MOBILE-2554 core: Create infinite scroll component

src/addon/calendar/pages/list/list.html

@@ -29,12 +29,7 @@
                 </a>
             </ion-list>
 
-            <div *ngIf="canLoadMore" padding>
-                <button ion-button block (click)="fetchEvents()" color="light">{{'core.loadmore' | translate }}</button>
-                <ion-infinite-scroll [enabled]="canLoadMore" (ionInfinite)="$event.waitFor(fetchEvents())">
-                   <ion-infinite-scroll-content></ion-infinite-scroll-content>
-                </ion-infinite-scroll>
-            </div>
+            <core-infinite-loading [enabled]="canLoadMore" (action)="loadMoreEvents($event)"></core-infinite-loading>
         </core-loading>
     </ion-content>
 </core-split-view>

src/addon/calendar/pages/list/list.ts

@@ -179,6 +179,18 @@ export class AddonCalendarListPage implements OnDestroy {
         });
     }
 
+    /**
+     * Function to load more events.
+     *
+     * @param {any} [infiniteComplete] Infinite scroll complete function. Only used from core-infinite-loading.
+     * @return {Promise<any>} Resolved when done.
+     */
+    loadMoreEvents(infiniteComplete?: any): Promise<any> {
+        return this.fetchEvents().finally(() => {
+            infiniteComplete && infiniteComplete();
+        });
+    }
+
     /**
      * Get filtered events.
      *

src/addon/messages/pages/discussion/discussion.html

@@ -15,12 +15,7 @@
 <ion-content class="has-footer">
     <core-loading [hideUntil]="loaded">
         <!-- Load previous messages. -->
-        <div *ngIf="canLoadMore" padding>
-            <ion-infinite-scroll [enabled]="canLoadMore" (ionInfinite)="loadPrevious($event)" position="top">
-               <ion-infinite-scroll-content></ion-infinite-scroll-content>
-            </ion-infinite-scroll>
-            <button ion-button block (click)="loadPrevious()" color="light">{{'core.loadmore' | translate }}</button>
-        </div>
+        <core-infinite-loading [enabled]="canLoadMore" (action)="loadPrevious($event)" position="top"></core-infinite-loading>
         <ion-list class="addon-messages-discussion-container" [attr.aria-live]="polite">
             <ng-container *ngFor="let message of messages; index as index; last as last">
                 <ion-chip *ngIf="showDate(message, messages[index - 1])" class="addon-messages-date" color="light">

src/addon/messages/pages/discussion/discussion.ts

@@ -543,10 +543,10 @@ export class AddonMessagesDiscussionPage implements OnDestroy {
     /**
      * Function to load previous messages.
      *
-     * @param {any} [infiniteScroll] Infinite scroll object.
+     * @param {any} [infiniteComplete] Infinite scroll complete function. Only used from core-infinite-loading.
      * @return {Promise<any>} Resolved when done.
      */
-    loadPrevious(infiniteScroll: any): Promise<any> {
+    loadPrevious(infiniteComplete?: any): Promise<any> {
         // If there is an ongoing fetch, wait for it to finish.
         return this.waitForFetch().finally(() => {
             this.pagesLoaded++;
@@ -555,7 +555,7 @@ export class AddonMessagesDiscussionPage implements OnDestroy {
                 this.pagesLoaded--;
                 this.domUtils.showErrorModalDefault(error, 'addon.messages.errorwhileretrievingmessages', true);
             }).finally(() => {
-                infiniteScroll.complete();
+                infiniteComplete && infiniteComplete();
             });
         });
     }

src/addon/mod/forum/components/index/addon-mod-forum-index.html

@@ -88,12 +88,7 @@
                 </div>
             </core-empty-box>
 
-            <div *ngIf="canLoadMore" padding>
-                <button ion-button block (click)="fetchMoreDiscussions()" color="light">{{'core.loadmore' | translate }}</button>
-                <ion-infinite-scroll [enabled]="canLoadMore" (ionInfinite)="$event.waitFor(fetchMoreDiscussions())">
-                    <ion-infinite-scroll-content></ion-infinite-scroll-content>
-                </ion-infinite-scroll>
-            </div>
+            <core-infinite-loading [enabled]="canLoadMore" (action)="fetchMoreDiscussions($event)"></core-infinite-loading>
         </core-loading>
 
