MOBILE-2431 tabs: Fix calculate number of core-tabs

src/addon/messages/pages/index/index.ts

@@ -18,6 +18,7 @@ import { CoreEventsProvider } from '@providers/events';
 import { CoreSitesProvider } from '@providers/sites';
 import { AddonMessagesProvider } from '../../providers/messages';
 import { CoreSplitViewComponent } from '@components/split-view/split-view';
+import { CoreTabsComponent } from '@components/tabs/tabs';
 
 /**
  * Page that displays the messages index page.
@@ -29,6 +30,7 @@ import { CoreSplitViewComponent } from '@components/split-view/split-view';
 })
 export class AddonMessagesIndexPage implements OnDestroy {
     @ViewChild(CoreSplitViewComponent) splitviewCtrl: CoreSplitViewComponent;
+    @ViewChild(CoreTabsComponent) tabsComponent: CoreTabsComponent;
 
     protected loadSplitViewObserver: any;
     protected siteId: string;
@@ -61,6 +63,20 @@ export class AddonMessagesIndexPage implements OnDestroy {
         this.splitviewCtrl.push('AddonMessagesDiscussionPage', params);
     }
 
+    /**
+     * User entered the page.
+     */
+    ionViewDidEnter(): void {
+        this.tabsComponent && this.tabsComponent.ionViewDidEnter();
+    }
+
+    /**
+     * User left the page.
+     */
+    ionViewDidLeave(): void {
+        this.tabsComponent && this.tabsComponent.ionViewDidLeave();
+    }
+
     /**
      * Page destroyed.
      */

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

@@ -273,6 +273,24 @@ export class AddonModAssignIndexComponent extends CoreCourseModuleMainActivityCo
         });
     }
 
+    /**
+     * User entered the page that contains the component.
+     */
+    ionViewDidEnter(): void {
+        super.ionViewDidEnter();
+
+        this.submissionComponent && this.submissionComponent.ionViewDidEnter();
+    }
+
+    /**
+     * User left the page that contains the component.
+     */
+    ionViewDidLeave(): void {
+        super.ionViewDidLeave();
+
+        this.submissionComponent && this.submissionComponent.ionViewDidLeave();
+    }
+
     /**
      * Compares sync event data with current data to check if refresh content is needed.
      *

src/addon/mod/assign/components/submission/submission.ts

@@ -313,6 +313,20 @@ export class AddonModAssignSubmissionComponent implements OnInit, OnDestroy {
         return Promise.resolve(false);
     }
 
+    /**
+     * User entered the page that contains the component.
+     */
+    ionViewDidEnter(): void {
+        this.tabs && this.tabs.ionViewDidEnter();
+    }
+
+    /**
+     * User left the page that contains the component.
+     */
+    ionViewDidLeave(): void {
+        this.tabs && this.tabs.ionViewDidLeave();
+    }
+
     /**
      * Invalidate and refresh data.
      *

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

@@ -76,6 +76,20 @@ export class AddonModAssignSubmissionReviewPage implements OnInit {
         return this.submissionComponent.canLeave();
     }
 
+    /**
+     * User entered the page.
+     */
+    ionViewDidEnter(): void {
+        this.submissionComponent && this.submissionComponent.ionViewDidEnter();
+    }
+
+    /**
+     * User left the page.
+     */
+    ionViewDidLeave(): void {
+        this.submissionComponent && this.submissionComponent.ionViewDidLeave();
+    }
+
     /**
      * Get the submission.
      *

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

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-import { Component, Input, Optional, Injector } from '@angular/core';
+import { Component, Input, Optional, Injector, ViewChild } from '@angular/core';
 import { Content, NavController } from 'ionic-angular';
 import { CoreGroupInfo, CoreGroupsProvider } from '@providers/groups';
 import { CoreCourseModuleMainActivityComponent } from '@core/course/classes/main-activity-component';
@@ -21,6 +21,7 @@ import { AddonModFeedbackHelperProvider } from '../../providers/helper';
 import { AddonModFeedbackOfflineProvider } from '../../providers/offline';
 import { AddonModFeedbackSyncProvider } from '../../providers/sync';
 import * as moment from 'moment';
+import { CoreTabsComponent } from '@components/tabs/tabs';
 
