Destroy dynamically generated components in onDestroy & replace deprecated createComponent

src/app/admin/admin-search-page/admin-search-results/admin-search-result-grid-element/item-search-result/item-admin-search-result-grid-element.component.ts

@@ -1,4 +1,4 @@
-import { Component, ComponentFactoryResolver, ElementRef, OnInit, ViewChild } from '@angular/core';
+import { Component, ElementRef, OnInit, ViewChild, ComponentRef, OnDestroy } from '@angular/core';
 import { Item } from '../../../../../core/shared/item.model';
 import { ViewMode } from '../../../../../core/shared/view-mode.model';
 import {
@@ -13,6 +13,7 @@ import { BitstreamDataService } from '../../../../../core/data/bitstream-data.se
 import { GenericConstructor } from '../../../../../core/shared/generic-constructor';
 import { ListableObjectDirective } from '../../../../../shared/object-collection/shared/listable-object/listable-object.directive';
 import { ThemeService } from '../../../../../shared/theme-support/theme.service';
+import { hasValue } from '../../../../../shared/empty.util';
 
 @listableObjectComponent(ItemSearchResult, ViewMode.GridElement, Context.AdminSearch)
 @Component({
@@ -23,15 +24,16 @@ import { ThemeService } from '../../../../../shared/theme-support/theme.service'
 /**
  * The component for displaying a list element for an item search result on the admin search page
  */
-export class ItemAdminSearchResultGridElementComponent extends SearchResultGridElementComponent<ItemSearchResult, Item> implements OnInit {
+export class ItemAdminSearchResultGridElementComponent extends SearchResultGridElementComponent<ItemSearchResult, Item> implements OnDestroy, OnInit {
   @ViewChild(ListableObjectDirective, { static: true }) listableObjectDirective: ListableObjectDirective;
   @ViewChild('badges', { static: true }) badges: ElementRef;
   @ViewChild('buttons', { static: true }) buttons: ElementRef;
 
+  protected compRef: ComponentRef<Component>;
+
   constructor(protected truncatableService: TruncatableService,
               protected bitstreamDataService: BitstreamDataService,
               private themeService: ThemeService,
-              private componentFactoryResolver: ComponentFactoryResolver
   ) {
     super(truncatableService, bitstreamDataService);
   }
@@ -41,23 +43,32 @@ export class ItemAdminSearchResultGridElementComponent extends SearchResultGridE
    */
   ngOnInit(): void {
     super.ngOnInit();
-    const componentFactory = this.componentFactoryResolver.resolveComponentFactory(this.getComponent());
+    const component: GenericConstructor<Component> = this.getComponent();
 
     const viewContainerRef = this.listableObjectDirective.viewContainerRef;
     viewContainerRef.clear();
 
-    const componentRef = viewContainerRef.createComponent(
+    this.compRef = viewContainerRef.createComponent(
-      componentFactory,
+      component, {
-      0,
+        index: 0,
-      undefined,
+        injector: undefined,
-      [
+        projectableNodes: [
           [this.badges.nativeElement],
-        [this.buttons.nativeElement]
+          [this.buttons.nativeElement],
-      ]);
+        ],
-    (componentRef.instance as any).object = this.object;
+      },
-    (componentRef.instance as any).index = this.index;
+    );
-    (componentRef.instance as any).linkType = this.linkType;
+    (this.compRef.instance as any).object = this.object;
-    (componentRef.instance as any).listID = this.listID;
+    (this.compRef.instance as any).index = this.index;
+    (this.compRef.instance as any).linkType = this.linkType;
+    (this.compRef.instance as any).listID = this.listID;
+  }
+
+  ngOnDestroy(): void {
+    if (hasValue(this.compRef)) {
+      this.compRef.destroy();
+      this.compRef = undefined;
+    }
   }
 
   /**

src/app/admin/admin-workflow-page/admin-workflow-search-results/admin-workflow-search-result-grid-element/workflow-item/workflow-item-search-result-admin-workflow-grid-element.component.ts

