MOBILE-3651 core: Fix scroll to element function

src/addons/mod/quiz/components/preflight-modal/preflight-modal.ts

@@ -47,6 +47,7 @@ export class AddonModQuizPreflightModalComponent implements OnInit {
 
     constructor(
         formBuilder: FormBuilder,
+        protected elementRef: ElementRef,
     ) {
         // Create an empty form group. The controls will be added by the access rules components.
         this.preflightForm = formBuilder.group({});
@@ -115,7 +116,12 @@ export class AddonModQuizPreflightModalComponent implements OnInit {
 
         if (!this.preflightForm.valid) {
             // Form not valid. Scroll to the first element with errors.
-            if (!CoreDomUtils.instance.scrollToInputError(this.content)) {
+            const hasScrolled = CoreDomUtils.instance.scrollToInputError(
+                this.elementRef.nativeElement,
+                this.content,
+            );
+
+            if (!hasScrolled) {
                 // Input not found, show an error modal.
                 CoreDomUtils.instance.showErrorModal('core.errorinvalidform', true);
             }

src/addons/mod/quiz/pages/player/player.ts

@@ -681,9 +681,11 @@ export class AddonModQuizPlayerPage implements OnInit, OnDestroy {
      * @param slot Slot of the question to scroll to.
      */
     protected scrollToQuestion(slot: number): void {
-        if (this.content) {
-            CoreDomUtils.instance.scrollToElementBySelector(this.content, '#addon-mod_quiz-question-' + slot);
-        }
+        CoreDomUtils.instance.scrollToElementBySelector(
+            this.elementRef.nativeElement,
+            this.content,
+            '#addon-mod_quiz-question-' + slot,
+        );
     }
 
     /**

src/core/directives/link.ts

@@ -104,7 +104,11 @@ export class CoreLinkDirective implements OnInit {
         if (href.charAt(0) == '#') {
             // Look for id or name.
             href = href.substr(1);
-            CoreDomUtils.instance.scrollToElementBySelector(this.content, '#' + href + ', [name=\'' + href + '\']');
+            CoreDomUtils.instance.scrollToElementBySelector(
+                this.element.closest('ion-content'),
+                this.content,
+                `#${href}, [name='${href}']`,
+            );
 
             return;
         }

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

@@ -25,6 +25,7 @@ import {
     QueryList,
     Type,
     ViewChild,
+    ElementRef,
 } from '@angular/core';
 
 import { CoreSites } from '@services/sites';
@@ -111,6 +112,7 @@ export class CoreCourseFormatComponent implements OnInit, OnChanges, OnDestroy {
 
     constructor(
         protected content: IonContent,
+        protected elementRef: ElementRef,
     ) {
         // Pass this instance to all components so they can use its methods and properties.
         this.data.coreCourseFormatComponent = this;
@@ -402,7 +404,11 @@ export class CoreCourseFormatComponent implements OnInit, OnChanges, OnDestroy {
 
         if (this.moduleId && typeof previousValue == 'undefined') {
             setTimeout(() => {
-                CoreDomUtils.instance.scrollToElementBySelector(this.content, '#core-course-module-' + this.moduleId);
+                CoreDomUtils.instance.scrollToElementBySelector(
+                    this.elementRef.nativeElement,
+                    this.content,
+                    '#core-course-module-' + this.moduleId,
+                );
             }, 200);
         } else {
             this.content.scrollToTop(0);

src/core/features/login/pages/email-signup/email-signup.ts

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-import { Component, ViewChild, ElementRef, OnInit } from '@angular/core';
+import { Component, ViewChild, ElementRef, OnInit, ChangeDetectorRef } from '@angular/core';
 import { FormBuilder, FormGroup, Validators, FormControl } from '@angular/forms';
 import { IonContent, IonRefresher } from '@ionic/angular';
 
@@ -81,6 +81,8 @@ export class CoreLoginEmailSignupPage implements OnInit {
 
     constructor(
         protected fb: FormBuilder,
+        protected elementRef: ElementRef,
+        protected changeDetector: ChangeDetectorRef,
     ) {
         // Create the ageVerificationForm.
         this.ageVerificationForm = this.fb.group({
@@ -272,8 +274,17 @@ export class CoreLoginEmailSignupPage implements OnInit {
         e.stopPropagation();
 
         if (!this.signupForm.valid || (this.settings?.recaptchapublickey && !this.captcha.recaptcharesponse)) {
-            // Form not valid. Scroll to the first element with errors.
-            const errorFound = await CoreDomUtils.instance.scrollToInputError(this.content);
+            // Form not valid. Mark all controls as dirty to display errors.
+            for (const name in this.signupForm.controls) {
+                this.signupForm.controls[name].markAsDirty();
+            }
+            this.changeDetector.detectChanges();
+
+            // Scroll to the first element with errors.
+            const errorFound = CoreDomUtils.instance.scrollToInputError(
+                this.elementRef.nativeElement,
+                this.content,
+            );
 
             if (!errorFound) {
                 // Input not found, show an error modal.

src/core/services/utils/dom.ts

@@ -1119,24 +1119,26 @@ export class CoreDomUtilsProvider {
     /**
      * Scroll to a certain element using a selector to find it.
      *
+     * @param container The element that contains the element that must be scrolled.
      * @param content The content that must be scrolled.
      * @param selector Selector to find the element to scroll to.
      * @param scrollParentClass Parent class where to stop calculating the position. Default inner-scroll.
      * @param duration Duration of the scroll animation in milliseconds.
      * @return True if the element is found, false otherwise.
      */
-    async scrollToElementBySelector(
-        content: IonContent,
+    scrollToElementBySelector(
+        container: HTMLElement | null,
+        content: IonContent | undefined,
         selector: string,
         scrollParentClass?: string,
         duration?: number,
-    ): Promise<boolean> {
-        // @todo: This function is broken. Scroll element cannot be used because it uses shadow DOM so querySelector returns null.
-        // Also, traversing using parentElement doesn't work either, offsetParent isn't part of the parentElement tree.
-        try {
-            const scrollElement = await content.getScrollElement();
+    ): boolean {
+        if (!container || !content) {
+            return false;
+        }
 
-            const position = this.getElementXY(scrollElement, selector, scrollParentClass);
+        try {
+            const position = this.getElementXY(container, selector, scrollParentClass);
             if (!position) {
                 return false;
             }
@@ -1152,16 +1154,13 @@ export class CoreDomUtilsProvider {
     /**
      * Search for an input with error (core-input-error directive) and scrolls to it if found.
      *
+     * @param container The element that contains the element that must be scrolled.
      * @param content The content that must be scrolled.
      * @param scrollParentClass Parent class where to stop calculating the position. Default inner-scroll.
      * @return True if the element is found, false otherwise.
      */
-    async scrollToInputError(content?: IonContent, scrollParentClass?: string): Promise<boolean> {
-        if (!content) {
-            return false;
-        }
-
-        return this.scrollToElementBySelector(content, '.core-input-error', scrollParentClass);
+    scrollToInputError(container: HTMLElement | null, content?: IonContent, scrollParentClass?: string): boolean {
+        return this.scrollToElementBySelector(container, content, '.core-input-error', scrollParentClass);
     }
 
     /**