MOBILE-3927 book: Add swipe to book

src/addons/mod/book/components/index/addon-mod-book-index.html

@@ -40,15 +40,18 @@
             previousTranslate="addon.mod_book.navprevtitle" nextTranslate="addon.mod_book.navnexttitle" (action)="changeChapter($event.id)">
         </core-navigation-bar>
 
+        <ion-slides (ionSlideWillChange)="slideChanged()" [options]="slidesOpts">
+            <ion-slide *ngFor="let chapter of loadedChapters">
                 <div class="ion-padding">
-            <core-format-text [component]="component" [componentId]="componentId" [text]="chapterContent" contextLevel="module"
+                    <core-format-text [component]="component" [componentId]="componentId" [text]="chapter.content" contextLevel="module"
                         [contextInstanceId]="module.id" [courseId]="courseId"></core-format-text>
-
+                    <div class="ion-margin-top" *ngIf="tagsEnabled && chapter.tags?.length > 0">
-            <div class="ion-margin-top" *ngIf="tagsEnabled && tags?.length > 0">
                         <strong>{{ 'core.tag.tags' | translate }}: </strong>
-                <core-tag-list [tags]="tags"></core-tag-list>
+                        <core-tag-list [tags]="chapter.tags"></core-tag-list>
                     </div>
                 </div>
+            </ion-slide>
+        </ion-slides>
     </div>
 
 </core-loading>

src/addons/mod/book/components/index/index.scss

@@ -0,0 +1,9 @@
+:host {
+    ion-slide {
+        display: block;
+        font-size: inherit;
+        justify-content: start;
+        align-items: start;
+        text-align: start;
+    }
+}

src/addons/mod/book/components/index/index.ts

@@ -12,8 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-import { Component, Optional, Input, OnInit } from '@angular/core';
+import { Component, Optional, Input, OnInit, ViewChild, ElementRef } from '@angular/core';
-import { IonContent } from '@ionic/angular';
+import { IonContent, IonSlides } from '@ionic/angular';
 import { CoreCourseModuleMainResourceComponent } from '@features/course/classes/main-resource-component';
 import {
     AddonModBookProvider,
@@ -31,6 +31,8 @@ import { CoreCourse } from '@features/course/services/course';
 import { AddonModBookTocComponent } from '../toc/toc';
 import { CoreConstants } from '@/core/constants';
 import { CoreNavigationBarItem } from '@components/navigation-bar/navigation-bar';
+import { CoreError } from '@classes/errors/error';
+import { Translate } from '@singletons';
 
 /**
  * Component that displays a book.
@@ -38,30 +40,43 @@ import { CoreNavigationBarItem } from '@components/navigation-bar/navigation-bar
 @Component({
     selector: 'addon-mod-book-index',
     templateUrl: 'addon-mod-book-index.html',
+    styleUrls: ['index.scss'],
 })
 export class AddonModBookIndexComponent extends CoreCourseModuleMainResourceComponent implements OnInit {
 
+    @ViewChild(IonSlides) slides?: IonSlides;
+
     @Input() initialChapterId?: number; // The initial chapter ID to load.
 
     component = AddonModBookProvider.COMPONENT;
-    chapterContent?: string;
+    loadedChapters: LoadedChapter[] = [];
+    previousChapter?: AddonModBookTocChapter;
+    nextChapter?: AddonModBookTocChapter;
     tagsEnabled = false;
     warning = '';
     tags?: CoreTagItem[];
     displayNavBar = true;
     navigationItems: CoreNavigationBarItem<AddonModBookTocChapter>[] = [];
     displayTitlesInNavBar = false;
+    slidesOpts = {
+        initialSlide: 0,
+        autoHeight: true,
+    };
 
     protected chapters: AddonModBookTocChapter[] = [];
     protected currentChapter?: number;
     protected book?: AddonModBookBookWSData;
     protected contentsMap: AddonModBookContentsMap = {};
+    protected element: HTMLElement;
 
     constructor(
+        elementRef: ElementRef,
         protected content?: IonContent,
         @Optional() courseContentsPage?: CoreCourseContentsPage,
     ) {
         super('AddonModBookIndexComponent', courseContentsPage);
+
+        this.element = elementRef.nativeElement;
     }
 