 /**
  * Component that displays a feedback index page.
@@ -30,6 +31,8 @@ import * as moment from 'moment';
     templateUrl: 'addon-mod-feedback-index.html',
 })
 export class AddonModFeedbackIndexComponent extends CoreCourseModuleMainActivityComponent {
+    @ViewChild(CoreTabsComponent) tabsComponent: CoreTabsComponent;
+
     @Input() tab = 'overview';
     @Input() group = 0;
 
@@ -348,6 +351,24 @@ export class AddonModFeedbackIndexComponent extends CoreCourseModuleMainActivity
         this.navCtrl.push('AddonModFeedbackFormPage', stateParams);
     }
 
+    /**
+     * User entered the page that contains the component.
+     */
+    ionViewDidEnter(): void {
+        super.ionViewDidEnter();
+
+        this.tabsComponent && this.tabsComponent.ionViewDidEnter();
+    }
+
+    /**
+     * User left the page that contains the component.
+     */
+    ionViewDidLeave(): void {
+        super.ionViewDidLeave();
+
+        this.tabsComponent && this.tabsComponent.ionViewDidLeave();
+    }
+
     /**
      * Function to link implemented features.
      *

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

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-import { Component, Optional, Injector, Input } from '@angular/core';
+import { Component, Optional, Injector, Input, ViewChild } from '@angular/core';
 import { Content, NavController } from 'ionic-angular';
 import { CoreGroupsProvider, CoreGroupInfo } from '@providers/groups';
 import { CoreTimeUtilsProvider } from '@providers/utils/time';
@@ -24,6 +24,7 @@ import { AddonModLessonOfflineProvider } from '../../providers/lesson-offline';
 import { AddonModLessonSyncProvider } from '../../providers/lesson-sync';
 import { AddonModLessonPrefetchHandler } from '../../providers/prefetch-handler';
 import { CoreConstants } from '@core/constants';
+import { CoreTabsComponent } from '@components/tabs/tabs';
 
 /**
  * Component that displays a lesson entry page.
@@ -33,6 +34,8 @@ import { CoreConstants } from '@core/constants';
     templateUrl: 'addon-mod-lesson-index.html',
 })
 export class AddonModLessonIndexComponent extends CoreCourseModuleMainActivityComponent {
+    @ViewChild(CoreTabsComponent) tabsComponent: CoreTabsComponent;
+
     @Input() group: number; // The group to display.
     @Input() action: string; // The "action" to display first.
 
@@ -226,6 +229,8 @@ export class AddonModLessonIndexComponent extends CoreCourseModuleMainActivityCo
     ionViewDidEnter(): void {
         super.ionViewDidEnter();
 
+        this.tabsComponent && this.tabsComponent.ionViewDidEnter();
+
         // Update data when we come back from the player since the status could have changed.
         if (this.hasPlayed) {
             this.hasPlayed = false;
@@ -240,6 +245,8 @@ export class AddonModLessonIndexComponent extends CoreCourseModuleMainActivityCo
     ionViewDidLeave(): void {
         super.ionViewDidLeave();
 
+        this.tabsComponent && this.tabsComponent.ionViewDidLeave();
+
         if (this.navCtrl.getActive().component.name == 'AddonModLessonPlayerPage') {
             this.hasPlayed = true;
         }

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

@@ -735,6 +735,8 @@ export class AddonModWikiIndexComponent extends CoreCourseModuleMainActivityComp
     ionViewDidEnter(): void {
         super.ionViewDidEnter();
 
+        this.tabs && this.tabs.ionViewDidEnter();
+
         if (this.hasEdited) {
             this.hasEdited = false;
             this.showLoadingAndRefresh(true, false);
@@ -747,6 +749,8 @@ export class AddonModWikiIndexComponent extends CoreCourseModuleMainActivityComp
     ionViewDidLeave(): void {
         super.ionViewDidLeave();
 
+        this.tabs && this.tabs.ionViewDidLeave();
+
         if (this.navCtrl.getActive().component.name == 'AddonModWikiEditPage') {
             this.hasEdited = true;
         }

src/components/tabs/tabs.ts

@@ -13,11 +13,12 @@
 // limitations under the License.
 
 import {
-    Component, Input, Output, EventEmitter, OnInit, OnChanges, AfterViewInit, ViewChild, ElementRef,
+    Component, Input, Output, EventEmitter, OnInit, OnChanges, OnDestroy, AfterViewInit, ViewChild, ElementRef,
     SimpleChange
 } from '@angular/core';
 import { CoreTabComponent } from './tab';
 import { Content, Slides } from 'ionic-angular';
+import { CoreDomUtilsProvider } from '@providers/utils/dom';
 
