Extract list items management from settings

src/core/classes/page-items-list-manager.ts

@@ -0,0 +1,202 @@
+// (C) Copyright 2015 Moodle Pty Ltd.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import { ActivatedRouteSnapshot, Params } from '@angular/router';
+import { Subscription } from 'rxjs';
+
+import { CoreSplitViewComponent } from '@components/split-view/split-view';
+import { CoreNavigator } from '@services/navigator';
+import { CoreScreen } from '@services/screen';
+import { CoreUtils } from '@services/utils/utils';
+
+/**
+ * Helper class to manage the state and routing of a list of items in a page, for example on pages using a split view.
+ */
+export abstract class CorePageItemsListManager<Item> {
+
+    protected itemsList: Item[] | null = null;
+    protected itemsMap: Record<string, Item> | null = null;
+    protected selectedItem: Item | null = null;
+    protected pageComponent: unknown;
+    protected splitView?: CoreSplitViewComponent;
+    protected splitViewOutletSubscription?: Subscription;
+
+    constructor(pageComponent: unknown) {
+        this.pageComponent = pageComponent;
+    }
+
+    get items(): Item[] {
+        return this.itemsList || [];
+    }
+
+    get loaded(): boolean {
+        return this.itemsMap !== null;
+    }
+
+    get empty(): boolean {
+        return this.itemsList === null || this.itemsList.length === 0;
+    }
+
+    /**
+     * Process page started operations.
+     */
+    async start(): Promise<void> {
+        // Calculate current selected item.
+        const route = CoreNavigator.instance.getCurrentRoute({ pageComponent: this.pageComponent });
+        if (route !== null && route.firstChild) {
+            this.updateSelectedItem(route.firstChild.snapshot);
+        }
+
+        // Select default item if none is selected on a non-mobile layout.
+        if (!CoreScreen.instance.isMobile && this.selectedItem === null) {
+            const defaultItem = this.getDefaultItem();
+
+            if (defaultItem) {
+                this.select(defaultItem);
+            }
+        }
+
+        // Log activity.
+        await CoreUtils.instance.ignoreErrors(this.logActivity());
+    }
+
+    /**
+     * Process page destroyed operations.
+     */
+    destroy(): void {
+        this.splitViewOutletSubscription?.unsubscribe();
+    }
+
+    /**
+     * Watch a split view outlet to keep track of the selected item.
+     *
+     * @param splitView Split view component.
+     */
+    watchSplitViewOutlet(splitView: CoreSplitViewComponent): void {
+        this.splitView = splitView;
+        this.splitViewOutletSubscription = splitView.outletRouteObservable.subscribe(route => this.updateSelectedItem(route));
+
+        this.updateSelectedItem(splitView.outletRoute);
+    }
+
+    // @todo Implement watchResize.
+
+    /**
+     * Check whether the given item is selected or not.
+     *
+     * @param item Item.
+     * @return Whether the given item is selected.
+     */
+    isSelected(item: Item): boolean {
+        return this.selectedItem === item;
+    }
+
+    /**
+     * Select an item.
+     *
+     * @param item Item.
+     */
+    async select(item: Item): Promise<void> {
+        // Get current route in the page.
+        const route = CoreNavigator.instance.getCurrentRoute({ pageComponent: this.pageComponent });
+
+        if (route === null) {
+            return;
+        }
+
+        // If this item is already selected, do nothing.
+        const itemPath = this.getItemPath(item);
+
+        if (route.firstChild?.routeConfig?.path === itemPath) {
+            return;
+        }
+
+        // Navigate to item.
+        const path = route.firstChild ? `../${itemPath}` : itemPath;
+        const params = this.getItemQueryParams(item);
+
+        await CoreNavigator.instance.navigate(path, { params });
+    }
+
+    /**
+     * Set the list of items.
+     *
+     * @param items Items.
+     */
+    setItems(items: Item[]): void {
+        this.itemsList = items.slice(0);
+        this.itemsMap = items.reduce((map, item) => {
+            map[this.getItemPath(item)] = item;
+
+            return map;
+        }, {});
+
+        this.updateSelectedItem(this.splitView?.outletRoute);
+    }
+
+    /**
+     * Log activity when the page starts.
+     */
+    protected async logActivity(): Promise<void> {
+        //
+    }
+
+    /**
+     * Update the selected item given the current route.
+     *
+     * @param route Current route.
+     */
+    protected updateSelectedItem(route?: ActivatedRouteSnapshot | null): void {
+        const selectedItemPath = route ? this.getSelectedItemPath(route) : null;
+
+        this.selectedItem = selectedItemPath
+            ? this.itemsMap?.[selectedItemPath] ?? null
+            : null;
+    }
+
+    /**
+     * Get the item that should be selected by default.
+     */
+    protected getDefaultItem(): Item | null {
+        return this.itemsList?.[0] || null;
+    }
+
+    /**
+     * Get the query parameters to use when navigating to an item page.
+     *
+     * @param item Item.
+     * @return Query parameters to use when navigating to the item page.
+     */
+    // eslint-disable-next-line @typescript-eslint/no-unused-vars
+    protected getItemQueryParams(item: Item): Params {
+        return {};
+    }
+
+    /**
+     * Get the path to use when navigating to an item page.
+     *
+     * @param item Item.
+     * @return Path to use when navigating to the item page.
+     */
+    protected abstract getItemPath(item: Item): string;
+
+    /**
+     * Get the path of the selected item given the current route.
+     *
+     * @param route Current route.
+     * @return Path of the selected item in the given route.
+     */
+    protected abstract getSelectedItemPath(route: ActivatedRouteSnapshot): string | null;
+
+}

