Merge pull request #2700 from dpalou/MOBILE-3712

Mobile 3712

src/app/app.component.test.ts

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-import { Observable } from 'rxjs';
+import { Observable, Subject } from 'rxjs';
 
 import { AppComponent } from '@/app/app.component';
 import { CoreApp } from '@services/app';
@@ -31,7 +31,7 @@ describe('AppComponent', () => {
     beforeEach(() => {
         mockSingleton(CoreApp, { setStatusBarColor: jest.fn() });
         mockSingleton(Network, { onChange: () => new Observable() });
-        mockSingleton(Platform, { ready: () => Promise.resolve() });
+        mockSingleton(Platform, { ready: () => Promise.resolve(), resume: new Subject<void>() });
         mockSingleton(NgZone, { run: jest.fn() });
 
         navigator = mockSingleton(CoreNavigator, ['navigate']);

src/app/app.component.ts

@@ -29,6 +29,10 @@ import { CoreApp } from '@services/app';
 import { CoreSites } from '@services/sites';
 import { CoreNavigator } from '@services/navigator';
 import { CoreSubscriptions } from '@singletons/subscriptions';
+import { CoreWindow } from '@singletons/window';
+import { CoreCustomURLSchemes } from '@services/urlschemes';
+import { CoreUtils } from '@services/utils/utils';
+import { CoreUrlUtils } from '@services/utils/url';
 
 @Component({
     selector: 'app-root',
@@ -39,6 +43,9 @@ export class AppComponent implements OnInit, AfterViewInit {
 
     @ViewChild(IonRouterOutlet) outlet?: IonRouterOutlet;
 
+    protected lastUrls: Record<string, number> = {};
+    protected lastInAppUrl?: string;
+
     /**
      * Component being initialized.
      *
@@ -51,6 +58,9 @@ export class AppComponent implements OnInit, AfterViewInit {
      * - Note: HideKeyboardFormAccessoryBar has been moved to config.xml.
      */
     ngOnInit(): void {
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        const win = <any> window;
+
         CoreEvents.on(CoreEvents.LOGOUT, () => {
             // Go to sites page when user is logged out.
             CoreNavigator.navigate('/login/sites', { reset: true });
@@ -80,6 +90,83 @@ export class AppComponent implements OnInit, AfterViewInit {
             CoreLoginHelper.sitePolicyNotAgreed(data.siteId);
         });
 
+        // Check URLs loaded in any InAppBrowser.
+        CoreEvents.on(CoreEvents.IAB_LOAD_START, (event) => {
+            // URLs with a custom scheme can be prefixed with "http://" or "https://", we need to remove this.
+            const url = event.url.replace(/^https?:\/\//, '');
+
+            if (CoreCustomURLSchemes.isCustomURL(url)) {
+                // Close the browser if it's a valid SSO URL.
+                CoreCustomURLSchemes.handleCustomURL(url).catch((error) => {
+                    CoreCustomURLSchemes.treatHandleCustomURLError(error);
+                });
+                CoreUtils.closeInAppBrowser();
+
+            } else if (CoreApp.instance.isAndroid()) {
+                // Check if the URL has a custom URL scheme. In Android they need to be opened manually.
+                const urlScheme = CoreUrlUtils.getUrlProtocol(url);
+                if (urlScheme && urlScheme !== 'file' && urlScheme !== 'cdvfile') {
+                    // Open in browser should launch the right app if found and do nothing if not found.
+                    CoreUtils.openInBrowser(url);
+
+                    // At this point the InAppBrowser is showing a "Webpage not available" error message.
+                    // Try to navigate to last loaded URL so this error message isn't found.
+                    if (this.lastInAppUrl) {
+                        CoreUtils.openInApp(this.lastInAppUrl);
+                    } else {
+                        // No last URL loaded, close the InAppBrowser.
+                        CoreUtils.closeInAppBrowser();
+                    }
+                } else {
+                    this.lastInAppUrl = url;
+                }
+            }
+        });
+
+        // Check InAppBrowser closed.
+        CoreEvents.on(CoreEvents.IAB_EXIT, () => {
+            CoreLoginHelper.setWaitingForBrowser(false);
+            this.lastInAppUrl = '';
+            CoreLoginHelper.checkLogout();
+        });
+
+        Platform.resume.subscribe(() => {
+            // Wait a second before setting it to false since in iOS there could be some frozen WS calls.
+            setTimeout(() => {
+                CoreLoginHelper.setWaitingForBrowser(false);
+                CoreLoginHelper.checkLogout();
+            }, 1000);
+        });
+
+        // Handle app launched with a certain URL (custom URL scheme).
+        win.handleOpenURL = (url: string): void => {
+            // Execute the callback in the Angular zone, so change detection doesn't stop working.
+            NgZone.run(() => {
+                // First check that the URL hasn't been treated a few seconds ago. Sometimes this function is called more than once.
+                if (this.lastUrls[url] && Date.now() - this.lastUrls[url] < 3000) {
+                    // Function called more than once, stop.
+                    return;
+                }
+
+                if (!CoreCustomURLSchemes.isCustomURL(url)) {
+                    // Not a custom URL, ignore.
+                    return;
+                }
+
+                this.lastUrls[url] = Date.now();
+
+                CoreEvents.trigger(CoreEvents.APP_LAUNCHED_URL, url);
+                CoreCustomURLSchemes.handleCustomURL(url).catch((error) => {
+                    CoreCustomURLSchemes.treatHandleCustomURLError(error);
+                });
+            });
+        };
+
+        // "Expose" CoreWindow.open.
+        win.openWindowSafely = (url: string, name?: string): void => {
+            CoreWindow.open(url, name);
+        };
+
         CoreEvents.on(CoreEvents.LOGIN, async (data: CoreEventSiteData) => {
             if (data.siteId) {
                 const site = await CoreSites.getSite(data.siteId);

src/core/core.module.ts

@@ -47,12 +47,13 @@ import { CoreFileHelperProvider } from '@services/file-helper';
 import { CoreGeolocationProvider } from '@services/geolocation';
 import { CoreNavigatorService } from '@services/navigator';
 import { CoreScreenService } from '@services/screen';
+import { CoreCustomURLSchemesProvider } from '@services/urlschemes';
 
 export const CORE_SERVICES: Type<unknown>[] = [
     CoreAppProvider,
     CoreConfigProvider,
     CoreCronDelegateService,
-    // @todo CoreCustomURLSchemesProvider,
+    CoreCustomURLSchemesProvider,
     CoreDbProvider,
     CoreFileHelperProvider,
     CoreFileSessionProvider,

src/core/directives/link.ts

@@ -23,6 +23,7 @@ import { CoreUtils } from '@services/utils/utils';
 import { CoreTextUtils } from '@services/utils/text';
 import { CoreConstants } from '@/core/constants';
 import { CoreContentLinksHelper } from '@features/contentlinks/services/contentlinks-helper';
+import { CoreCustomURLSchemes } from '@services/urlschemes';
 