         <ion-fab bottom end *ngIf="forum && forum.cancreatediscussions">

src/addon/mod/forum/components/index/index.ts

@@ -305,13 +305,16 @@ export class AddonModForumIndexComponent extends CoreCourseModuleMainActivityCom
     /**
      * Convenience function to load more forum discussions.
      *
+     * @param {any} [infiniteComplete] Infinite scroll complete function. Only used from core-infinite-loading.
      * @return {Promise<any>} Promise resolved when done.
      */
-    protected fetchMoreDiscussions(): Promise<any> {
+    fetchMoreDiscussions(infiniteComplete?: any): Promise<any> {
         return this.fetchDiscussions(false).catch((message) => {
             this.domUtils.showErrorModalDefault(message, 'addon.mod_forum.errorgetforum', true);
 
             this.canLoadMore = false; // Set to false to prevent infinite calls with infinite-loading.
+        }).finally(() => {
+            infiniteComplete && infiniteComplete();
         });
     }
 

src/addon/mod/glossary/components/index/addon-mod-glossary-index.html

@@ -56,12 +56,7 @@
 
             <core-empty-box *ngIf="!entries.length && !offlineEntries.length" icon="list" [message]="'addon.mod_glossary.noentriesfound' | translate"></core-empty-box>
 
-            <div *ngIf="canLoadMore" padding>
-                <button ion-button block (click)="loadMoreEntries()" color="light">{{'core.loadmore' | translate }}</button>
-                <ion-infinite-scroll [enabled]="canLoadMore" (ionInfinite)="$event.waitFor(loadMoreEntries())">
-                    <ion-infinite-scroll-content></ion-infinite-scroll-content>
-                </ion-infinite-scroll>
-            </div>
+            <core-infinite-loading [enabled]="canLoadMore" (action)="loadMoreEntries($event)"></core-infinite-loading>
         </core-loading>
 
         <ion-fab bottom end *ngIf="canAdd">

src/addon/mod/glossary/components/index/index.ts

@@ -289,11 +289,14 @@ export class AddonModGlossaryIndexComponent extends CoreCourseModuleMainActivity
     /**
      * Convenience function to load more forum discussions.
      *
+     * @param {any} [infiniteComplete] Infinite scroll complete function. Only used from core-infinite-loading.
      * @return {Promise<any>} Promise resolved when done.
      */
-    loadMoreEntries(): Promise<any> {
+    loadMoreEntries(infiniteComplete?: any): Promise<any> {
         return this.fetchEntries(true).catch((error) => {
             this.domUtils.showErrorModalDefault(error, 'addon.mod_glossary.errorloadingentries', true);
+        }).finally(() => {
+            infiniteComplete && infiniteComplete();
         });
     }
 

src/addon/notifications/pages/list/list.html

@@ -32,11 +32,6 @@
             <addon-notifications-actions [contextUrl]="notification.contexturl" [courseId]="notification.courseid"></addon-notifications-actions>
         </ion-card>
         <core-empty-box *ngIf="!notifications || notifications.length <= 0" icon="notifications" [message]="'addon.notifications.therearentnotificationsyet' | translate"></core-empty-box>
-        <div *ngIf="canLoadMore" padding>
-            <button ion-button block (click)="loadMoreNotifications()" color="light">{{'core.loadmore' | translate }}</button>
-            <ion-infinite-scroll [enabled]="canLoadMore" (ionInfinite)="loadMoreNotifications($event)">
-                <ion-infinite-scroll-content></ion-infinite-scroll-content>
-            </ion-infinite-scroll>
-        </div>
+        <core-infinite-loading [enabled]="canLoadMore" (action)="loadMoreNotifications($event)"></core-infinite-loading>
     </core-loading>
 </ion-content>

src/addon/notifications/pages/list/list.ts

@@ -204,11 +204,11 @@ export class AddonNotificationsListPage {
     /**
      * Load more results.
      *
-     * @param {any} infiniteScroll The infinit scroll instance.
+     * @param {any} [infiniteComplete] Infinite scroll complete function. Only used from core-infinite-loading.
      */
-    loadMoreNotifications(infiniteScroll: any): void {
+    loadMoreNotifications(infiniteComplete?: any): void {
         this.fetchNotifications().finally(() => {
-            infiniteScroll.complete();
+            infiniteComplete && infiniteComplete();
         });
     }
 

src/components/components.module.ts

@@ -49,6 +49,7 @@ import { CoreNavigationBarComponent } from './navigation-bar/navigation-bar';
 import { CoreAttachmentsComponent } from './attachments/attachments';
 import { CoreIonTabsComponent } from './ion-tabs/ion-tabs';
 import { CoreIonTabComponent } from './ion-tabs/ion-tab';
+import { CoreInfiniteLoadingComponent } from './infinite-loading/infinite-loading';
 