 /**
  * This component displays some tabs that usually share data between them.
@@ -41,7 +42,7 @@ import { Content, Slides } from 'ionic-angular';
     selector: 'core-tabs',
     templateUrl: 'core-tabs.html'
 })
-export class CoreTabsComponent implements OnInit, AfterViewInit, OnChanges {
+export class CoreTabsComponent implements OnInit, AfterViewInit, OnChanges, OnDestroy {
     @Input() selectedIndex = 0; // Index of the tab to select.
     @Input() hideUntil = true; // Determine when should the contents be shown.
     @Input() parentScrollable = false; // Determine if the scroll should be in the parent content or the tab itself.
@@ -66,8 +67,11 @@ export class CoreTabsComponent implements OnInit, AfterViewInit, OnChanges {
     protected tabBarHeight;
     protected tabBarElement: HTMLElement; // Host element.
     protected tabsShown = true;
+    protected resizeFunction;
+    protected isDestroyed = false;
+    protected isCurrentView = true;
 
-    constructor(element: ElementRef, protected content: Content) {
+    constructor(element: ElementRef, protected content: Content, protected domUtils: CoreDomUtilsProvider) {
         this.tabBarElement = element.nativeElement;
     }
 
@@ -83,6 +87,10 @@ export class CoreTabsComponent implements OnInit, AfterViewInit, OnChanges {
      * View has been initialized.
      */
     ngAfterViewInit(): void {
+        if (this.isDestroyed) {
+            return;
+        }
+
         this.afterViewInitTriggered = true;
 
         if (!this.initialized && this.hideUntil) {
@@ -90,10 +98,9 @@ export class CoreTabsComponent implements OnInit, AfterViewInit, OnChanges {
             this.initializeTabs();
         }
 
-        window.addEventListener('resize', () =>  {
+        this.resizeFunction = this.calculateSlides.bind(this);
-            this.calculateMaxSlides();
+
-            this.updateSlides();
+        window.addEventListener('resize', this.resizeFunction);
-        });
     }
 
     /**
@@ -110,6 +117,24 @@ export class CoreTabsComponent implements OnInit, AfterViewInit, OnChanges {
         }
     }
 
+    /**
+     * User entered the page that contains the component.
+     */
+    ionViewDidEnter(): void {
+        this.isCurrentView = true;
+
+        if (this.initialized) {
+            this.calculateSlides();
+        }
+    }
+
+    /**
+     * User left the page that contains the component.
+     */
+    ionViewDidLeave(): void {
+        this.isCurrentView = false;
+    }
+
     /**
      * Add a new tab if it isn't already in the list of tabs.
      *
@@ -120,7 +145,7 @@ export class CoreTabsComponent implements OnInit, AfterViewInit, OnChanges {
         if (this.getIndex(tab) == -1) {
             this.tabs.push(tab);
             this.sortTabs();
-            this.updateSlides();
+            this.calculateSlides();
 
             if (this.initialized && this.tabs.length > 1 && this.tabBarHeight == 0) {
                 // Calculate the tabBarHeight again now that there is more than 1 tab and the bar will be seen.
@@ -132,6 +157,21 @@ export class CoreTabsComponent implements OnInit, AfterViewInit, OnChanges {
         }
     }
 
+    /**
+     * Calculate slides.
+     */
+    calculateSlides(): void {
+        if (!this.isCurrentView || !this.tabsShown) {
+            // Don't calculate if component isn't in current view, the calculations are wrong.
+            return;
+        }
+
+        setTimeout(() => {
+            this.calculateMaxSlides();
+            this.updateSlides();
+        });
+    }
+
     /**
      * Calculate the tab bar height.
      */
@@ -204,9 +244,8 @@ export class CoreTabsComponent implements OnInit, AfterViewInit, OnChanges {
             }
         }
 
-        // Check which arrows should be shown
+        // Check which arrows should be shown.
-        this.calculateMaxSlides();
+        this.calculateSlides();
-        this.updateSlides();
 
         this.initialized = true;
     }
@@ -247,11 +286,16 @@ export class CoreTabsComponent implements OnInit, AfterViewInit, OnChanges {
     }
 
     protected calculateMaxSlides(): void {
-        if (this.slides && this.slides.renderedWidth) {
+        if (this.slides) {
-            this.maxSlides = Math.floor(this.slides.renderedWidth / 120);
+            const width = this.domUtils.getElementWidth(this.slides.getNativeElement()) || this.slides.renderedWidth;
 
