MOBILE-3833 settings: Warn user to restart app on language change

scripts/langindex.json

@@ -2167,6 +2167,8 @@
   "core.settings.cannotsyncloggedout": "local_moodlemobileapp",
   "core.settings.cannotsyncoffline": "local_moodlemobileapp",
   "core.settings.cannotsyncwithoutwifi": "local_moodlemobileapp",
+  "core.settings.changelanguage": "local_moodlemobileapp",
+  "core.settings.changelanguagealert": "local_moodlemobileapp",
   "core.settings.colorscheme": "local_moodlemobileapp",
   "core.settings.colorscheme-dark": "local_moodlemobileapp",
   "core.settings.colorscheme-light": "local_moodlemobileapp",

src/core/features/settings/lang.json

@@ -6,11 +6,13 @@
     "cannotsyncloggedout": "This site cannot be synchronised because you've logged out. Please try again when you're logged in the site again.",
     "cannotsyncoffline": "Cannot synchronise offline.",
     "cannotsyncwithoutwifi": "Cannot synchronise because the current settings only allow to synchronise when connected to Wi-Fi. Please connect to a Wi-Fi network.",
-    "colorscheme": "Color Scheme",
+    "changelanguage": "Change to {{$a}}",
+    "changelanguagealert": "Changing the language will restart the app.",
     "colorscheme-dark": "Dark",
     "colorscheme-light": "Light",
-    "colorscheme-system": "System default",
     "colorscheme-system-notice": "System default mode will depend on your device support.",
+    "colorscheme-system": "System default",
+    "colorscheme": "Color Scheme",
     "compilationinfo": "Compilation info",
     "copyinfo": "Copy device info on the clipboard",
     "cordovadevicemodel": "Cordova device model",

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

@@ -22,9 +22,10 @@ import { CorePushNotifications } from '@features/pushnotifications/services/push
 import { CoreSettingsHelper, CoreColorScheme, CoreZoomLevel } from '../../services/settings-helper';
 import { CoreApp } from '@services/app';
 import { CoreIframeUtils } from '@services/utils/iframe';
-import { Diagnostic } from '@singletons';
+import { Diagnostic, Translate } from '@singletons';
 import { CoreSites } from '@services/sites';
 import { CoreUtils } from '@services/utils/utils';
+import { AlertButton } from '@ionic/angular';
 
 /**
  * Page that displays the general settings.
@@ -110,14 +111,64 @@ export class CoreSettingsGeneralPage {
     /**
      * Called when a new language is selected.
      */
-    languageChanged(): void {
-        CoreLang.changeCurrentLanguage(this.selectedLanguage).finally(async () => {
-            // Invalidate cache for all sites to get the content in the right language.
-            const sites = await CoreSites.getSitesInstances();
-            await CoreUtils.ignoreErrors(Promise.all(sites.map((site) => site.invalidateWsCache())));
+    async languageChanged(): Promise<void> {
+        const previousLanguage = await CoreLang.getCurrentLanguage();
+        if (this.selectedLanguage === previousLanguage) {
+            // Prevent opening again.
 
-            CoreEvents.trigger(CoreEvents.LANGUAGE_CHANGED, this.selectedLanguage);
-        });
+            return;
+        }
+
+        const previousLanguageCancel = Translate.instant('core.cancel');
+
+        try {
+            await CoreLang.changeCurrentLanguage(this.selectedLanguage);
+        } finally {
+            const langName = this.languages.find((lang) => lang.code == this.selectedLanguage)?.name;
+
+            const buttons: AlertButton[] = [
+                {
+                    text: previousLanguageCancel,
+                    role: 'cancel',
+                    handler: (): void => {
+                        clearTimeout(timeout);
+                        this.selectedLanguage = previousLanguage;
+                        CoreLang.changeCurrentLanguage(this.selectedLanguage);
+                    },
+                },
+                {
+                    text: Translate.instant('core.settings.changelanguage', { $a: langName }),
+                    cssClass: 'timed-button',
+                    handler: (): void => {
+                        clearTimeout(timeout);
+                        this.applyLanguageAndRestart();
+                    },
+                },
+            ];
+
+            const alert = await CoreDomUtils.showAlertWithOptions(
+                {
+                    message: Translate.instant('core.settings.changelanguagealert'),
+                    buttons,
+                },
+            );
+            const timeout = window.setTimeout(async () => {
+                await alert.dismiss();
+                this.applyLanguageAndRestart();
+            }, 10000);
+        }
+    }
+
+    /**
+     * Apply language changes and restart the app.
+     */
+    protected async applyLanguageAndRestart(): Promise<void> {
+        // Invalidate cache for all sites to get the content in the right language.
+        const sites = await CoreSites.getSitesInstances();
+        await CoreUtils.ignoreErrors(Promise.all(sites.map((site) => site.invalidateWsCache())));
+
+        CoreEvents.trigger(CoreEvents.LANGUAGE_CHANGED, this.selectedLanguage);
+        window.location.reload();
     }
 
     /**

src/theme/theme.base.scss

@@ -461,6 +461,34 @@ ion-alert.core-nohead {
     }
 }
 
+@keyframes scaleFrom0 {
+    from {
+        /* More performant than animating `width` */
+        transform: scaleX(0);
+    }
+}
+
+ion-alert .alert-button.timed-button{
+    position: relative;
+
+    &::before {
+        content: '';
+        position: absolute;
+        width: 100%;
+        left: 0;
+        right: 0;
+        bottom: 0;
+        top: 0;
+        background-color: var(--primary-tint);
+        animation: scaleFrom0 10s forwards linear;
+        transform-origin: left;
+        @include rtl() {
+            transform-origin: right;
+        }
+        z-index: -1;
+    }
+}
+
 ion-alert {
     --border-radius: var(--huge-radius);