From 456784620982e091354e66c92db42f91fe4c7d76 Mon Sep 17 00:00:00 2001
From: Noel De Martin <noel@moodle.com>
Date: Tue, 15 Jun 2021 18:28:20 +0200
Subject: [PATCH] MOBILE-3320 tabs: Call navigation hooks

---
 .../components/tabs-outlet/tabs-outlet.ts     | 43 +++++++++++++++++--
 1 file changed, 39 insertions(+), 4 deletions(-)

diff --git a/src/core/components/tabs-outlet/tabs-outlet.ts b/src/core/components/tabs-outlet/tabs-outlet.ts
index 2ccf498e3..1783496b4 100644
--- a/src/core/components/tabs-outlet/tabs-outlet.ts
+++ b/src/core/components/tabs-outlet/tabs-outlet.ts
@@ -23,7 +23,7 @@ import {
     ElementRef,
     SimpleChange,
 } from '@angular/core';
-import { IonTabs } from '@ionic/angular';
+import { IonTabs, ViewDidEnter, ViewDidLeave } from '@ionic/angular';
 import { Subscription } from 'rxjs';
 
 import { CoreUtils } from '@services/utils/utils';
@@ -65,10 +65,11 @@ export class CoreTabsOutletComponent extends CoreTabsBaseComponent<CoreTabsOutle
     @ViewChild(IonTabs) protected ionTabs?: IonTabs;
 
     protected stackEventsSubscription?: Subscription;
+    protected outletActivatedSubscription?: Subscription;
+    protected lastActiveComponent?: Partial<ViewDidLeave>;
+    protected existsInNavigationStack = false;
 
-    constructor(
-        element: ElementRef,
-    ) {
+    constructor(element: ElementRef) {
         super(element);
     }
 
@@ -110,6 +111,9 @@ export class CoreTabsOutletComponent extends CoreTabsBaseComponent<CoreTabsOutle
                 this.showHideTabs(scrollElement.scrollTop, scrollElement);
             }
         });
+        this.outletActivatedSubscription = this.ionTabs?.outlet.activateEvents.subscribe(() => {
+            this.lastActiveComponent = this.ionTabs?.outlet.component;
+        });
     }
 
     /**
@@ -127,6 +131,35 @@ export class CoreTabsOutletComponent extends CoreTabsBaseComponent<CoreTabsOutle
         super.ngOnChanges(changes);
     }
 
+    /**
+     * @inheritdoc
+     */
+    ionViewDidEnter(): void {
+        super.ionViewDidEnter();
+
+        // The `ionViewDidEnter` method is not called on nested outlets unless the parent page is leaving the navigation stack,
+        // that's why we need to call it manually if the page that is entering already existed in the stack (meaning that it is
+        // entering in response to a back navigation from the page on top).
+        if (this.existsInNavigationStack && this.ionTabs?.outlet.isActivated) {
+            (this.ionTabs?.outlet.component as Partial<ViewDidEnter>).ionViewDidEnter?.();
+        }
+
+        // After the view has entered for the first time, we can assume that it'll always be in the navigation stack
+        // until it's destroyed.
+        this.existsInNavigationStack = true;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    ionViewDidLeave(): void {
+        super.ionViewDidLeave();
+
+        // The `ionViewDidLeave` method is not called on nested outlets unless the active view changes, that's why
+        // we need to call it manually if the page is leaving and the last active component was not notified.
+        this.lastActiveComponent?.ionViewDidLeave?.();
+    }
+
     /**
      * Load the tab.
      *
@@ -165,6 +198,8 @@ export class CoreTabsOutletComponent extends CoreTabsBaseComponent<CoreTabsOutle
     ngOnDestroy(): void {
         super.ngOnDestroy();
         this.stackEventsSubscription?.unsubscribe();
+        this.outletActivatedSubscription?.unsubscribe();
+        this.existsInNavigationStack = false;
     }
 
 }