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

@@ -13,9 +13,10 @@
 // limitations under the License.
 
 import { AfterViewInit, Component, ElementRef, HostBinding, Input, OnDestroy, ViewChild } from '@angular/core';
+import { ActivatedRouteSnapshot } from '@angular/router';
 import { IonRouterOutlet } from '@ionic/angular';
 import { CoreScreen } from '@services/screen';
-import { Subscription } from 'rxjs';
+import { BehaviorSubject, Observable, Subscription } from 'rxjs';
 
 enum CoreSplitViewMode {
     MenuOnly = 'menu-only', // Hides content.
@@ -35,18 +36,33 @@ export class CoreSplitViewComponent implements AfterViewInit, OnDestroy {
     @Input() placeholderText = 'core.emptysplit';
     isNested = false;
 
+    private outletRouteSubject: BehaviorSubject<ActivatedRouteSnapshot | null> = new BehaviorSubject(null);
     private subscriptions?: Subscription[];
 
     constructor(private element: ElementRef<HTMLElement>) {}
 
+    get outletRoute(): ActivatedRouteSnapshot | null {
+        return this.outletRouteSubject.value;
+    }
+
+    get outletRouteObservable(): Observable<ActivatedRouteSnapshot | null> {
+        return this.outletRouteSubject.asObservable();
+    }
+
     /**
      * @inheritdoc
      */
     ngAfterViewInit(): void {
         this.isNested = !!this.element.nativeElement.parentElement?.closest('core-split-view');
         this.subscriptions = [
-            this.outlet.activateEvents.subscribe(() => this.updateClasses()),
-            this.outlet.deactivateEvents.subscribe(() => this.updateClasses()),
+            this.outlet.activateEvents.subscribe(() => {
+                this.updateClasses();
+                this.outletRouteSubject.next(this.outlet.activatedRoute.snapshot);
+            }),
+            this.outlet.deactivateEvents.subscribe(() => {
+                this.updateClasses();
+                this.outletRouteSubject.next(null);
+            }),
             CoreScreen.instance.layoutObservable.subscribe(() => this.updateClasses()),
         ];
 

src/core/features/settings/pages/index/index.html

@@ -11,11 +11,11 @@
     <core-split-view>
         <ion-list>
             <ion-item
-                *ngFor="let section of sections"
-                [class.core-selected-item]="section.name === activeSection"
+                *ngFor="let section of sections.items"
+                [class.core-selected-item]="sections.isSelected(section)"
                 button
                 detail
-                (click)="openSection(section)"
+                (click)="sections.select(section)"
             >
                 <ion-icon [name]="section.icon" slot="start"></ion-icon>
                 <ion-label>{{ 'core.settings.' + section.name | translate }}</ion-label>

src/core/features/settings/pages/index/index.ts

@@ -12,83 +12,57 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-import { Component, OnDestroy, OnInit } from '@angular/core';
-import { Subscription } from 'rxjs';
-
-import { CoreNavigator } from '@services/navigator';
-import { CoreScreen } from '@services/screen';
+import { AfterViewInit, Component, OnDestroy, ViewChild } from '@angular/core';
 import { CoreSettingsConstants, CoreSettingsSection } from '@features/settings/constants';
+import { CorePageItemsListManager } from '@classes/page-items-list-manager';
+import { ActivatedRouteSnapshot } from '@angular/router';
+import { CoreSplitViewComponent } from '@components/split-view/split-view';
 