@@ -1,4 +1,4 @@
-import { Component, ComponentFactoryResolver, ElementRef, ViewChild } from '@angular/core';
+import { Component, ElementRef, ViewChild, ComponentRef, OnDestroy, OnInit } from '@angular/core';
 import { Item } from '../../../../../core/shared/item.model';
 import { ViewMode } from '../../../../../core/shared/view-mode.model';
 import {
@@ -23,6 +23,7 @@ import {
 import { take } from 'rxjs/operators';
 import { WorkflowItemSearchResult } from '../../../../../shared/object-collection/shared/workflow-item-search-result.model';
 import { ThemeService } from '../../../../../shared/theme-support/theme.service';
+import { hasValue } from '../../../../../shared/empty.util';
 
 @listableObjectComponent(WorkflowItemSearchResult, ViewMode.GridElement, Context.AdminWorkflowSearch)
 @Component({
@@ -33,7 +34,7 @@ import { ThemeService } from '../../../../../shared/theme-support/theme.service'
 /**
  * The component for displaying a grid element for an workflow item on the admin workflow search page
  */
-export class WorkflowItemSearchResultAdminWorkflowGridElementComponent extends SearchResultGridElementComponent<WorkflowItemSearchResult, WorkflowItem> {
+export class WorkflowItemSearchResultAdminWorkflowGridElementComponent extends SearchResultGridElementComponent<WorkflowItemSearchResult, WorkflowItem> implements OnDestroy, OnInit {
   /**
    * Directive used to render the dynamic component in
    */
@@ -54,8 +55,9 @@ export class WorkflowItemSearchResultAdminWorkflowGridElementComponent extends S
    */
   public item$: Observable<Item>;
 
+  protected compRef: ComponentRef<Component>;
+
   constructor(
-    private componentFactoryResolver: ComponentFactoryResolver,
     private linkService: LinkService,
     protected truncatableService: TruncatableService,
     private themeService: ThemeService,
@@ -73,28 +75,37 @@ export class WorkflowItemSearchResultAdminWorkflowGridElementComponent extends S
     this.dso = this.linkService.resolveLink(this.dso, followLink('item'));
     this.item$ = (this.dso.item as Observable<RemoteData<Item>>).pipe(getAllSucceededRemoteData(), getRemoteDataPayload());
     this.item$.pipe(take(1)).subscribe((item: Item) => {
-        const componentFactory = this.componentFactoryResolver.resolveComponentFactory(this.getComponent(item));
+        const component: GenericConstructor<Component> = this.getComponent(item);
 
         const viewContainerRef = this.listableObjectDirective.viewContainerRef;
         viewContainerRef.clear();
 
-        const componentRef = viewContainerRef.createComponent(
+        this.compRef = viewContainerRef.createComponent(
-          componentFactory,
+          component, {
-          0,
+            index: 0,
-          undefined,
+            injector: undefined,
-          [
+            projectableNodes: [
               [this.badges.nativeElement],
-            [this.buttons.nativeElement]
+              [this.buttons.nativeElement],
-          ]);
+            ],
-        (componentRef.instance as any).object = item;
+          },
-        (componentRef.instance as any).index = this.index;
+        );
-        (componentRef.instance as any).linkType = this.linkType;
+        (this.compRef.instance as any).object = item;
-        (componentRef.instance as any).listID = this.listID;
+        (this.compRef.instance as any).index = this.index;
-        componentRef.changeDetectorRef.detectChanges();
+        (this.compRef.instance as any).linkType = this.linkType;
+        (this.compRef.instance as any).listID = this.listID;
+      this.compRef.changeDetectorRef.detectChanges();
       }
     );
   }
 
+  ngOnDestroy(): void {
+    if (hasValue(this.compRef)) {
+      this.compRef.destroy();
+      this.compRef = undefined;
+    }
+  }
+
   /**
    * Fetch the component depending on the item's entity type, view mode and context
    * @returns {GenericConstructor<Component>}

src/app/shared/loading/themed-loading.component.ts

@@ -1,4 +1,4 @@
-import { Component, Input, ComponentFactoryResolver, ChangeDetectorRef } from '@angular/core';
+import { Component, Input, ChangeDetectorRef } from '@angular/core';
 import { ThemedComponent } from '../theme-support/themed.component';
 import { LoadingComponent } from './loading.component';
 import { ThemeService } from '../theme-support/theme.service';
@@ -20,11 +20,10 @@ export class ThemedLoadingComponent extends ThemedComponent<LoadingComponent> {
   protected inAndOutputNames: (keyof LoadingComponent & keyof this)[] = ['message', 'showMessage', 'spinner'];
 
