiredRouteParam<AddonModWorkshopGetWorkshopAccessInformationWSResponse>('access');
             this.submissionId = CoreNavigator.getRouteNumberParam('submissionId') || 0;
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         if (this.submissionId > 0) {
             this.editorExtraParams.id = this.submissionId;

src/addons/mod/workshop/pages/submission/submission.ts

@@ -130,15 +130,22 @@ export class AddonModWorkshopSubmissionPage implements OnInit, OnDestroy, CanLea
      * Component being initialized.
      */
     async ngOnInit(): Promise<void> {
-
+        try {
-        this.submissionId = CoreNavigator.getRouteNumberParam('submissionId')!;
+            this.submissionId = CoreNavigator.getRequiredRouteNumberParam('submissionId');
-        this.module = CoreNavigator.getRouteParam<CoreCourseModule>('module')!;
+            this.module = CoreNavigator.getRequiredRouteParam<CoreCourseModule>('module');
-        this.workshop = CoreNavigator.getRouteParam<AddonModWorkshopData>('workshop')!;
+            this.workshop = CoreNavigator.getRequiredRouteParam<AddonModWorkshopData>('workshop');
-        this.access = CoreNavigator.getRouteParam<AddonModWorkshopGetWorkshopAccessInformationWSResponse>('access')!;
+            this.access = CoreNavigator.getRequiredRouteParam<AddonModWorkshopGetWorkshopAccessInformationWSResponse>('access');
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
             this.profile = CoreNavigator.getRouteParam<CoreUserProfile>('profile');
-        this.submissionInfo = CoreNavigator.getRouteParam<AddonModWorkshopSubmissionDataWithOfflineData>('submission')!;
+            this.submissionInfo = CoreNavigator.getRequiredRouteParam<AddonModWorkshopSubmissionDataWithOfflineData>('submission');
             this.assessment = CoreNavigator.getRouteParam<AddonModWorkshopSubmissionAssessmentWithFormData>('assessment');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         this.title = this.module.name;
         this.workshopId = this.module.instance || this.workshop.id;

src/addons/notes/pages/list/list.page.ts

@@ -40,7 +40,7 @@ export class AddonNotesListPage implements OnInit, OnDestroy {
 
      @ViewChild(IonContent) content?: IonContent;
 
-    courseId: number;
+    courseId!: number;
     userId?: number;
     type: AddonNotesPublishState = 'course';
     refreshIcon = CoreConstants.ICON_LOADING;
@@ -51,13 +51,21 @@ export class AddonNotesListPage implements OnInit, OnDestroy {
     user?: CoreUserProfile;
     showDelete = false;
     canDeleteNotes = false;
-    currentUserId: number;
+    currentUserId!: number;
 
-    protected syncObserver: CoreEventObserver;
+    protected syncObserver!: CoreEventObserver;
 
     constructor() {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+        try {
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
             this.userId = CoreNavigator.getRouteNumberParam('userId');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         // Refresh data if notes are synchronized automatically.
         this.syncObserver = CoreEvents.on(AddonNotesSyncProvider.AUTO_SYNCED, (data) => {

src/addons/privatefiles/pages/index/index.ts

@@ -69,6 +69,7 @@ export class AddonPrivateFilesIndexPage implements OnInit, OnDestroy {
      * Component being initialized.
      */
     ngOnInit(): void {
+        try {
             this.root = CoreNavigator.getRouteParam('root');
             const contextId = CoreNavigator.getRouteNumberParam('contextid');
 
@@ -76,13 +77,20 @@ export class AddonPrivateFilesIndexPage implements OnInit, OnDestroy {
                 // Loading a certain folder.
                 this.path = {
                     contextid: contextId,
-                component: CoreNavigator.getRouteParam<string>('component')!,
+                    component: CoreNavigator.getRequiredRouteParam<string>('component'),
-                filearea: CoreNavigator.getRouteParam<string>('filearea')!,
+                    filearea: CoreNavigator.getRequiredRouteParam<string>('filearea'),
-                itemid: CoreNavigator.getRouteNumberParam('itemid')!,
+                    itemid: CoreNavigator.getRequiredRouteNumberParam('itemid'),
-                filepath: CoreNavigator.getRouteParam<string>('filepath')!,
+                    filepath: CoreNavigator.getRequiredRouteParam<string>('filepath'),
-                filename: CoreNavigator.getRouteParam<string>('filename')!,
+                    filename: CoreNavigator.getRequiredRouteParam<string>('filename'),
                 };
             }
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         this.title = this.path?.filename || Translate.instant('addon.privatefiles.files');
 