 @NgModule({
     declarations: [
@@ -83,7 +84,8 @@ import { CoreIonTabComponent } from './ion-tabs/ion-tab';
         CoreNavigationBarComponent,
         CoreAttachmentsComponent,
         CoreIonTabsComponent,
-        CoreIonTabComponent
+        CoreIonTabComponent,
+        CoreInfiniteLoadingComponent
     ],
     entryComponents: [
         CoreContextMenuPopoverComponent,
@@ -125,7 +127,8 @@ import { CoreIonTabComponent } from './ion-tabs/ion-tab';
         CoreNavigationBarComponent,
         CoreAttachmentsComponent,
         CoreIonTabsComponent,
-        CoreIonTabComponent
+        CoreIonTabComponent,
+        CoreInfiniteLoadingComponent
     ]
 })
 export class CoreComponentsModule {}

src/components/infinite-loading/core-infinite-loading.html

@@ -0,0 +1,19 @@
+<div *ngIf="enabled && !loadingMore && position != 'top'" padding-horizontal>
+    <button ion-button block (click)="loadMore()" color="light">
+        {{'core.loadmore' | translate }}
+    </button>
+</div>
+
+<ion-infinite-scroll [enabled]="enabled && !loadingMore" (ionInfinite)="loadMore($event)" [position]="position">
+    <ion-infinite-scroll-content></ion-infinite-scroll-content>
+</ion-infinite-scroll>
+
+<div *ngIf="enabled && !loadingMore && position == 'top'" padding-horizontal>
+    <button ion-button block (click)="loadMore()" color="light">
+        {{'core.loadmore' | translate }}
+    </button>
+</div>
+
+<div *ngIf="loadingMore" padding text-center>
+    <ion-spinner></ion-spinner>
+</div>

src/components/infinite-loading/infinite-loading.ts

@@ -0,0 +1,68 @@
+// (C) Copyright 2015 Martin Dougiamas
+//
+// 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 { Component, Input, Output, EventEmitter } from '@angular/core';
+import { InfiniteScroll } from 'ionic-angular';
+
+/**
+ * Component to show a infinite loading trigger and spinner while more data is being loaded.
+ *
+ * Usage:
+ * <core-infinite-loading [action]="loadingAction" [enabled]="dataLoaded"></core-inifinite-loading>
+ */
+@Component({
+    selector: 'core-infinite-loading',
+    templateUrl: 'core-infinite-loading.html',
+})
+export class CoreInfiniteLoadingComponent {
+    @Input() enabled: boolean;
+    @Input() position = 'bottom';
+    @Output() action: EventEmitter<() => void>; // Will emit an event when triggered.
+
+    loadingMore = false;   // Hide button and avoid loading more.
+
+    protected infiniteScroll: InfiniteScroll;
+
+    constructor() {
+        this.action = new EventEmitter();
+    }
+
+    /**
+     * Load More items calling the action provided.
+     *
+     * @param {InfiniteScroll} [infiniteScroll] Infinite scroll object only if triggered from the scroll.
+     */
+    loadMore(infiniteScroll?: InfiniteScroll): void {
+        if (this.loadingMore) {
+            return;
+        }
+
+        if (infiniteScroll) {
+            this.infiniteScroll = infiniteScroll;
+        }
+        this.loadingMore = true;
+
+        this.action.emit(this.complete.bind(this));
+    }
+
+    /**
+     * Complete loading.
+     */
+    complete(): void {
+        this.loadingMore = false;
+        this.infiniteScroll && this.infiniteScroll.complete();
+        this.infiniteScroll = undefined;
+    }
+
+}

src/core/course/components/format/core-course-format.html

@@ -51,12 +51,7 @@
                 </ng-container>
             </core-dynamic-component>
 
-            <div *ngIf="canLoadMore" padding>
-                <button ion-button block (click)="showMoreActivities()" color="light">{{'core.loadmore' | translate }}</button>
-                <ion-infinite-scroll [enabled]="canLoadMore" (ionInfinite)="$event.waitFor(showMoreActivities())">
-                   <ion-infinite-scroll-content></ion-infinite-scroll-content>
-                </ion-infinite-scroll>
-            </div>
+            <core-infinite-loading [enabled]="canLoadMore" (action)="showMoreActivities($event)"></core-infinite-loading>
         </div>
     </core-loading>
     <ion-buttons padding end class="core-course-section-nav-buttons" *ngIf="displaySectionSelector && sections && sections.length">

src/core/course/components/format/format.ts

@@ -373,9 +373,9 @@ export class CoreCourseFormatComponent implements OnInit, OnChanges, OnDestroy {
     /**
      * Show more activities (only used when showing all the sections at the same time).
      *
-     * @return {Promise<void>} Resolved when done to change infinite loading status.
+     * @param {any} [infiniteComplete] Infinite scroll complete function. Only used from core-infinite-loading.
      */
-    showMoreActivities(): Promise<void> {
+    showMoreActivities(infiniteComplete?: any): void {
         this.canLoadMore = false;
 