   constructor(
-    protected resolver: ComponentFactoryResolver,
     protected cdr: ChangeDetectorRef,
     protected themeService: ThemeService
   ) {
-    super(resolver, cdr, themeService);
+    super(cdr, themeService);
   }
 
   protected getComponentName(): string {

src/app/shared/metadata-representation/metadata-representation-loader.component.ts

@@ -1,4 +1,4 @@
-import { Component, ComponentFactoryResolver, Inject, Input, OnInit, ViewChild } from '@angular/core';
+import { Component, Inject, Input, OnInit, ViewChild, ComponentRef, OnDestroy } from '@angular/core';
 import {
   MetadataRepresentation,
   MetadataRepresentationType
@@ -19,8 +19,9 @@ import { ThemeService } from '../theme-support/theme.service';
 /**
  * Component for determining what component to use depending on the item's entity type (dspace.entity.type), its metadata representation and, optionally, its context
  */
-export class MetadataRepresentationLoaderComponent implements OnInit {
+export class MetadataRepresentationLoaderComponent implements OnDestroy, OnInit {
   private componentRefInstance: MetadataRepresentationListElementComponent;
+  protected compRef: ComponentRef<MetadataRepresentationListElementComponent>;
 
   /**
    * The item or metadata to determine the component for
@@ -47,7 +48,6 @@ export class MetadataRepresentationLoaderComponent implements OnInit {
   @ViewChild(MetadataRepresentationDirective, {static: true}) mdRepDirective: MetadataRepresentationDirective;
 
   constructor(
-    private componentFactoryResolver: ComponentFactoryResolver,
     private themeService: ThemeService,
     @Inject(METADATA_REPRESENTATION_COMPONENT_FACTORY) private getMetadataRepresentationComponent: (entityType: string, mdRepresentationType: MetadataRepresentationType, context: Context, theme: string) => GenericConstructor<any>,
   ) {
@@ -57,16 +57,23 @@ export class MetadataRepresentationLoaderComponent implements OnInit {
    * Set up the dynamic child component
    */
   ngOnInit(): void {
-    const componentFactory = this.componentFactoryResolver.resolveComponentFactory(this.getComponent());
+    const component: GenericConstructor<MetadataRepresentationListElementComponent> = this.getComponent();
 
     const viewContainerRef = this.mdRepDirective.viewContainerRef;
     viewContainerRef.clear();
 
-    const componentRef = viewContainerRef.createComponent(componentFactory);
+    this.compRef = viewContainerRef.createComponent(component);
-    this.componentRefInstance = componentRef.instance as MetadataRepresentationListElementComponent;
+    this.componentRefInstance = this.compRef.instance as MetadataRepresentationListElementComponent;
     this.componentRefInstance.metadataRepresentation = this.mdRepresentation;
   }
 
+  ngOnDestroy(): void {
+    if (hasValue(this.compRef)) {
+      this.compRef.destroy();
+      this.compRef = undefined;
+    }
+  }
+
   /**
    * Fetch the component depending on the item's entity type, metadata representation type and context
    * @returns {string}

src/app/shared/mydspace-actions/claimed-task/switcher/claimed-task-actions-loader.component.ts

@@ -1,12 +1,11 @@
 import {
   Component,
-  ComponentFactoryResolver,
   EventEmitter,
   Input,
   OnDestroy,
   OnInit,
   Output,
-  ViewChild
+  ViewChild, ComponentRef
 } from '@angular/core';
 import { getComponentByWorkflowTaskOption } from './claimed-task-actions-decorator';
 import { ClaimedTask } from '../../../../core/tasks/models/claimed-task-object.model';
@@ -64,8 +63,7 @@ export class ClaimedTaskActionsLoaderComponent implements OnInit, OnDestroy {
    */
   protected subs: Subscription[] = [];
 
