From 17daebad8d4109cd3101281e29907121bd8923dc Mon Sep 17 00:00:00 2001
From: Nils Dittberner <nils.dittberner@pta.de>
Date: Wed, 22 Nov 2017 15:23:46 +0100
Subject: [PATCH] 14-166 Improving observables and use subjects, also cleanup

---
 src/app/app.component.html                       |  2 +-
 src/app/header/header.component.html             |  2 +-
 src/app/recipes/recipe.service.ts                |  2 --
 src/app/recipes/recipes.component.ts             | 11 ++---------
 src/app/shopping-list/shopping-list.component.ts | 11 +++++++++--
 src/app/shopping-list/shopping-list.service.ts   |  8 ++++----
 6 files changed, 17 insertions(+), 19 deletions(-)

diff --git a/src/app/app.component.html b/src/app/app.component.html
index 1042b03..01729c9 100644
--- a/src/app/app.component.html
+++ b/src/app/app.component.html
@@ -1,4 +1,4 @@
-<app-header (featureSelected)="onNavigate($event)"></app-header>
+<app-header></app-header>
 <div class="container">
     <div class="row">
         <div class="col-md-12">
diff --git a/src/app/header/header.component.html b/src/app/header/header.component.html
index c10ae21..97ac871 100644
--- a/src/app/header/header.component.html
+++ b/src/app/header/header.component.html
@@ -1,7 +1,7 @@
 <nav class="navbar navbar-default">
     <div class="container-fluid">
         <div class="navbar-header">
-            <a href="#" class="navbar-brand">Recipe Book</a>
+            <a routerLink="/" class="navbar-brand">Recipe Book</a>
         </div>
 
         <div class="navbar-default">
diff --git a/src/app/recipes/recipe.service.ts b/src/app/recipes/recipe.service.ts
index ee376af..9f02c1c 100644
--- a/src/app/recipes/recipe.service.ts
+++ b/src/app/recipes/recipe.service.ts
@@ -5,8 +5,6 @@ import { ShoppingListService } from "../shopping-list/shopping-list.service";
 
 @Injectable()
 export class RecipeService {
-    recipeSelected = new EventEmitter<Recipe>();
-
     private recipes: Recipe[] = [
         new Recipe(
             'A Test Recipe', 
diff --git a/src/app/recipes/recipes.component.ts b/src/app/recipes/recipes.component.ts
index d141413..e63108b 100644
--- a/src/app/recipes/recipes.component.ts
+++ b/src/app/recipes/recipes.component.ts
@@ -1,6 +1,5 @@
 import { Component, OnInit } from '@angular/core';
 
-import { Recipe } from './recipe.model';
 import { RecipeService } from './recipe.service';
 
 @Component({
@@ -10,16 +9,10 @@ import { RecipeService } from './recipe.service';
   providers: [RecipeService]
 })
 export class RecipesComponent implements OnInit {
-  selectedRecipe: Recipe;
-
-  constructor(private recipeService: RecipeService) { }
+  
+  constructor() { }
 
   ngOnInit() {
-    this.recipeService.recipeSelected.subscribe(
-      (recipe: Recipe) => {
-        this.selectedRecipe = recipe;
-      }
-    );
   }
 
 }
diff --git a/src/app/shopping-list/shopping-list.component.ts b/src/app/shopping-list/shopping-list.component.ts
index 1ca7413..11a5599 100644
--- a/src/app/shopping-list/shopping-list.component.ts
+++ b/src/app/shopping-list/shopping-list.component.ts
@@ -1,23 +1,30 @@
 import { Component, OnInit } from '@angular/core';
 import { Ingredient } from '../shared/ingredient.model';
 import { ShoppingListService } from './shopping-list.service';
+import { Subscription } from 'rxjs/Subscription';
+import { OnDestroy } from '@angular/core/src/metadata/lifecycle_hooks';
 
 @Component({
   selector: 'app-shopping-list',
   templateUrl: './shopping-list.component.html',
   styleUrls: ['./shopping-list.component.css']
 })
-export class ShoppingListComponent implements OnInit {
+export class ShoppingListComponent implements OnInit, OnDestroy {
   ingredients: Ingredient[];
+  private subscription: Subscription
 
   constructor(private shoppingListService: ShoppingListService) { }
 
   ngOnInit() {
     this.ingredients = this.shoppingListService.getIngredients();
-    this.shoppingListService.ingredientsChanged.subscribe(
+    this.subscription = this.shoppingListService.ingredientsChanged.subscribe(
       (ingredients: Ingredient[]) => {
         this.ingredients = ingredients;
       }
     );
   }
+
+  ngOnDestroy() {
+    this.subscription.unsubscribe();
+  }
 }
diff --git a/src/app/shopping-list/shopping-list.service.ts b/src/app/shopping-list/shopping-list.service.ts
index fa174ee..c30a2f6 100644
--- a/src/app/shopping-list/shopping-list.service.ts
+++ b/src/app/shopping-list/shopping-list.service.ts
@@ -1,8 +1,8 @@
 import { Ingredient } from "../shared/ingredient.model";
-import { EventEmitter } from "@angular/core";
+import { Subject } from "rxjs/Subject";
 
 export class ShoppingListService {
-    ingredientsChanged = new EventEmitter<Ingredient[]>();
+    ingredientsChanged = new Subject<Ingredient[]>();
     private ingredients: Ingredient[] = [
         new Ingredient('Apples', 5),
         new Ingredient('Tomatoes', 10)
@@ -14,11 +14,11 @@ export class ShoppingListService {
 
     addIngredient(ingredient: Ingredient) {
         this.ingredients.push(ingredient);
-        this.ingredientsChanged.emit(this.ingredients.slice());
+        this.ingredientsChanged.next(this.ingredients.slice());
     }
 
     addIngredients(ingredients: Ingredient[]) {
         this.ingredients.push(...ingredients);
-        this.ingredientsChanged.emit(this.ingredients.slice());
+        this.ingredientsChanged.next(this.ingredients.slice());
     }
 }
\ No newline at end of file