         let modulesLoaded = 0,
@@ -399,7 +399,7 @@ export class CoreCourseFormatComponent implements OnInit, OnChanges, OnDestroy {
             // Check if any of the following sections have any content.
             let thereAreMore = false;
             for (i++; i < this.sections.length; i++) {
-                if (this.sections[i].hasContent && this.sections[i].modules) {
+                if (this.sections[i].hasContent && this.sections[i].modules && this.sections[i].modules.length > 0) {
                     thereAreMore = true;
                     break;
                 }
@@ -407,7 +407,7 @@ export class CoreCourseFormatComponent implements OnInit, OnChanges, OnDestroy {
             this.canLoadMore = thereAreMore;
         }
 
-        return Promise.resolve();
+        infiniteComplete && infiniteComplete();
     }
 
     /**

src/core/course/providers/default-format.ts

@@ -16,7 +16,6 @@ import { Injectable } from '@angular/core';
 import { NavController } from 'ionic-angular';
 import { CoreCoursesProvider } from '@core/courses/providers/courses';
 import { CoreCourseFormatHandler } from './format-delegate';
-import { CoreCourseProvider } from './course';
 
 /**
  * Default handler used when the course format doesn't have a specific implementation.

src/core/courses/pages/search/search.html

@@ -10,12 +10,7 @@
         <ion-item-divider color="light">{{ 'core.courses.totalcoursesearchresults' | translate:{$a: total} }}</ion-item-divider>
         <core-empty-box *ngIf="total == 0" icon="search" [message]="'core.courses.nosearchresults' | translate"></core-empty-box>
         <core-courses-course-list-item *ngFor="let course of courses" [course]="course"></core-courses-course-list-item>
-        <div *ngIf="canLoadMore" padding>
-            <button ion-button block (click)="loadMoreResults()" color="light">{{'core.loadmore' | translate }}</button>
-            <ion-infinite-scroll [enabled]="canLoadMore" (ionInfinite)="loadMoreResults($event)">
-                <ion-infinite-scroll-content></ion-infinite-scroll-content>
-            </ion-infinite-scroll>
-        </div>
+        <core-infinite-loading [enabled]="canLoadMore" (action)="loadMoreResults($event)"></core-infinite-loading>
     </div>
 </ion-content>
 

src/core/courses/pages/search/search.ts

@@ -54,11 +54,11 @@ export class CoreCoursesSearchPage {
     /**
      * Load more results.
      *
-     * @param {any} infiniteScroll The infinit scroll instance.
+     * @param {any} [infiniteComplete] Infinite scroll complete function. Only used from core-infinite-loading.
      */
-    loadMoreResults(infiniteScroll: any): void {
+    loadMoreResults(infiniteComplete?: any): void {
         this.searchCourses().finally(() => {
-            infiniteScroll.complete();
+            infiniteComplete && infiniteComplete();
         });
     }
 

src/core/user/components/participants/core-user-participants.html

@@ -16,13 +16,7 @@
                     <p *ngIf="participant.lastaccess"><strong>{{ 'core.lastaccess' | translate }}: </strong>{{ participant.lastaccess * 1000 | coreFormatDate:"dfmediumdate"}}</p>
                 </a>
             </ion-list>
-
-            <div *ngIf="canLoadMore" padding>
-                <button ion-button block (click)="fetchData()" color="light">{{'core.loadmore' | translate }}</button>
-                <ion-infinite-scroll [enabled]="canLoadMore" (ionInfinite)="$event.waitFor(fetchData())">
-                   <ion-infinite-scroll-content></ion-infinite-scroll-content>
-                </ion-infinite-scroll>
-            </div>
+            <core-infinite-loading [enabled]="canLoadMore" (action)="loadMoreData($event)"></core-infinite-loading>
         </core-loading>
     </ion-content>
 </core-split-view>

src/core/user/components/participants/participants.ts

@@ -82,6 +82,18 @@ export class CoreUserParticipantsComponent implements OnInit {
         });
     }
 
+    /**
+     * Function to load more data.
+     *
+     * @param {any} [infiniteComplete] Infinite scroll complete function. Only used from core-infinite-loading.
+     * @return {Promise<any>} Resolved when done.
+     */
+    loadMoreData(infiniteComplete?: any): Promise<any> {
+        return this.fetchData().finally(() => {
+            infiniteComplete && infiniteComplete();
+        });
+    }
+
     /**
      * Refresh data.
      *