 /**
  * Directive to open a link in external browser or in the app.
@@ -111,7 +112,15 @@ export class CoreLinkDirective implements OnInit {
             return;
         }
 
-        // @todo: Custom URL schemes.
+        if (CoreCustomURLSchemes.isCustomURL(href)) {
+            try {
+                await CoreCustomURLSchemes.handleCustomURL(href);
+            } catch (error) {
+                CoreCustomURLSchemes.treatHandleCustomURLError(error);
+            }
+
+            return;
+        }
 
         return this.openExternalLink(href, openIn);
     }

src/core/features/editor/components/rich-text-editor/rich-text-editor.ts

@@ -1018,9 +1018,9 @@ export class CoreEditorRichTextEditorComponent implements OnInit, AfterContentIn
         const text = await CoreUtils.scanQR();
 
         if (text) {
+            this.editorElement?.focus(); // Make sure the editor is focused.
             document.execCommand('insertText', false, text);
         }
-        // this.content.resize(); // Resize content, otherwise the content height becomes 1 for some reason.
     }
 
     /**

src/core/features/login/pages/credentials/credentials.ts

@@ -18,8 +18,7 @@ import { FormBuilder, FormGroup, Validators } from '@angular/forms';
 import { CoreApp } from '@services/app';
 import { CoreSites } from '@services/sites';
 import { CoreDomUtils } from '@services/utils/dom';
-import { CoreUtils } from '@services/utils/utils';
-import { CoreLoginHelper, CoreLoginHelperProvider } from '@features/login/services/login-helper';
+import { CoreLoginHelper } from '@features/login/services/login-helper';
 import { CoreConstants } from '@/core/constants';
 import { Translate } from '@singletons';
 import { CoreSiteIdentityProvider, CoreSitePublicConfigResponse } from '@classes/site';
@@ -50,7 +49,7 @@ export class CoreLoginCredentialsPage implements OnInit, OnDestroy {
     isBrowserSSO = false;
     isFixedUrlSet = false;
     showForgottenPassword = true;
-    showScanQR: boolean;
+    showScanQR = false;
 
     protected siteConfig?: CoreSitePublicConfigResponse;
     protected eventThrown = false;
@@ -60,19 +59,7 @@ export class CoreLoginCredentialsPage implements OnInit, OnDestroy {
 
     constructor(
         protected fb: FormBuilder,
-    ) {
-
-        const canScanQR = CoreUtils.canScanQR();
-        if (canScanQR) {
-            if (typeof CoreConstants.CONFIG.displayqroncredentialscreen == 'undefined') {
-                this.showScanQR = CoreLoginHelper.isFixedUrlSet();
-            } else {
-                this.showScanQR = !!CoreConstants.CONFIG.displayqroncredentialscreen;
-            }
-        } else {
-            this.showScanQR = false;
-        }
-    }
+    ) {}
 
     /**
      * Initialize the component.
@@ -91,6 +78,7 @@ export class CoreLoginCredentialsPage implements OnInit, OnDestroy {
         this.logoUrl = !CoreConstants.CONFIG.forceLoginLogo && CoreNavigator.getRouteParam('logoUrl') || undefined;
         this.siteConfig = CoreNavigator.getRouteParam('siteConfig');
         this.urlToOpen = CoreNavigator.getRouteParam('urlToOpen');
+        this.showScanQR = CoreLoginHelper.displayQRInCredentialsScreen();
 
         this.credForm = this.fb.group({
             username: [CoreNavigator.getRouteParam<string>('username') || '', Validators.required],
@@ -285,37 +273,17 @@ export class CoreLoginCredentialsPage implements OnInit, OnDestroy {
 
     /**
      * Show instructions and scan QR code.
-     */
-    showInstructionsAndScanQR(): void {
-        // Show some instructions first.
-        CoreDomUtils.showAlertWithOptions({
-            header: Translate.instant('core.login.faqwhereisqrcode'),
-            message: Translate.instant(
-                'core.login.faqwhereisqrcodeanswer',
-                { $image: CoreLoginHelperProvider.FAQ_QRCODE_IMAGE_HTML },
-            ),
-            buttons: [
-                {
-                    text: Translate.instant('core.cancel'),
-                    role: 'cancel',
-                },
-                {
-                    text: Translate.instant('core.next'),
-                    handler: (): void => {
-                        this.scanQR();
-                    },
-                },
-            ],
-        });
-    }
-
-    /**
-     * Scan a QR code and put its text in the URL input.
      *
      * @return Promise resolved when done.
      */
-    async scanQR(): Promise<void> {
-        // @todo Scan for a QR code.
+    async showInstructionsAndScanQR(): Promise<void> {
+        try {
+            await CoreLoginHelper.showScanQRInstructions();
+
+            await CoreLoginHelper.scanQR();
+        } catch {
+            // Ignore errors.
+        }
     }
 
     /**

src/core/features/login/pages/reconnect/reconnect.html

@@ -61,6 +61,14 @@
                 </ion-col>
             </ion-row>
         </ion-grid>
+
+        <ng-container *ngIf="showScanQR">
+            <div class="ion-text-center ion-padding">{{ 'core.login.or' | translate }}</div>
+            <ion-button expand="block" color="light" class="ion-margin" lines="none" (click)="showInstructionsAndScanQR()">
+                <ion-icon slot="start" name="fas-qrcode" aria-hidden="true"></ion-icon>
+                <ion-label>{{ 'core.scanqr' | translate }}</ion-label>
+            </ion-button>
+        </ng-container>
     </form>
 
     <!-- Forgotten password option. -->

src/core/features/login/pages/reconnect/reconnect.ts

@@ -51,6 +51,7 @@ export class CoreLoginReconnectPage implements OnInit, OnDestroy {
     isOAuth = false;
     isLoggedOut: boolean;
     siteId!: string;
+    showScanQR = false;
 
     protected page?: string;
     protected pageParams?: Params;
@@ -82,6 +83,7 @@ export class CoreLoginReconnectPage implements OnInit, OnDestroy {
         this.siteUrl = siteId;
         this.page = CoreNavigator.getRouteParam('pageName');
         this.pageParams = CoreNavigator.getRouteParam('pageParams');
+        this.showScanQR = CoreLoginHelper.displayQRInSiteScreen() || CoreLoginHelper.displayQRInCredentialsScreen();
 
         try {
             const site = await CoreSites.getSite(this.siteId);
@@ -246,4 +248,19 @@ export class CoreLoginReconnectPage implements OnInit, OnDestroy {
         }
     }
 
