Fix mix editor did not get the materials from the correct location in update mode

src/app/modules/recipes/mix/mix.ts

@@ -27,7 +27,7 @@ abstract class _BaseMixPage extends SubscribingComponent {
     protected mixService: MixService,
     private recipeService: RecipeService,
     private materialTypeService: MaterialTypeService,
-    private materialService: MaterialService,
+    protected materialService: MaterialService,
     errorService: ErrorService,
     router: Router,
     activatedRoute: ActivatedRoute
@@ -50,13 +50,15 @@ abstract class _BaseMixPage extends SubscribingComponent {
 
   set recipe(recipe: Recipe) {
     this._recipe = recipe
-    this.materials$ = this.materialService.getAllForMixCreation(recipe.id)
+    this.materials$ = this.fetchMaterials(recipe.id)
   }
 
   get recipe(): Recipe {
     return this._recipe
   }
 
+  protected abstract fetchMaterials(recipeId: number): Observable<Material[]>
+
   abstract submit(dto: MixSaveDto)
 }
 
@@ -65,6 +67,10 @@ abstract class _BaseMixPage extends SubscribingComponent {
   templateUrl: 'add.html'
 })
 export class MixAdd extends _BaseMixPage {
+  protected fetchMaterials(recipeId: number): Observable<Material[]> {
+    return this.materialService.getAllForMixCreation(recipeId)
+  }
+
   submit(dto: MixSaveDto) {
     this.subscribeAndNavigate(
       this.mixService.saveDto(dto),
@@ -80,21 +86,27 @@ export class MixAdd extends _BaseMixPage {
 export class MixEdit extends _BaseMixPage {
   mix: Mix
 
+  private mixId: number
+
   ngOnInit() {
     super.ngOnInit()
 
+    this.mixId = this.urlUtils.parseIntUrlParam('id')
+
     this.fetchMix()
   }
 
   private fetchMix() {
-    const mixId = this.urlUtils.parseIntUrlParam('id')
-
     this.subscribe(
-      this.mixService.getById(mixId),
+      this.mixService.getById(this.mixId),
       mix => this.mix = mix
     )
   }
 
+  protected fetchMaterials(recipeId: number): Observable<Material[]> {
+    return this.materialService.getAllForMixUpdate(this.mixId)
+  }
+
   submit(dto: MixSaveDto) {
     this.subscribeAndNavigate(
       this.mixService.updateDto({...dto, id: this.mix.id}),