     /**
@@ -102,10 +117,13 @@ export class AddonModBookIndexComponent extends CoreCourseModuleMainResourceComp
      * @return Promise resolved when done.
      */
     changeChapter(chapterId: number): void {
-        if (chapterId && chapterId != this.currentChapter) {
+        if (!chapterId || chapterId === this.currentChapter) {
-            this.loaded = false;
+            return;
-            this.refreshIcon = CoreConstants.ICON_LOADING;
+        }
-            this.loadChapter(chapterId, true);
+
+        const index = this.loadedChapters.findIndex(chapter => chapter.id === chapterId);
+        if (index > -1) {
+            this.slides?.slideTo(index);
         }
     }
 
@@ -138,10 +156,11 @@ export class AddonModBookIndexComponent extends CoreCourseModuleMainResourceComp
 
             if (typeof this.currentChapter == 'undefined' && typeof this.initialChapterId != 'undefined' && this.chapters) {
                 // Initial chapter set. Validate that the chapter exists.
-                const chapter = this.chapters.find((chapter) => chapter.id == this.initialChapterId);
+                const index = this.chapters.findIndex((chapter) => chapter.id == this.initialChapterId);
 
-                if (chapter) {
+                if (index >= 0) {
                     this.currentChapter = this.initialChapterId;
+                    this.slidesOpts.initialSlide = index;
                 }
             }
 
@@ -154,14 +173,12 @@ export class AddonModBookIndexComponent extends CoreCourseModuleMainResourceComp
                 return;
             }
 
+            await this.loadChapters();
+
             // Show chapter.
-            try {
+            await this.viewChapter(this.currentChapter, refresh);
-                await this.loadChapter(this.currentChapter, refresh);
 
             this.warning = downloadResult?.failed ? this.getErrorDownloadingSomeFilesMessage(downloadResult.error!) : '';
-            } catch {
-                // Ignore errors, they're handled inside the loadChapter function.
-            }
         } finally {
             // Pass false because downloadResourceIfNeeded already invalidates and refresh data if refresh=true.
             this.fillContextMenu(false);
@@ -184,28 +201,58 @@ export class AddonModBookIndexComponent extends CoreCourseModuleMainResourceComp
     }
 
     /**
-     * Load a book chapter.
+     * Load book chapters.
+     *
+     * @return Promise resolved when done.
+     */
+    protected async loadChapters(): Promise<void> {
+        try {
+            const newChapters = await Promise.all(this.chapters.map(async (chapter) => {
+                const content = await AddonModBook.getChapterContent(this.contentsMap, chapter.id, this.module.id);
+
+                return {
+                    id: chapter.id,
+                    content,
+                    tags: this.tagsEnabled ? this.contentsMap[chapter.id].tags : [],
+                };
+            }));
+
+            let newIndex = -1;
+            if (this.loadedChapters.length && newChapters.length != this.loadedChapters.length) {
+                // Number of chapters has changed. Search the chapter to display, otherwise it could change automatically.
+                newIndex = this.chapters.findIndex((chapter) => chapter.id === this.currentChapter);
+            }
+
+            this.loadedChapters = newChapters;
+
+            if (newIndex > -1) {
+                this.slides?.slideTo(newIndex, 0, false);
+            }
+        } catch (exception) {
+            const error = exception ?? new CoreError(Translate.instant('addon.mod_book.errorchapter'));
+            if (!error.message) {
+                error.message = Translate.instant('addon.mod_book.errorchapter');
+            }
+
+            throw error;
+        }
+    }
+
+    /**
+     * View a book chapter.
      *
      * @param chapterId Chapter to load.
      * @param logChapterId Whether chapter ID should be passed to the log view function.
      * @return Promise resolved when done.
      */
-    protected async loadChapter(chapterId: number, logChapterId: boolean): Promise<void> {
+    protected async viewChapter(chapterId: number, logChapterId: boolean): Promise<void> {
         this.currentChapter = chapterId;
-        this.content?.scrollToTop();
-
-        try {
-            const content = await AddonModBook.getChapterContent(this.contentsMap, chapterId, this.module.id);
-
-            this.tags = this.tagsEnabled ? this.contentsMap[this.currentChapter].tags : [];
-
-            this.chapterContent = content;
 