+    /**
+     * Show instructions and scan QR code.
+     *
+     * @return Promise resolved when done.
+     */
+    async showInstructionsAndScanQR(): Promise<void> {
+        try {
+            await CoreLoginHelper.showScanQRInstructions();
+
+            await CoreLoginHelper.scanQR();
+        } catch {
+            // Ignore errors.
+        }
+    }
+
 }

src/core/features/login/pages/site/site.ts

@@ -30,6 +30,8 @@ import { CoreUrlUtils } from '@services/utils/url';
 import { CoreLoginSiteHelpComponent } from '@features/login/components/site-help/site-help';
 import { CoreLoginSiteOnboardingComponent } from '@features/login/components/site-onboarding/site-onboarding';
 import { CoreNavigator } from '@services/navigator';
+import { CoreCustomURLSchemes, CoreCustomURLSchemesHandleError } from '@services/urlschemes';
+import { CoreTextUtils } from '@services/utils/text';
 
 /**
  * Page that displays a "splash screen" while the app is being initialized.
@@ -82,8 +84,7 @@ export class CoreLoginSitePage implements OnInit {
             this.initOnboarding();
         }
 
-        this.showScanQR = CoreUtils.canScanQR() && (typeof CoreConstants.CONFIG.displayqronsitescreen == 'undefined' ||
-            !!CoreConstants.CONFIG.displayqronsitescreen);
+        this.showScanQR = CoreLoginHelper.displayQRInSiteScreen();
 
         this.siteForm = this.formBuilder.group({
             siteUrl: [url, this.moodleUrlValidator()],
@@ -464,28 +465,17 @@ export class CoreLoginSitePage implements OnInit {
 
     /**
      * Show instructions and scan QR code.
+     *
+     * @return Promise resolved when done.
      */
-    showInstructionsAndScanQR(): void {
-        // Show some instructions first.
-        CoreDomUtils.showAlertWithOptions({
-            header: Translate.instant('core.login.faqwhereisqrcode'),
-            message: Translate.instant(
-                'core.login.faqwhereisqrcodeanswer',
-                { $image: CoreLoginHelperProvider.FAQ_QRCODE_IMAGE_HTML },
-            ),
-            buttons: [
-                {
-                    text: Translate.instant('core.cancel'),
-                    role: 'cancel',
-                },
-                {
-                    text: Translate.instant('core.next'),
-                    handler: (): void => {
-                        this.scanQR();
-                    },
-                },
-            ],
-        });
+    async showInstructionsAndScanQR(): Promise<void> {
+        try {
+            await CoreLoginHelper.showScanQRInstructions();
+
+            await this.scanQR();
+        } catch {
+            // Ignore errors.
+        }
     }
 
     /**
@@ -497,9 +487,83 @@ export class CoreLoginSitePage implements OnInit {
         // Scan for a QR code.
         const text = await CoreUtils.scanQR();
 
-        if (text) {
-            // @todo
+        if (!text) {
+            return;
         }
+
+        if (CoreCustomURLSchemes.isCustomURL(text)) {
+            try {
+                await CoreCustomURLSchemes.handleCustomURL(text);
+            } catch (error) {
+                if (error && error.data && error.data.isAuthenticationURL && error.data.siteUrl) {
+                    // An error ocurred, but it's an authentication URL and we have the site URL.
+                    this.treatErrorInAuthenticationCustomURL(text, error);
+                } else {
+                    CoreCustomURLSchemes.treatHandleCustomURLError(error);
+                }
+            }
+
+            return;
+        }
+
+        // Not a custom URL scheme, check if it's a URL scheme to another app.
+        const scheme = CoreUrlUtils.getUrlProtocol(text);
+
+        if (scheme && scheme != 'http' && scheme != 'https') {
+            CoreDomUtils.showErrorModal(Translate.instant('core.errorurlschemeinvalidscheme', { $a: text }));
+        } else if (CoreLoginHelper.isSiteUrlAllowed(text)) {
+            // Put the text in the field (if present).
+            this.siteForm.controls.siteUrl.setValue(text);
+
+            this.connect(new Event('click'), text);
+        } else {
+            CoreDomUtils.showErrorModal('core.errorurlschemeinvalidsite', true);
+        }
+    }
+
+    /**
+     * Treat an error while handling a custom URL meant to perform an authentication.
+     * If the site doesn't use SSO, the user will be sent to the credentials screen.
+     *
+     * @param customURL Custom URL handled.
+     * @param error Error data.
+     * @return Promise resolved when done.
+     */
+    protected async treatErrorInAuthenticationCustomURL(customURL: string, error: CoreCustomURLSchemesHandleError): Promise<void> {
+        const siteUrl = error.data?.siteUrl || '';
+        const modal = await CoreDomUtils.showModalLoading();
+
+        // Set the site URL in the input.
+        this.siteForm.controls.siteUrl.setValue(siteUrl);
+
+        try {
+            // Check if site uses SSO.
+            const response = await CoreSites.checkSite(siteUrl);
+
+            await CoreSites.checkApplication(response);
+
+            if (!CoreLoginHelper.isSSOLoginNeeded(response.code)) {
+                // No SSO, go to credentials page.
+                await CoreNavigator.navigate('/login/credentials', {
+                    params: {
+                        siteUrl: response.siteUrl,
+                        siteConfig: response.config,
+                    },
+                });
+            }
+        } catch (error) {
+            // Ignore errors.
+        } finally {
+            modal.dismiss();
+        }
+
+        // Now display the error.
+        error.error = CoreTextUtils.addTextToError(
+            error.error,
+            '<br><br>' + Translate.instant('core.login.youcanstillconnectwithcredentials'),
+        );
+
+        CoreCustomURLSchemes.treatHandleCustomURLError(error);
     }
 
 }

src/core/features/login/services/login-helper.ts

@@ -33,6 +33,8 @@ import { makeSingleton, Translate } from '@singletons';
 import { CoreLogger } from '@singletons/logger';
 import { CoreUrl } from '@singletons/url';
 import { CoreNavigator } from '@services/navigator';
+import { CoreCanceledError } from '@classes/errors/cancelederror';
+import { CoreCustomURLSchemes } from '@services/urlschemes';
 
 /**
  * Helper provider that provides some common features regarding authentication.
@@ -53,7 +55,7 @@ export class CoreLoginHelperProvider {
     protected isSSOConfirmShown = false;
     protected isOpenEditAlertShown = false;
     protected isOpeningReconnect = false;
-    waitingForBrowser = false;
+    protected waitingForBrowser = false;
 
     constructor() {
         this.logger = CoreLogger.getInstance('CoreLoginHelper');
@@ -319,7 +321,7 @@ export class CoreLoginHelperProvider {
      * @param params Params.
      * @return OAuth ID.
      */
-    getOAuthIdFromParams(params: CoreUrlParams): number | undefined {
+    getOAuthIdFromParams(params?: CoreUrlParams): number | undefined {
         return params && typeof params.oauthsso != 'undefined' ? Number(params.oauthsso) : undefined;
     }
 