src/addons/storagemanager/pages/course-storage/course-storage.ts

@@ -42,7 +42,15 @@ export class AddonStorageManagerCourseStoragePage implements OnInit {
      * View loaded.
      */
     async ngOnInit(): Promise<void> {
-        this.course = CoreNavigator.getRouteParam<CoreEnrolledCourseData>('course')!;
+        try {
+            this.course = CoreNavigator.getRequiredRouteParam<CoreEnrolledCourseData>('course');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         this.sections = await CoreCourse.getSections(this.course.id, false, true);
         CoreCourseHelper.addHandlerDataForModules(this.sections, this.course.id);

src/core/components/split-view/split-view.ts

@@ -66,14 +66,8 @@ export class CoreSplitViewComponent implements AfterViewInit, OnDestroy {
         this.disableScrollOnParent();
 
         this.subscriptions = [
-            this.contentOutlet.activateEvents.subscribe(() => {
+            this.contentOutlet.activateEvents.subscribe(() => this.updateOutletRoute()),
-                this.updateClasses();
+            this.contentOutlet.deactivateEvents.subscribe(() => this.updateOutletRoute()),
-                this.outletRouteSubject.next(this.contentOutlet.activatedRoute.snapshot);
-            }),
-            this.contentOutlet.deactivateEvents.subscribe(() => {
-                this.updateClasses();
-                this.outletRouteSubject.next(null);
-            }),
             CoreScreen.layoutObservable.subscribe(() => this.updateClasses()),
         ];
 
@@ -89,6 +83,17 @@ export class CoreSplitViewComponent implements AfterViewInit, OnDestroy {
         this.enableScrollOnParent();
     }
 
+    /**
+     * Update outlet status.
+     */
+    private updateOutletRoute(): void {
+        const outletRoute = this.contentOutlet.isActivated ? this.contentOutlet.activatedRoute.snapshot : null;
+
+        this.updateClasses();
+
+        this.outletRouteSubject.next(outletRoute);
+    }
+
     /**
      * Update host classes.
      */

src/core/features/comments/pages/viewer/viewer.page.ts

@@ -110,19 +110,28 @@ export class CoreCommentsViewerPage implements OnInit, OnDestroy {
      * View loaded.
      */
     async ngOnInit(): Promise<void> {
+        try {
+            this.contextLevel = CoreNavigator.getRequiredRouteParam<ContextLevel>('contextLevel');
+            this.instanceId = CoreNavigator.getRequiredRouteNumberParam('instanceId');
+            this.componentName = CoreNavigator.getRequiredRouteParam<string>('componentName');
+            this.itemId = CoreNavigator.getRequiredRouteNumberParam('itemId');
+            this.area = CoreNavigator.getRouteParam('area') || '';
+            this.title = CoreNavigator.getRouteNumberParam('title') ||
+                Translate.instant('core.comments.comments');
+            this.courseId = CoreNavigator.getRouteNumberParam('courseId');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
+
         // Is implicit the user can delete if he can add.
         this.addDeleteCommentsAvailable = await CoreComments.isAddCommentsAvailable();
         this.currentUserId = CoreSites.getCurrentSiteUserId();
 
         this.commentsLoaded = false;
-        this.contextLevel = CoreNavigator.getRouteParam<ContextLevel>('contextLevel')!;
-        this.instanceId = CoreNavigator.getRouteNumberParam('instanceId')!;
-        this.componentName = CoreNavigator.getRouteParam<string>('componentName')!;
-        this.itemId = CoreNavigator.getRouteNumberParam('itemId')!;
-        this.area = CoreNavigator.getRouteParam('area') || '';
-        this.title = CoreNavigator.getRouteNumberParam('title') ||
-            Translate.instant('core.comments.comments');
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId');
 
         await this.fetchComments(true);
     }

src/core/features/course/classes/main-activity-page.ts

@@ -14,10 +14,10 @@
 
 import { Component, OnInit } from '@angular/core';
 import { CoreNavigator } from '@services/navigator';
+import { CoreDomUtils } from '@services/utils/dom';
 import { CoreCourseAnyModuleData } from '../services/course';
 import { CoreCourseModuleMainResourceComponent } from './main-resource-component';
 