         if (this.displayNavBar) {
             this.navigationItems = this.getNavigationItems(chapterId);
         }
 
-            // Chapter loaded, log view. We don't return the promise because we don't want to block the user for this.
+        // Chapter loaded, log view.
         await CoreUtils.ignoreErrors(AddonModBook.logView(
             this.module.instance!,
             logChapterId ? chapterId : undefined,
@@ -219,14 +266,29 @@ export class AddonModBookIndexComponent extends CoreCourseModuleMainResourceComp
         if (isLastChapter) {
             CoreCourse.checkModuleCompletion(this.courseId, this.module.completiondata);
         }
-        } catch (error) {
-            CoreDomUtils.showErrorModalDefault(error, 'addon.mod_book.errorchapter', true);
-
-            throw error;
-        } finally {
-            this.loaded = true;
-            this.refreshIcon = CoreConstants.ICON_REFRESH;
     }
+
+    /**
+     * Slide has changed.
+     *
+     * @return Promise resolved when done.
+     */
+    async slideChanged(): Promise<void> {
+        if (!this.slides) {
+            return;
+        }
+
+        const scrollElement = await this.content?.getScrollElement();
+        const container = this.element.querySelector<HTMLElement>('.addon-mod_book-container');
+
+        if (container && (!scrollElement || CoreDomUtils.isElementOutsideOfScreen(scrollElement, container, 'top'))) {
+            // Scroll to top.
+            container.scrollIntoView({ behavior: 'smooth' });
+        }
+
+        const index = await this.slides.getActiveIndex();
+
+        this.viewChapter(this.loadedChapters[index].id, true);
     }
 
     /**
@@ -245,3 +307,9 @@ export class AddonModBookIndexComponent extends CoreCourseModuleMainResourceComp
     }
 
 }
+
+type LoadedChapter = {
+    id: number;
+    content: string;
+    tags?: CoreTagItem[];
+};

src/core/services/utils/dom.ts

@@ -769,21 +769,29 @@ export class CoreDomUtilsProvider {
      *
      * @param scrollEl The element that must be scrolled.
      * @param element DOM element to check.
+     * @param point The point of the element to check.
      * @return Whether the element is outside of the viewport.
      */
-    isElementOutsideOfScreen(scrollEl: HTMLElement, element: HTMLElement): boolean {
+    isElementOutsideOfScreen(scrollEl: HTMLElement, element: HTMLElement, point: 'top' | 'mid' | 'bottom' = 'mid'): boolean {
         const elementRect = element.getBoundingClientRect();
 
         if (!elementRect) {
             return false;
         }
 
-        const elementMidPoint = Math.round((elementRect.bottom + elementRect.top) / 2);
+        let elementPoint: number;
+        if (point === 'top') {
+            elementPoint = elementRect.top;
+        } else if (point === 'bottom') {
+            elementPoint = elementRect.bottom;
+        } else {
+            elementPoint = Math.round((elementRect.bottom + elementRect.top) / 2);
+        }
 
         const scrollElRect = scrollEl.getBoundingClientRect();
         const scrollTopPos = scrollElRect?.top || 0;
 
-        return elementMidPoint > window.innerHeight || elementMidPoint < scrollTopPos;
+        return elementPoint > window.innerHeight || elementPoint < scrollTopPos;
     }
 
     /**