@@ -1221,6 +1223,110 @@ export class CoreLoginHelperProvider {
         }
     }
 
+    /**
+     * Return whether the app is waiting for browser.
+     *
+     * @return Whether the app is waiting for browser.
+     */
+    isWaitingForBrowser(): boolean {
+        return this.waitingForBrowser;
+    }
+
+    /**
+     * Set whether the app is waiting for browser.
+     *
+     * @param value New value.
+     */
+    setWaitingForBrowser(value: boolean): void {
+        this.waitingForBrowser = value;
+    }
+
+    /**
+     * Check whether the QR reader should be displayed in site screen.
+     *
+     * @return Whether the QR reader should be displayed in site screen.
+     */
+    displayQRInSiteScreen(): boolean {
+        return CoreUtils.canScanQR() && (typeof CoreConstants.CONFIG.displayqronsitescreen == 'undefined' ||
+            !!CoreConstants.CONFIG.displayqronsitescreen);
+    }
+
+    /**
+     * Check whether the QR reader should be displayed in credentials screen.
+     *
+     * @return Whether the QR reader should be displayed in credentials screen.
+     */
+    displayQRInCredentialsScreen(): boolean {
+        if (!CoreUtils.canScanQR()) {
+            return false;
+        }
+
+        return (CoreConstants.CONFIG.displayqroncredentialscreen === undefined && this.isFixedUrlSet()) ||
+            (CoreConstants.CONFIG.displayqroncredentialscreen !== undefined && !!CoreConstants.CONFIG.displayqroncredentialscreen);
+    }
+
+    /**
+     * Show instructions to scan QR code.
+     *
+     * @return Promise resolved if the user accepts to scan QR.
+     */
+    showScanQRInstructions(): Promise<void> {
+        const deferred = CoreUtils.promiseDefer<void>();
+
+        // Show some instructions first.
+        CoreDomUtils.showAlertWithOptions({
+            header: Translate.instant('core.login.faqwhereisqrcode'),
+            message: Translate.instant(
+                'core.login.faqwhereisqrcodeanswer',
+                { $image: CoreLoginHelperProvider.FAQ_QRCODE_IMAGE_HTML },
+            ),
+            buttons: [
+                {
+                    text: Translate.instant('core.cancel'),
+                    role: 'cancel',
+                    handler: (): void => {
+                        deferred.reject(new CoreCanceledError());
+                    },
+                },
+                {
+                    text: Translate.instant('core.next'),
+                    handler: (): void => {
+                        deferred.resolve();
+                    },
+                },
+            ],
+        });
+
+        return deferred.promise;
+    }
+
+    /**
+     * Scan a QR code and tries to authenticate the user using custom URL scheme.
+     *
+     * @return Promise resolved when done.
+     */
+    async scanQR(): Promise<void> {
+        // Scan for a QR code.
+        const text = await CoreUtils.scanQR();
+
+        if (text && CoreCustomURLSchemes.isCustomURL(text)) {
+            try {
+                await CoreCustomURLSchemes.handleCustomURL(text);
+            } catch (error) {
+                CoreCustomURLSchemes.treatHandleCustomURLError(error);
+            }
+        } else if (text) {
+            // Not a custom URL scheme, check if it's a URL scheme to another app.
+            const scheme = CoreUrlUtils.getUrlProtocol(text);
+
+            if (scheme && scheme != 'http' && scheme != 'https') {
+                CoreDomUtils.showErrorModal(Translate.instant('core.errorurlschemeinvalidscheme', { $a: text }));
+            } else {
+                CoreDomUtils.showErrorModal('core.login.errorqrnoscheme', true);
+            }
+        }
+    }
+
 }
 
 export const CoreLoginHelper = makeSingleton(CoreLoginHelperProvider);

src/core/features/mainmenu/pages/more/more.ts

@@ -23,6 +23,10 @@ import { CoreMainMenuDelegate, CoreMainMenuHandlerData } from '../../services/ma
 import { CoreMainMenu, CoreMainMenuCustomItem } from '../../services/mainmenu';
 import { CoreEventObserver, CoreEvents } from '@singletons/events';
 import { CoreNavigator } from '@services/navigator';
+import { CoreCustomURLSchemes } from '@services/urlschemes';
+import { CoreContentLinksHelper } from '@features/contentlinks/services/contentlinks-helper';
+import { CoreTextUtils } from '@services/utils/text';
+import { Translate } from '@singletons';
 
 /**
  * Page that displays the main menu of the app.
@@ -154,10 +158,31 @@ export class CoreMainMenuMorePage implements OnInit, OnDestroy {
      */
     async scanQR(): Promise<void> {
         // Scan for a QR code.
-        // @todo
-        // eslint-disable-next-line no-console
-        console.error('scanQR not implemented');
+        const text = await CoreUtils.scanQR();
 
+        if (!text) {
+            return;
+        }
+
+        if (CoreCustomURLSchemes.isCustomURL(text)) {
+            // Is a custom URL scheme, handle it.
+            CoreCustomURLSchemes.handleCustomURL(text).catch((error) => {
+                CoreCustomURLSchemes.treatHandleCustomURLError(error);
+            });
+        } else if (/^[^:]{2,}:\/\/[^ ]+$/i.test(text)) { // Check if it's a URL.
+            // Check if the app can handle the URL.
+            const treated = await CoreContentLinksHelper.handleLink(text, undefined, true, true);
+
+            if (!treated) {
+                // Can't handle it, open it in browser.
+                CoreSites.getCurrentSite()?.openInBrowserWithAutoLoginIfSameSite(text);
+            }
+        } else {
+            // It's not a URL, open it in a modal so the user can see it and copy it.
+            CoreTextUtils.viewText(Translate.instant('core.qrscanner'), text, {
+                displayCopyButton: true,
+            });
+        }
     }
 
     /**

src/core/features/viewer/components/components.module.ts

@@ -16,11 +16,13 @@ import { NgModule } from '@angular/core';
 
 import { CoreSharedModule } from '@/core/shared.module';
 import { CoreViewerImageComponent } from './image/image';
+import { CoreViewerQRScannerComponent } from './qr-scanner/qr-scanner';
 import { CoreViewerTextComponent } from './text/text';
 
 @NgModule({
     declarations: [
         CoreViewerImageComponent,
+        CoreViewerQRScannerComponent,
         CoreViewerTextComponent,
     ],
     imports: [
@@ -28,6 +30,7 @@ import { CoreViewerTextComponent } from './text/text';
     ],
     exports: [
         CoreViewerImageComponent,
+        CoreViewerQRScannerComponent,
         CoreViewerTextComponent,
     ],
 })

src/core/features/viewer/components/qr-scanner/qr-scanner.html

@@ -0,0 +1,12 @@
+<ion-header>
+    <ion-toolbar>
+        <ion-title>{{ title }}</ion-title>
+        <ion-buttons slot="end">
+            <ion-button (click)="closeModal()" [attr.aria-label]="'core.close' | translate">
+                <ion-icon name="fas-times" slot="icon-only"></ion-icon>
+            </ion-button>
+        </ion-buttons>
+    </ion-toolbar>
+</ion-header>
+<ion-content>
+</ion-content>