-            return;
+            if (width) {
+                this.maxSlides = Math.floor(width / 120);
+
+                return;
+            }
         }
+
         this.maxSlides = 3;
     }
 
@@ -290,6 +334,7 @@ export class CoreTabsComponent implements OnInit, AfterViewInit, OnChanges {
         } else if (!this.tabsShown && e.target.scrollTop < this.tabBarHeight) {
             this.tabBarElement.classList.remove('tabs-hidden');
             this.tabsShown = true;
+            this.calculateSlides();
         }
     }
 
@@ -302,7 +347,7 @@ export class CoreTabsComponent implements OnInit, AfterViewInit, OnChanges {
         const index = this.getIndex(tab);
         this.tabs.splice(index, 1);
 
-        this.updateSlides();
+        this.calculateSlides();
     }
 
     /**
@@ -365,6 +410,17 @@ export class CoreTabsComponent implements OnInit, AfterViewInit, OnChanges {
      * Function to call when the visibility of a tab has changed.
      */
     tabVisibilityChanged(): void {
-       this.updateSlides();
+        this.calculateSlides();
+    }
+
+    /**
+     * Component destroyed.
+     */
+    ngOnDestroy(): void {
+        this.isDestroyed = true;
+
+        if (this.resizeFunction) {
+            window.removeEventListener('resize', this.resizeFunction);
+        }
     }
 }

src/core/course/pages/section/section.ts

@@ -26,6 +26,7 @@ import { CoreCourseModulePrefetchDelegate } from '../../providers/module-prefetc
 import { CoreCourseOptionsDelegate, CoreCourseOptionsHandlerToDisplay } from '../../providers/options-delegate';
 import { CoreCourseFormatComponent } from '../../components/format/format';
 import { CoreCoursesProvider } from '@core/courses/providers/courses';
+import { CoreTabsComponent } from '@components/tabs/tabs';
 
 /**
  * Page that displays the list of courses the user is enrolled in.
@@ -38,6 +39,7 @@ import { CoreCoursesProvider } from '@core/courses/providers/courses';
 export class CoreCourseSectionPage implements OnDestroy {
     @ViewChild(Content) content: Content;
     @ViewChild(CoreCourseFormatComponent) formatComponent: CoreCourseFormatComponent;
+    @ViewChild(CoreTabsComponent) tabsComponent: CoreTabsComponent;
 
     title: string;
     course: any;
@@ -378,6 +380,7 @@ export class CoreCourseSectionPage implements OnDestroy {
      */
     ionViewDidEnter(): void {
         this.formatComponent && this.formatComponent.ionViewDidEnter();
+        this.tabsComponent && this.tabsComponent.ionViewDidEnter();
     }
 
     /**
@@ -385,5 +388,6 @@ export class CoreCourseSectionPage implements OnDestroy {
      */
     ionViewDidLeave(): void {
         this.formatComponent && this.formatComponent.ionViewDidLeave();
+        this.tabsComponent && this.tabsComponent.ionViewDidLeave();
     }
 }

src/core/courses/pages/my-overview/my-overview.ts

@@ -24,6 +24,7 @@ import { CoreCourseHelperProvider } from '@core/course/providers/helper';
 import { CoreCourseOptionsDelegate } from '@core/course/providers/options-delegate';
 import { CoreSiteHomeProvider } from '@core/sitehome/providers/sitehome';
 import * as moment from 'moment';
+import { CoreTabsComponent } from '@components/tabs/tabs';
 
 /**
  * Page that displays My Overview.
@@ -34,6 +35,7 @@ import * as moment from 'moment';
     templateUrl: 'my-overview.html',
 })
 export class CoreCoursesMyOverviewPage implements OnDestroy {
+    @ViewChild(CoreTabsComponent) tabsComponent: CoreTabsComponent;
     @ViewChild('searchbar') searchbar: Searchbar;
 
     firstSelectedTab: number;
@@ -113,6 +115,20 @@ export class CoreCoursesMyOverviewPage implements OnDestroy {
         });
     }
 
+    /**
+     * User entered the page.
+     */
+    ionViewDidEnter(): void {
+        this.tabsComponent && this.tabsComponent.ionViewDidEnter();
+    }
+
+    /**
+     * User left the page.
+     */
+    ionViewDidLeave(): void {
+        this.tabsComponent && this.tabsComponent.ionViewDidLeave();
+    }
+
     /**
      * Fetch the timeline.
      *