-/**
 /**
  * Template class to easily create CoreCourseModuleMainComponent of resources (or activities without syncing).
  */
@@ -36,8 +36,17 @@ export class CoreCourseModuleMainActivityPage<ActivityType extends CoreCourseMod
      * Component being initialized.
      */
     ngOnInit(): void {
-        this.module = CoreNavigator.getRouteParam<CoreCourseAnyModuleData>('module')!;
+        try {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+            this.module = CoreNavigator.getRequiredRouteParam<CoreCourseAnyModuleData>('module');
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
+
         this.title = this.module?.name;
     }
 

src/core/features/courses/pages/categories/categories.ts

@@ -59,7 +59,7 @@ export class CoreCoursesCategoriesPage implements OnInit {
      * @return Promise resolved when done.
      */
     protected async fetchCategories(): Promise<void> {
-        try{
+        try {
             const categories: CoreCategoryData[] = await CoreCourses.getCategories(this.categoryId, true);
 
             this.currentCategory = undefined;

src/core/features/grades/pages/course/course.page.ts

@@ -40,14 +40,26 @@ import { CoreNavigator } from '@services/navigator';
 })
 export class CoreGradesCoursePage implements AfterViewInit, OnDestroy {
 
-    grades: CoreGradesCourseManager;
+    grades!: CoreGradesCourseManager;
     splitViewMode?: CoreSplitViewMode;
 
     @ViewChild(CoreSplitViewComponent) splitView!: CoreSplitViewComponent;
 
     constructor(protected route: ActivatedRoute) {
-        const courseId = CoreNavigator.getRouteNumberParam('courseId', { route })!;
+        let courseId: number;
-        const userId = CoreNavigator.getRouteNumberParam('userId', { route }) ?? CoreSites.getCurrentSiteUserId();
+        let userId: number;
+
+        try {
+            courseId = CoreNavigator.getRequiredRouteNumberParam('courseId', { route });
+            userId = CoreNavigator.getRouteNumberParam('userId', { route }) ?? CoreSites.getCurrentSiteUserId();
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
+
         const useSplitView = route.snapshot.data.useSplitView ?? true;
         const outsideGradesTab = route.snapshot.data.outsideGradesTab ?? false;
 

src/core/features/grades/pages/grade/grade.page.ts

@@ -31,16 +31,24 @@ import { CoreNavigator } from '@services/navigator';
 })
 export class CoreGradesGradePage implements OnInit {
 
-    courseId: number;
+    courseId!: number;
-    userId: number;
+    userId!: number;
-    gradeId: number;
+    gradeId!: number;
     grade?: CoreGradesFormattedRow | null;
     gradeLoaded = false;
 
     constructor() {
-        this.courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+        try {
-        this.gradeId = CoreNavigator.getRouteNumberParam('gradeId')!;
+            this.courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
+            this.gradeId = CoreNavigator.getRequiredRouteNumberParam('gradeId');
             this.userId = CoreNavigator.getRouteNumberParam('userId') ?? CoreSites.getCurrentSiteUserId();
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
     }
 
     /**

src/core/features/user/pages/participants/participants.page.ts

@@ -33,7 +33,7 @@ import { CoreUtils } from '@services/utils/utils';
 })
 export class CoreUserParticipantsPage implements OnInit, AfterViewInit, OnDestroy {
 