src/core/features/viewer/components/qr-scanner/qr-scanner.ts

@@ -0,0 +1,80 @@
+// (C) Copyright 2015 Moodle Pty Ltd.
+//
+// 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, OnDestroy, OnInit } from '@angular/core';
+import { CoreDomUtils } from '@services/utils/dom';
+import { CoreUtils } from '@services/utils/utils';
+import { ModalController, Translate } from '@singletons';
+
+/**
+ * Page to scan a QR code.
+ */
+@Component({
+    selector: 'core-viewer-qr-scanner',
+    templateUrl: 'qr-scanner.html',
+})
+export class CoreViewerQRScannerComponent implements OnInit, OnDestroy {
+
+    @Input() title?: string; // Page title.
+
+    /**
+     * @inheritdoc
+     */
+    async ngOnInit(): Promise<void> {
+        this.title = this.title || Translate.instant('core.scanqr');
+
+        try {
+
+            let text = await CoreUtils.startScanQR();
+
+            // Text captured, return it.
+            text = typeof text == 'string' ? text.trim() : '';
+
+            this.closeModal(text);
+        } catch (error) {
+            if (!CoreDomUtils.isCanceledError(error)) {
+                // Show error and stop scanning.
+                CoreDomUtils.showErrorModalDefault(error, 'An error occurred.');
+                CoreUtils.stopScanQR();
+            }
+
+            this.closeModal();
+        }
+    }
+
+    /**
+     * Cancel scanning.
+     */
+    cancel(): void {
+        CoreUtils.stopScanQR();
+    }
+
+    /**
+     * Close modal.
+     *
+     * @param text The text to return (if any).
+     */
+    closeModal(text?: string): void {
+        ModalController.dismiss(text);
+    }
+
+    /**
+     * @inheritdoc
+     */
+    ngOnDestroy(): void {
+        // If this code is reached and scan hasn't been stopped yet it means the user clicked the back button, cancel.
+        CoreUtils.stopScanQR();
+    }
+
+}

src/core/services/sites.ts

@@ -498,6 +498,9 @@ export class CoreSitesProvider {
                 this.currentSite = candidateSite;
                 // Store session.
                 this.login(siteId);
+            } else if (this.currentSite && this.currentSite.getId() == siteId) {
+                // Current site has just been updated, trigger the event.
+                CoreEvents.trigger(CoreEvents.SITE_UPDATED, info, siteId);
             }
 
             CoreEvents.trigger(CoreEvents.SITE_ADDED, info, siteId);