-  constructor(private componentFactoryResolver: ComponentFactoryResolver) {
+  protected compRef: ComponentRef<Component>;
-  }
 
   /**
    * Fetch, create and initialize the relevant component
@@ -74,13 +72,11 @@ export class ClaimedTaskActionsLoaderComponent implements OnInit, OnDestroy {
 
     const comp = this.getComponentByWorkflowTaskOption(this.option);
     if (hasValue(comp)) {
-      const componentFactory = this.componentFactoryResolver.resolveComponentFactory(comp);
-
       const viewContainerRef = this.claimedTaskActionsDirective.viewContainerRef;
       viewContainerRef.clear();
 
-      const componentRef = viewContainerRef.createComponent(componentFactory);
+      this.compRef = viewContainerRef.createComponent(comp);
-      const componentInstance = (componentRef.instance as ClaimedTaskActionsAbstractComponent);
+      const componentInstance = (this.compRef.instance as ClaimedTaskActionsAbstractComponent);
       componentInstance.item = this.item;
       componentInstance.object = this.object;
       componentInstance.workflowitem = this.workflowitem;
@@ -98,6 +94,10 @@ export class ClaimedTaskActionsLoaderComponent implements OnInit, OnDestroy {
    * Unsubscribe from open subscriptions
    */
   ngOnDestroy(): void {
+    if (hasValue(this.compRef)) {
+      this.compRef.destroy();
+      this.compRef = undefined;
+    }
     this.subs
       .filter((subscription) => hasValue(subscription))
       .forEach((subscription) => subscription.unsubscribe());

src/app/shared/object-collection/shared/listable-object/listable-object-component-loader.component.ts

@@ -23,7 +23,7 @@ import { getListableObjectComponent } from './listable-object.decorator';
 import { GenericConstructor } from '../../../../core/shared/generic-constructor';
 import { ListableObjectDirective } from './listable-object.directive';
 import { CollectionElementLinkType } from '../../collection-element-link.type';
-import { hasValue, isNotEmpty } from '../../../empty.util';
+import { hasValue, isNotEmpty, hasNoValue } from '../../../empty.util';
 import { DSpaceObject } from '../../../../core/shared/dspace-object.model';
 import { ThemeService } from '../../../theme-support/theme.service';
 
@@ -141,8 +141,10 @@ export class ListableObjectComponentLoaderComponent implements OnInit, OnChanges
    * Setup the dynamic child component
    */
   ngOnInit(): void {
+    if (hasNoValue(this.compRef)) {
       this.instantiateComponent(this.object);
     }
+  }
 
   /**
    * Whenever the inputs change, update the inputs of the dynamic component
@@ -153,7 +155,11 @@ export class ListableObjectComponentLoaderComponent implements OnInit, OnChanges
     }
   }
 
-  ngOnDestroy() {
+  ngOnDestroy(): void {
+    if (hasValue(this.compRef)) {
+      this.compRef.destroy();
+      this.compRef = undefined;
+    }
     this.subs
       .filter((subscription) => hasValue(subscription))
       .forEach((subscription) => subscription.unsubscribe());

src/app/shared/theme-support/themed.component.ts

@@ -6,7 +6,6 @@ import {
   SimpleChanges,
   OnInit,
   OnDestroy,
-  ComponentFactoryResolver,
   ChangeDetectorRef,
   OnChanges
 } from '@angular/core';
@@ -31,7 +30,6 @@ export abstract class ThemedComponent<T> implements OnInit, OnDestroy, OnChanges
   protected inAndOutputNames: (keyof T & keyof this)[] = [];
 
   constructor(
-    protected resolver: ComponentFactoryResolver,
     protected cdr: ChangeDetectorRef,
     protected themeService: ThemeService
   ) {
@@ -87,8 +85,7 @@ export abstract class ThemedComponent<T> implements OnInit, OnDestroy, OnChanges
         }
       }),
     ).subscribe((constructor: GenericConstructor<T>) => {
-      const factory = this.resolver.resolveComponentFactory(constructor);
+      this.compRef = this.vcr.createComponent(constructor);
-      this.compRef = this.vcr.createComponent(factory);
       this.connectInputsAndOutputs();
       this.cdr.markForCheck();
     });