-    participants: CoreUserParticipantsManager;
+    participants!: CoreUserParticipantsManager;
     searchQuery: string | null = null;
     searchInProgress = false;
     searchEnabled = false;
@@ -43,7 +43,17 @@ export class CoreUserParticipantsPage implements OnInit, AfterViewInit, OnDestro
     @ViewChild(CoreSplitViewComponent) splitView!: CoreSplitViewComponent;
 
     constructor() {
-        const courseId = CoreNavigator.getRouteNumberParam('courseId')!;
+        let courseId: number;
+
+        try {
+            courseId = CoreNavigator.getRequiredRouteNumberParam('courseId');
+        } catch (error) {
+            CoreDomUtils.showErrorModal(error);
+
+            CoreNavigator.back();
+
+            return;
+        }
 
         this.participants = new CoreUserParticipantsManager(CoreUserParticipantsPage, courseId);
     }

src/core/services/navigator.ts

@@ -30,6 +30,7 @@ import { makeSingleton, NavController, Router } from '@singletons';
 import { CoreScreen } from './screen';
 import { CoreApp } from './app';
 import { CoreSitePlugins } from '@features/siteplugins/services/siteplugins';
+import { CoreError } from '@classes/errors/error';
 
 const DEFAULT_MAIN_MENU_TAB = CoreMainMenuHomeHandlerService.PAGE_NAME;
 
@@ -269,7 +270,7 @@ export class CoreNavigatorService {
 
         const value = route.snapshot.queryParams[name] ?? route.snapshot.params[name];
 
-        if (typeof value != 'undefined') {
+        if (value !== undefined) {
             return value;
         }
 
@@ -300,7 +301,7 @@ export class CoreNavigatorService {
             value = routeOptions.params[name];
         }
 
-        if (typeof value == 'undefined') {
+        if (value === undefined) {
             return;
         }
 
@@ -345,7 +346,7 @@ export class CoreNavigatorService {
     getRouteBooleanParam(name: string, routeOptions: CoreNavigatorCurrentRouteOptions = {}): boolean | undefined {
         const value = this.getRouteParam<string>(name, routeOptions);
 
-        if (typeof value == 'undefined') {
+        if (value === undefined) {
             return value;
         }
 
@@ -360,6 +361,67 @@ export class CoreNavigatorService {
         return Boolean(value);
     }
 
+    /**
+     * Get a parameter for the current route.
+     * Please notice that objects can only be retrieved once. You must call this function only once per page and parameter,
+     * unless there's a new navigation to the page.
+     *
+     * This function will fail if parameter is not found.
+     *
+     * @param name Name of the parameter.
+     * @param routeOptions Optional routeOptions to get the params or route value from. If missing, it will autodetect.
+     * @return Value of the parameter, undefined if not found.
+     */
+    getRequiredRouteParam<T = unknown>(name: string, routeOptions: CoreNavigatorCurrentRouteOptions = {}): T {
+        const value = this.getRouteParam<T>(name, routeOptions);
+
+        if (value === undefined) {
+            throw new CoreError(`Required param '${name}' not found.`);
+        }
+
+        return value;
+    }
+
+    /**
+     * Get a number route param.
+     * Angular router automatically converts numbers to string, this function automatically converts it back to number.
+     *
+     * This function will fail if parameter is not found.
+     *
+     * @param name Name of the parameter.
+     * @param routeOptions Optional routeOptions to get the params or route value from. If missing, it will autodetect.
+     * @return Value of the parameter, undefined if not found.
+     */
+    getRequiredRouteNumberParam(name: string, routeOptions: CoreNavigatorCurrentRouteOptions = {}): number {
+        const value = this.getRouteNumberParam(name, routeOptions);
+
+        if (value === undefined) {
+            throw new CoreError(`Required number param '${name}' not found.`);
+        }
+
+        return value;
+    }
+
+    /**
+     * Get a boolean route param.
+     * Angular router automatically converts booleans to string, this function automatically converts it back to boolean.
+     *
+     * This function will fail if parameter is not found.
+     *
+     * @param name Name of the parameter.
+     * @param routeOptions Optional routeOptions to get the params or route value from. If missing, it will autodetect.
+     * @return Value of the parameter, undefined if not found.
+     */
+    getRequiredRouteBooleanParam(name: string, routeOptions: CoreNavigatorCurrentRouteOptions = {}): boolean {
+        const value = this.getRouteBooleanParam(name, routeOptions);
+
+        if (value === undefined) {
+            throw new CoreError(`Required boolean param '${name}' not found.`);
+        }
+
+        return value;
+    }
+
     /**
      * Navigate back.
      *