src/core/services/urlschemes.ts

@@ -0,0 +1,564 @@
+// (C) Copyright 2015 Moodle Pty Ltd.
+//
+// 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 { Injectable } from '@angular/core';
+
+import { CoreError } from '@classes/errors/error';
+import { CoreWSError } from '@classes/errors/wserror';
+import { CoreContentLinksDelegate } from '@features/contentlinks/services/contentlinks-delegate';
+import { CoreContentLinksHelper } from '@features/contentlinks/services/contentlinks-helper';
+import { CoreLoginHelper, CoreLoginSSOData } from '@features/login/services/login-helper';
+import { CoreSitePlugins } from '@features/siteplugins/services/siteplugins';
+import { ApplicationInit, makeSingleton, Translate } from '@singletons';
+import { CoreLogger } from '@singletons/logger';
+import { CoreConstants } from '../constants';
+import { CoreApp } from './app';
+import { CoreNavigator } from './navigator';
+import { CoreSiteCheckResponse, CoreSites } from './sites';
+import { CoreDomUtils } from './utils/dom';
+import { CoreTextErrorObject, CoreTextUtils } from './utils/text';
+import { CoreUrlUtils } from './utils/url';
+import { CoreUtils } from './utils/utils';
+
+/*
+ * Provider to handle custom URL schemes.
+ */
+@Injectable({ providedIn: 'root' })
+export class CoreCustomURLSchemesProvider {
+
+    protected logger: CoreLogger;
+    protected lastUrls: Record<string, number> = {};
+
+    constructor() {
+        this.logger = CoreLogger.getInstance('CoreCustomURLSchemesProvider');
+    }
+
+    /**
+     * Given some data of a custom URL with a token, create a site if it needs to be created.
+     *
+     * @param data URL data.
+     * @return Promise resolved with the site ID if created or already exists.
+     */
+    protected async createSiteIfNeeded(data: CoreCustomURLSchemesParams): Promise<string | undefined> {
+        if (!data.token) {
+            return;
+        }
+
+        const currentSite = CoreSites.getCurrentSite();
+
+        if (!currentSite || currentSite.getToken() != data.token) {
+            // Token belongs to a different site, create it. It doesn't matter if it already exists.
+
+            if (!data.siteUrl.match(/^https?:\/\//)) {
+                // URL doesn't have a protocol and it's required to be able to create the site. Check which one to use.
+                const result = await CoreSites.checkSite(data.siteUrl);
+
+                data.siteUrl = result.siteUrl;
+
+                await CoreSites.checkApplication(result);
+            }
+
+            return CoreSites.newSite(
+                data.siteUrl,
+                data.token,
+                data.privateToken,
+                !!data.isSSOToken,
+                CoreLoginHelper.getOAuthIdFromParams(data.ssoUrlParams),
+            );
+        } else {
+            // Token belongs to current site, no need to create it.
+            return CoreSites.getCurrentSiteId();
+        }
+    }
+
+    /**
+     * Handle an URL received by custom URL scheme.
+     *
+     * @param url URL to treat.
+     * @return Promise resolved when done. If rejected, the parameter is of type CoreCustomURLSchemesHandleError.
+     */
+    async handleCustomURL(url: string): Promise<void> {
+        if (!this.isCustomURL(url)) {
+            throw new CoreCustomURLSchemesHandleError(null);
+        }
+
+        /* First check that this URL hasn't been treated a few seconds ago. The function that handles custom URL schemes already
+           does this, but this function is called from other places so we need to handle it in here too. */
+        if (this.lastUrls[url] && Date.now() - this.lastUrls[url] < 3000) {
+            // Function called more than once, stop.
+            return;
+        }
+
+        this.lastUrls[url] = Date.now();
+        url = CoreTextUtils.decodeURIComponent(url);
+
+        // Wait for app to be ready.
+        await ApplicationInit.donePromise;
+
+        // Some platforms like Windows add a slash at the end. Remove it.
+        // Some sites add a # at the end of the URL. If it's there, remove it.
+        url = url.replace(/\/?#?\/?$/, '');
+
+        const modal = await CoreDomUtils.showModalLoading();
+        let data: CoreCustomURLSchemesParams;
+
+        // Get the data from the URL.
+        try {
+            if (this.isCustomURLToken(url)) {
+                data = await this.getCustomURLTokenData(url);
+            } else if (this.isCustomURLLink(url)) {
+                // In iOS, the protocol after the scheme doesn't have ":". Add it.
+                url = url.replace(/\/\/link=(https?)\/\//, '//link=$1://');
+
+                data = await this.getCustomURLLinkData(url);
+            } else {
+                // In iOS, the protocol after the scheme doesn't have ":". Add it.
+                url = url.replace(/\/\/(https?)\/\//, '//$1://');
+
+                data = await this.getCustomURLData(url);
+            }
+        } catch (error) {
+            modal.dismiss();
+
+            throw error;
+        }
+
+        try {
+            const isValid = await CoreLoginHelper.isSiteUrlAllowed(data.siteUrl);
+
+            if (!isValid) {
+                throw Translate.instant('core.errorurlschemeinvalidsite');
+            }
+
+            if (data.redirect && data.redirect.match(/^https?:\/\//) && data.redirect.indexOf(data.siteUrl) == -1) {
+                // Redirect URL must belong to the same site. Reject.
+                throw Translate.instant('core.contentlinks.errorredirectothersite');
+            }
+
+            // First of all, create the site if needed.
+            const siteId = await this.createSiteIfNeeded(data);
+
+            if (data.isSSOToken || (data.isAuthenticationURL && siteId && CoreSites.getCurrentSiteId() == siteId)) {
+                // Site created and authenticated, open the page to go.
+                if (data.pageName) {
+                    // Page defined, go to that page instead of site initial page.
+                    CoreNavigator.navigateToSitePath(data.pageName, {
+                        params: data.pageParams,
+                    });
+                } else {
+                    CoreNavigator.navigateToSiteHome();
+                }
+
+                return;
+            }
+
+            if (data.redirect && !data.redirect.match(/^https?:\/\//)) {
+                // Redirect is a relative URL. Append the site URL.
+                data.redirect = CoreTextUtils.concatenatePaths(data.siteUrl, data.redirect);
+            }
+
+            let siteIds = [siteId];
+
+            if (!siteId) {
+                // No site created, check if the site is stored (to know which one to use).
+                siteIds = await CoreSites.getSiteIdsFromUrl(data.siteUrl, true, data.username);
+            }
+
+            if (siteIds.length > 1) {
+                // More than one site to treat the URL, let the user choose.
+                CoreContentLinksHelper.goToChooseSite(data.redirect || data.siteUrl);
+
+            } else if (siteIds.length == 1) {
+                // Only one site, handle the link.
+                const site = await CoreSites.getSite(siteIds[0]);
+
+                if (!data.redirect) {
+                    // No redirect, go to the root URL if needed.
+                    await CoreContentLinksHelper.handleRootURL(site, false, true);
+                } else {
+                    // Handle the redirect link.
+                    modal.dismiss(); // Dismiss modal so it doesn't collide with confirms.
+
+                    /* Always use the username from the site in this case. If the link has a username and a token,
+                       this will make sure that the link is opened with the user the token belongs to. */
+                    const username = site.getInfo()?.username || data.username;
+
+                    const treated = await CoreContentLinksHelper.handleLink(data.redirect, username);
+
+                    if (!treated) {
+                        CoreDomUtils.showErrorModal('core.contentlinks.errornoactions', true);
+                    }
+                }
+
+            } else {
+                // Site not stored. Try to add the site.
+                const result = await CoreSites.checkSite(data.siteUrl);
+
+                // Site exists. We'll allow to add it.
+                modal.dismiss(); // Dismiss modal so it doesn't collide with confirms.
+
+                await this.goToAddSite(data, result);
+            }
+
+        } catch (error) {
+            throw new CoreCustomURLSchemesHandleError(error, data);
+        } finally {
+            modal.dismiss();
+
+            if (data.isSSOToken) {
+                CoreApp.finishSSOAuthentication();
+            }
+        }
+    }
+
+    /**
+     * Get the data from a custom URL scheme. The structure of the URL is:
+     * moodlemobile://username@domain.com?token=TOKEN&privatetoken=PRIVATETOKEN&redirect=http://domain.com/course/view.php?id=2
+     *
+     * @param url URL to treat.
+     * @return Promise resolved with the data.
+     */
+    protected async getCustomURLData(url: string): Promise<CoreCustomURLSchemesParams> {
+        if (!this.isCustomURL(url)) {
+            throw new CoreCustomURLSchemesHandleError(null);
+        }
+
+        // App opened using custom URL scheme.
+        this.logger.debug('Treating custom URL scheme: ' + url);
+
+        // Delete the sso scheme from the URL.
+        url = this.removeCustomURLScheme(url);
+
+        // Detect if there's a user specified.
+        const username = CoreUrlUtils.getUsernameFromUrl(url);
+        if (username) {
+            url = url.replace(username + '@', ''); // Remove the username from the URL.
+        }
+
+        // Get the params of the URL.
+        const params = CoreUrlUtils.extractUrlParams(url);
+
+        // Remove the params to get the site URL.
+        if (url.indexOf('?') != -1) {
+            url = url.substr(0, url.indexOf('?'));
+        }
+
+        if (!url.match(/https?:\/\//)) {
