Student handleiding added

Models/Product.cs

@@ -1,6 +1,8 @@
 using System;
 using System.Collections.Generic;
+using System.ComponentModel;
 using System.Linq;
+using System.Runtime.CompilerServices;
 using System.Text;
 using System.Threading.Tasks;
 
@@ -8,8 +10,35 @@ namespace MVVM_DEMO.Models
 {
     public class Product
     {
-        public string ProductName { get; set; }
+        private string _productName;
-        public double Price { get; set; }
+        private decimal _productPrice;
+
+        public string ProductName
+        {
+            get => _productName;
+            set
+            {
+                _productName = value;
+                OnPropertyChanged();
+            }
+        }
+
+        public decimal ProductPrice
+        {
+            get => _productPrice;
+            set
+            {
+                _productPrice = value;
+                OnPropertyChanged();
+            }
+        }
+
+        public event PropertyChangedEventHandler PropertyChanged;
+
+        protected void OnPropertyChanged([CallerMemberName] string propertyName = null)
+        {
+            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
+        }
 
     }
 }

ViewModels/MainViewModel.cs

@@ -1,13 +1,14 @@
-using System;
+using MVVM_DEMO.Commands;
+using MVVM_DEMO.Models;
+using System;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
 using System.ComponentModel;
 using System.Linq;
+using System.Runtime.CompilerServices;
 using System.Text;
 using System.Threading.Tasks;
 using System.Windows.Input;
-using MVVM_DEMO.Commands;
-using MVVM_DEMO.Models;
 
 namespace MVVM_DEMO.ViewModels
 {
@@ -16,10 +17,11 @@ namespace MVVM_DEMO.ViewModels
         
     
         private ObservableCollection<Product> _products;
+        private Product _selectedProduct;
 
-        public event PropertyChangedEventHandler? PropertyChanged;
+        public event PropertyChangedEventHandler PropertyChanged;
 
-        public void OnPropertyChanged(string propertyName)
+        public void OnPropertyChanged([CallerMemberName] string propertyName = null)
         {
             PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
         }
@@ -38,18 +40,33 @@ namespace MVVM_DEMO.ViewModels
         // read data
         private  void LoadData()
         {
-            _products.Add(new Product { ProductName = "Product 1", Price = 10.0 });
+            _products.Add(new Product { ProductName = "Product 1",ProductPrice = 10 });
-            _products.Add(new Product { ProductName = "Product 2", Price = 20.0 });
+            _products.Add(new Product { ProductName = "Product 2", ProductPrice = 20 });
-            _products.Add(new Product { ProductName = "Product 3", Price = 30.0 });
+            _products.Add(new Product { ProductName = "Product 3", ProductPrice = 30 });
             Products = _products;
         }
 
 
         // properties
-        public ObservableCollection<Product> Products { get; set; }
+        public ObservableCollection<Product> Products 
+        {
+            get => _products;
+            set
+            {
+                _products = value;
+                OnPropertyChanged();
+            }
+        }
 
-        public string productName { get; set; }
+        public Product SelectedProduct
-        public int productPrice { get; set; }
+        {
+            get => _selectedProduct;
+            set
+            {
+                _selectedProduct = value;
+                OnPropertyChanged();
+            }
+        }
 
         // Commands
         public ICommand AddProductCommand { get; set; }
@@ -63,7 +80,7 @@ namespace MVVM_DEMO.ViewModels
             Products.Add(new Product
             {
                 ProductName = $"Product {Products.Count + 1}",
-                Price = randomPrice
+                ProductPrice = randomPrice
             });
         }
 

Views/MainWindow.xaml

@@ -21,6 +21,7 @@
                       Margin="10"
                       VerticalAlignment="Top"
                       ItemsSource="{Binding Products}"
+                      SelectedItem="{Binding SelectedProduct, Mode=TwoWay}"
                       DisplayMemberPath="ProductName" />
             <Button x:Name="btnAddProduct"
                     Content="Add Product"
@@ -34,12 +35,12 @@
             <TextBox x:Name="txtProductName"
                      Width="200"
                      Height="30"
-                     Text="{Binding productName}" 
+                     Text="{Binding SelectedProduct.ProductName, UpdateSourceTrigger=PropertyChanged}" 
                      />
             <TextBox x:Name="txtProductPrice"
                      Width="200"
                      Height="30"
-                     Text="{Binding productPrice}" />
+                     Text="{Binding SelectedProduct.ProductPrice, UpdateSourceTrigger=PropertyChanged}" />
         </StackPanel>
     </Grid>
 </Window>

Views/MainWindow.xaml.cs

@@ -35,10 +35,11 @@ namespace MVVM_DEMO
             // display selected product details
             if (comboBox.SelectedItem != null && DataContext is MainViewModel viewModel)
             {
-                viewModel.productName = ((Product)comboBox.SelectedItem).ProductName;
+                /*viewModel.productName = ((Product)comboBox.SelectedItem).ProductName;
-                viewModel.productPrice = (int)((Product)comboBox.SelectedItem).Price;
+                viewModel.productPrice = (int)((Product)comboBox.SelectedItem).ProductPrice;
-                viewModel.OnPropertyChanged("productName");
+                viewModel.OnPropertyChanged(nameof(viewModel.productName));
-                viewModel.OnPropertyChanged("productPrice");
+                viewModel.OnPropertyChanged(nameof(viewModel.productPrice));*/
+
             }
         }