 @Component({
     selector: 'page-core-settings-index',
     templateUrl: 'index.html',
 })
-export class CoreSettingsIndexPage implements OnInit, OnDestroy {
+export class CoreSettingsIndexPage implements AfterViewInit, OnDestroy {
 
-    sections = CoreSettingsConstants.SECTIONS;
-    activeSection?: string;
-    layoutSubscription?: Subscription;
+    sections: CoreSettingsSectionsManager = new CoreSettingsSectionsManager(CoreSettingsIndexPage);
+
+    @ViewChild(CoreSplitViewComponent) splitView!: CoreSplitViewComponent;
 
     /**
      * @inheritdoc
      */
-    ngOnInit(): void {
-        this.layoutSubscription = CoreScreen.instance.layoutObservable.subscribe(() => this.updateActiveSection());
-    }
-
-    /**
-     * @inheritdoc
-     */
-    ionViewWillEnter(): void {
-        this.updateActiveSection();
+    ngAfterViewInit(): void {
+        this.sections.setItems(CoreSettingsConstants.SECTIONS);
+        this.sections.watchSplitViewOutlet(this.splitView);
+        this.sections.start();
     }
 
     /**
      * @inheritdoc
      */
     ngOnDestroy(): void {
-        this.layoutSubscription?.unsubscribe();
-    }
-
-    /**
-     * Open a section page.
-     *
-     * @param section Section to open.
-     */
-    openSection(section: CoreSettingsSection): void {
-        const path = this.activeSection ? `../${section.path}` : section.path;
-
-        CoreNavigator.instance.navigate(path);
-
-        this.updateActiveSection(section.name);
-    }
-
-    /**
-     * Update active section.
-     *
-     * @param activeSection Active section.
-     */
-    private updateActiveSection(activeSection?: string): void {
-        if (CoreScreen.instance.isMobile) {
-            delete this.activeSection;
-
-            return;
-        }
-
-        this.activeSection = activeSection ?? this.guessActiveSection();
-    }
-
-    /**
-     * Guess active section looking at the current route.
-     *
-     * @return Active section.
-     */
-    private guessActiveSection(): string | undefined {
-        const activeSection = this.sections.find(
-            section => CoreNavigator.instance.isCurrent(`**/settings/${section.path}`),
-        );
-
-        return activeSection?.name;
+        this.sections.destroy();
+    }
+
+}
+
+/**
+ * Helper class to manage sections.
+ */
+class CoreSettingsSectionsManager extends CorePageItemsListManager<CoreSettingsSection> {
+
+    /**
+     * @inheritdoc
+     */
+    protected getItemPath(section: CoreSettingsSection): string {
+        return section.path;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    protected getSelectedItemPath(route: ActivatedRouteSnapshot): string | null {
+        return route.parent?.routeConfig?.path ?? null;
     }
 
 }

src/core/services/navigator.ts

@@ -50,6 +50,14 @@ export type CoreNavigationOptions = {
     reset?: boolean;
 };
 
+/**
+ * Options for CoreNavigatorService#getCurrentRoute method.
+ */
+type GetCurrentRouteOptions = Partial<{
+    parentRoute: ActivatedRoute;
+    pageComponent: unknown;
+}>;
+
 /**
  * Service to provide some helper functions regarding navigation.
  */
@@ -310,13 +318,26 @@ export class CoreNavigatorService {
     /**
      * Get current activated route.
      *
-     * @param route Parent route.
+     * @param options
+     *     - parent: Parent route, if this isn't provided the current active route will be used.
+     *     - pageComponent: Page component of the route to find, if this isn't provided the deepest route in the hierarchy
+     *                      will be returned.
      * @return Current activated route.
      */
-    protected getCurrentRoute(route?: ActivatedRoute): ActivatedRoute {
-        route = route ?? Router.instance.routerState.root;
+    getCurrentRoute(): ActivatedRoute;
+    getCurrentRoute(options: GetCurrentRouteOptions): ActivatedRoute | null;
+    getCurrentRoute({ parentRoute, pageComponent }: GetCurrentRouteOptions = {}): ActivatedRoute | null {
+        parentRoute = parentRoute ?? Router.instance.routerState.root;
 
-        return route.firstChild ? this.getCurrentRoute(route.firstChild) : route;
+        if (pageComponent && parentRoute.component === pageComponent) {
+            return parentRoute;
+        }
+
+        if (parentRoute.firstChild) {
+            return this.getCurrentRoute({ parentRoute: parentRoute.firstChild, pageComponent });
+        }
+
+        return pageComponent ? null : parentRoute;
     }
 
     /**