+            // Url doesn't have a protocol. Check if the site is stored in the app to be able to determine the protocol.
+            const siteIds = await CoreSites.getSiteIdsFromUrl(url, true, username);
+
+            if (siteIds.length) {
+                // There is at least 1 site with this URL. Use it to know the full URL.
+                const site = await CoreSites.getSite(siteIds[0]);
+
+                url = site.getURL();
+            }
+        }
+
+        return {
+            siteUrl: url,
+            username: username,
+            token: params.token,
+            privateToken: params.privateToken,
+            redirect: params.redirect,
+            isAuthenticationURL: !!params.token,
+        };
+    }
+
+    /**
+     * Get the data from a "link" custom URL scheme. This kind of URL is deprecated.
+     *
+     * @param url URL to treat.
+     * @return Promise resolved with the data.
+     */
+    protected async getCustomURLLinkData(url: string): Promise<CoreCustomURLSchemesParams> {
+        if (!this.isCustomURLLink(url)) {
+            throw new CoreCustomURLSchemesHandleError(null);
+        }
+
+        // App opened using custom URL scheme.
+        this.logger.debug('Treating custom URL scheme with link param: ' + url);
+
+        // Delete the sso scheme from the URL.
+        url = this.removeCustomURLLinkScheme(url);
+
+        // Detect if there's a user specified.
+        const username = CoreUrlUtils.getUsernameFromUrl(url);
+        if (username) {
+            url = url.replace(username + '@', ''); // Remove the username from the URL.
+        }
+
+        // First of all, check if it's the root URL of a site.
+        const data = await CoreSites.isStoredRootURL(url, username);
+
+        if (data.site) {
+            // Root URL.
+            return {
+                siteUrl: data.site.getURL(),
+                username: username,
+            };
+
+        } else if (data.siteIds.length > 0) {
+            // Not the root URL, but at least 1 site supports the URL. Get the site URL from the list of sites.
+            const site = await CoreSites.getSite(data.siteIds[0]);
+
+            return {
+                siteUrl: site.getURL(),
+                username: username,
+                redirect: url,
+            };
+
+        } else {
+            // Get the site URL.
+            let siteUrl = CoreContentLinksDelegate.getSiteUrl(url);
+            let redirect: string | undefined = url;
+
+            if (!siteUrl) {
+                // Site URL not found, use the original URL since it could be the root URL of the site.
+                siteUrl = url;
+                redirect = undefined;
+            }
+
+            return {
+                siteUrl: siteUrl,
+                username: username,
+                redirect: redirect,
+            };
+        }
+    }
+
+    /**
+     * Get the data from a "token" custom URL scheme. This kind of URL is deprecated.
+     *
+     * @param url URL to treat.
+     * @return Promise resolved with the data.
+     */
+    protected async getCustomURLTokenData(url: string): Promise<CoreCustomURLSchemesParams> {
+        if (!this.isCustomURLToken(url)) {
+            throw new CoreCustomURLSchemesHandleError(null);
+        }
+
+        if (CoreApp.isSSOAuthenticationOngoing()) {
+            // Authentication ongoing, probably duplicated request.
+            throw new CoreCustomURLSchemesHandleError('Duplicated');
+        }
+
+        // App opened using custom URL scheme. Probably an SSO authentication.
+        CoreApp.startSSOAuthentication();
+        this.logger.debug('App launched by URL with an SSO');
+
+        // Delete the sso scheme from the URL.
+        url = this.removeCustomURLTokenScheme(url);
+
+        // Some platforms like Windows add a slash at the end. Remove it.
+        // Some sites add a # at the end of the URL. If it's there, remove it.
+        url = url.replace(/\/?#?\/?$/, '');
+
+        // Decode from base64.
+        try {
+            url = atob(url);
+        } catch (err) {
+            // Error decoding the parameter.
+            this.logger.error('Error decoding parameter received for login SSO');
+
+            throw new CoreCustomURLSchemesHandleError(null);
+        }
+
+        const data: CoreCustomURLSchemesParams = await CoreLoginHelper.validateBrowserSSOLogin(url);
+
+        data.isSSOToken = true;
+        data.isAuthenticationURL = true;
+
+        return data;
+    }
+
+    /**
+     * Go to page to add a site, or open a browser if SSO.
+     *
+     * @param data URL data.
+     * @param checkResponse Result of checkSite.
+     * @return Promise resolved when done.
+     */
+    protected async goToAddSite(data: CoreCustomURLSchemesParams, checkResponse: CoreSiteCheckResponse): Promise<void> {
+        const ssoNeeded = CoreLoginHelper.isSSOLoginNeeded(checkResponse.code);
+        const pageParams = {
+            siteUrl: checkResponse.siteUrl,
+            username: data.username,
+            urlToOpen: data.redirect,
+            siteConfig: checkResponse.config,
+        };
+        let hasSitePluginsLoaded = false;
+
+        if (CoreSites.isLoggedIn()) {
+            // Ask the user before changing site.
+            await CoreDomUtils.showConfirm(Translate.instant('core.contentlinks.confirmurlothersite'));
+
+            if (!ssoNeeded) {
+                hasSitePluginsLoaded = CoreSitePlugins.hasSitePluginsLoaded;
+                if (hasSitePluginsLoaded) {
+                    // Store the redirect since logout will restart the app.
+                    CoreApp.storeRedirect(CoreConstants.NO_SITE_ID, '/login/credentials', pageParams);
+                }
+
+                await CoreSites.logout();
+            }
+        }
+
+        if (ssoNeeded) {
+            CoreLoginHelper.confirmAndOpenBrowserForSSOLogin(
+                checkResponse.siteUrl,
+                checkResponse.code,
+                checkResponse.service,
+                checkResponse.config?.launchurl,
+            );
+        } else if (!hasSitePluginsLoaded) {
+            await CoreNavigator.navigateToLoginCredentials(pageParams);
+        }
+    }
+
+    /**
+     * Check whether a URL is a custom URL scheme.
+     *
+     * @param url URL to check.
+     * @return Whether it's a custom URL scheme.
+     */
+    isCustomURL(url: string): boolean {
+        if (!url) {
+            return false;
+        }
+
+        return url.indexOf(CoreConstants.CONFIG.customurlscheme + '://') != -1;
+    }
+
+    /**
+     * Check whether a URL is a custom URL scheme with the "link" param (deprecated).
+     *
+     * @param url URL to check.
+     * @return Whether it's a custom URL scheme.
+     */
+    isCustomURLLink(url: string): boolean {
+        if (!url) {
+            return false;
+        }
+
+        return url.indexOf(CoreConstants.CONFIG.customurlscheme + '://link=') != -1;
+    }
+
+    /**
+     * Check whether a URL is a custom URL scheme with a "token" param (deprecated).
+     *
+     * @param url URL to check.
+     * @return Whether it's a custom URL scheme.
+     */
+    isCustomURLToken(url: string): boolean {
+        if (!url) {
+            return false;
+        }
+
+        return url.indexOf(CoreConstants.CONFIG.customurlscheme + '://token=') != -1;
+    }
+
+    /**
+     * Remove the scheme from a custom URL.
+     *
+     * @param url URL to treat.
+     * @return URL without scheme.
+     */
+    removeCustomURLScheme(url: string): string {
+        return url.replace(CoreConstants.CONFIG.customurlscheme + '://', '');
+    }
+
+    /**
+     * Remove the scheme and the "link=" prefix from a link custom URL.
+     *
+     * @param url URL to treat.
+     * @return URL without scheme and prefix.
+     */
+    removeCustomURLLinkScheme(url: string): string {
+        return url.replace(CoreConstants.CONFIG.customurlscheme + '://link=', '');
+    }
+
+    /**
+     * Remove the scheme and the "token=" prefix from a token custom URL.
+     *
+     * @param url URL to treat.
+     * @return URL without scheme and prefix.
+     */
+    removeCustomURLTokenScheme(url: string): string {
+        return url.replace(CoreConstants.CONFIG.customurlscheme + '://token=', '');
+    }
+
+    /**
+     * Treat error returned by handleCustomURL.
+     *
+     * @param error Error data.
+     */
+    treatHandleCustomURLError(error: CoreCustomURLSchemesHandleError): void {
+        if (error.error == 'Duplicated') {
+            // Duplicated request
+        } else if (CoreUtils.isWebServiceError(error.error) && error.data && error.data.isSSOToken) {
+            // An error occurred, display the error and logout the user.
+            CoreLoginHelper.treatUserTokenError(error.data.siteUrl, <CoreWSError> error.error);
+            CoreSites.logout();
+        } else {
+            CoreDomUtils.showErrorModalDefault(error.error, Translate.instant('core.login.invalidsite'));
+        }
+    }
+
+}
+
+/**
+ * Error returned by handleCustomURL.
+ */
+export class CoreCustomURLSchemesHandleError extends CoreError {
+
+    /**
+     * Constructor.
+     *
+     * @param error The error message or object.
+     * @param data Data obtained from the URL (if any).
+     */
+    constructor(public error: string | CoreError | CoreTextErrorObject | null, public data?: CoreCustomURLSchemesParams) {
+        super(CoreTextUtils.getErrorMessageFromError(error));
+    }
+
+}
+
+export const CoreCustomURLSchemes = makeSingleton(CoreCustomURLSchemesProvider);
+
+/**
+ * All params that can be in a custom URL scheme.
+ */
+export interface CoreCustomURLSchemesParams extends CoreLoginSSOData {
+
+    /**
+     * Username.
+     */
+    username?: string;
+
+    /**
+     * URL to open once authenticated.
+     */
+    redirect?: string;
+
+    /**
+     * Whether it's an SSO token URL.
+     */
+    isSSOToken?: boolean;
+
+    /**
+     * Whether the URL is meant to perform an authentication.
+     */
+    isAuthenticationURL?: boolean;
+}

src/core/services/utils/text.ts

@@ -118,21 +118,29 @@ export class CoreTextUtilsProvider {
      * @param text Text to add.
      * @return Modified error.
      */
-    addTextToError(error: string | CoreTextErrorObject, text: string): string | CoreTextErrorObject {
+    addTextToError(error: string | CoreError | CoreTextErrorObject | undefined | null, text: string): string | CoreTextErrorObject {
         if (typeof error == 'string') {
             return error + text;
         }
 
-        if (error) {
-            if (typeof error.message == 'string') {
-                error.message += text;
-            } else if (typeof error.error == 'string') {
-                error.error += text;
-            } else if (typeof error.content == 'string') {
-                error.content += text;
-            } else if (typeof error.body == 'string') {
-                error.body += text;
-            }
+        if (error instanceof CoreError) {
+            error.message += text;
+
+            return error;
+        }
+
+        if (!error) {
+            return text;
+        }
+
+        if (typeof error.message == 'string') {
+            error.message += text;
+        } else if (typeof error.error == 'string') {
+            error.error += text;
+        } else if (typeof error.content == 'string') {
+            error.content += text;
+        } else if (typeof error.body == 'string') {
+            error.body += text;
         }
 
         return error;
@@ -522,10 +530,10 @@ export class CoreTextUtilsProvider {
     /**
      * Get the error message from an error object.
      *
-     * @param error Error object.
+     * @param error Error.
      * @return Error message, undefined if not found.
      */
-    getErrorMessageFromError(error?: string | CoreError | CoreTextErrorObject): string | undefined {
+    getErrorMessageFromError(error?: string | CoreError | CoreTextErrorObject | null): string | undefined {
         if (typeof error == 'string') {
             return error;
         }
@@ -534,7 +542,11 @@ export class CoreTextUtilsProvider {
             return error.message;
         }
 
-        return error && (error.message || error.error || error.content || error.body);
+        if (!error) {
+            return undefined;
+        }
+
+        return error.message || error.error || error.content || error.body;
     }
 
     /**

src/core/services/utils/url.ts

@@ -362,7 +362,7 @@ export class CoreUrlUtilsProvider {
      * @param url URL to treat.
      * @return Username. Undefined if no username found.
      */
-    getUsernameFromUrl(url: string): string | void {
+    getUsernameFromUrl(url: string): string | undefined {
         if (url.indexOf('@') > -1) {
             // Get URL without protocol.
             const withoutProtocol = url.replace(/^[^?@/]*:\/\//, '');

src/core/services/utils/utils.ts

@@ -26,9 +26,11 @@ import { CoreDomUtils } from '@services/utils/dom';
 import { CoreMimetypeUtils } from '@services/utils/mimetype';
 import { CoreTextUtils } from '@services/utils/text';
 import { CoreWSError } from '@classes/errors/wserror';
-import { makeSingleton, Clipboard, InAppBrowser, FileOpener, WebIntent, QRScanner, Translate } from '@singletons';
+import { makeSingleton, Clipboard, InAppBrowser, FileOpener, WebIntent, QRScanner, Translate, ModalController } from '@singletons';
 import { CoreLogger } from '@singletons/logger';
 import { CoreFileSizeSum } from '@services/plugin-file-delegate';
+import { CoreViewerQRScannerComponent } from '@features/viewer/components/qr-scanner/qr-scanner';
+import { CoreCanceledError } from '@classes/errors/cancelederror';
 
 type TreeNode<T> = T & { children: TreeNode<T>[] };
 
@@ -1489,12 +1491,20 @@ export class CoreUtilsProvider {
      * @param title Title of the modal. Defaults to "QR reader".
      * @return Promise resolved with the captured text or undefined if cancelled or error.
      */
-    // eslint-disable-next-line @typescript-eslint/no-unused-vars
-    scanQR(title?: string): Promise<string> {
-        // eslint-disable-next-line @typescript-eslint/no-unused-vars
-        return new Promise((resolve, reject): void => {
-            // @todo
+    async scanQR(title?: string): Promise<string> {
+        const modal = await ModalController.create({
+            component: CoreViewerQRScannerComponent,
+            cssClass: 'core-modal-fullscreen',
+            componentProps: {
+                title,
+            },
         });
+
+        await modal.present();
+
+        const result = await modal.onWillDismiss();
+
+        return result.data;
     }
 
     /**
@@ -1503,12 +1513,6 @@ export class CoreUtilsProvider {
      * @return Promise resolved with the QR string, rejected if error or cancelled.
      */
     async startScanQR(): Promise<string | undefined> {
-        try {
-            return this.startScanQR();
-        } catch (error) {
-            // do nothing
-        }
-
         if (!CoreApp.isMobile()) {
             return Promise.reject('QRScanner isn\'t available in browser.');
         }
@@ -1580,7 +1584,7 @@ export class CoreUtilsProvider {
         } else if (typeof data != 'undefined') {
             this.qrScanData.deferred.resolve(data as string);
         } else {
-            this.qrScanData.deferred.reject(CoreDomUtils.createCanceledError());
+            this.qrScanData.deferred.reject(new CoreCanceledError());
         }
 
         delete this.qrScanData;

src/core/singletons/events.ts

@@ -45,6 +45,7 @@ export interface CoreEventsData {
     [CoreEvents.COMPLETION_MODULE_VIEWED]: CoreEventCompletionModuleViewedData;
     [CoreEvents.SECTION_STATUS_CHANGED]: CoreEventSectionStatusChangedData;
     [CoreEvents.ACTIVITY_DATA_SENT]: CoreEventActivityDataSentData;
+    [CoreEvents.IAB_LOAD_START]: InAppBrowserEvent;
 };
 
 /*

src/theme/theme.base.scss

@@ -454,3 +454,14 @@ ion-button.core-button-select {
 .core-iframe-offline-disabled {
     display: none !important;
 }
+
+.core-scanning-qr {
+    .ion-page, .modal-wrapper {
+        background-color: transparent !important;
+        --background: transparent;
+    }
+
+    ion-content, ion-backdrop, ion-modal:not(.core-modal-fullscreen), ion-tabs {
+        display: none !important;
+    }
+}