Merge pull request #70 from denis-tsv/feature/constructor-injection-viewmodels

Constructor injection for ViewModels

Author: Sergio0694

samples/MvvmSample.Core/ViewModels/AsyncRelayCommandPageViewModel.cs

@@ -4,12 +4,14 @@
 
 using System.Threading.Tasks;
 using CommunityToolkit.Mvvm.Input;
+using MvvmSample.Core.Services;
 
 namespace MvvmSample.Core.ViewModels;
 
 public class AsyncRelayCommandPageViewModel : SamplePageViewModel
 {
-    public AsyncRelayCommandPageViewModel()
+    public AsyncRelayCommandPageViewModel(IFilesService filesService) 
+        : base(filesService)
     {
         DownloadTextCommand = new AsyncRelayCommand(DownloadTextAsync);
     }

samples/MvvmSample.Core/ViewModels/IocPageViewModel.cs

@@ -2,8 +2,14 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using MvvmSample.Core.Services;
+
 namespace MvvmSample.Core.ViewModels;
 
 public class IocPageViewModel : SamplePageViewModel
 {
+    public IocPageViewModel(IFilesService filesService) 
+        : base(filesService)
+    {
+    }
 }

samples/MvvmSample.Core/ViewModels/MessengerPageViewModel.cs

@@ -7,12 +7,14 @@
 using CommunityToolkit.Mvvm.Input;
 using CommunityToolkit.Mvvm.Messaging;
 using CommunityToolkit.Mvvm.Messaging.Messages;
+using MvvmSample.Core.Services;
 
 namespace MvvmSample.Core.ViewModels;
 
 public class MessengerPageViewModel : SamplePageViewModel
 {
-    public MessengerPageViewModel()
+    public MessengerPageViewModel(IFilesService filesService) 
+        : base(filesService)
     {
         RequestCurrentUsernameCommand = new RelayCommand(RequestCurrentUsername);
         ResetCurrentUsernameCommand = new RelayCommand(ResetCurrentUsername);

samples/MvvmSample.Core/ViewModels/ObservableObjectPageViewModel.cs

@@ -5,12 +5,14 @@
 using System.Threading.Tasks;
 using System.Windows.Input;
 using CommunityToolkit.Mvvm.Input;
+using MvvmSample.Core.Services;
 
 namespace MvvmSample.Core.ViewModels;
 
 public class ObservableObjectPageViewModel : SamplePageViewModel
 {
-    public ObservableObjectPageViewModel()
+    public ObservableObjectPageViewModel(IFilesService filesService) 
+        : base(filesService)
     {
         ReloadTaskCommand = new RelayCommand(ReloadTask);
     }

samples/MvvmSample.Core/ViewModels/RelayCommandPageViewModel.cs

@@ -4,12 +4,14 @@
 
 using System.Windows.Input;
 using CommunityToolkit.Mvvm.Input;
+using MvvmSample.Core.Services;
 
 namespace MvvmSample.Core.ViewModels;
 
 public class RelayCommandPageViewModel : SamplePageViewModel
 {
-    public RelayCommandPageViewModel()
+    public RelayCommandPageViewModel(IFilesService filesService) 
+        : base(filesService)
     {
         IncrementCounterCommand = new RelayCommand(IncrementCounter);
     }

samples/MvvmSample.Core/ViewModels/SamplePageViewModel.cs

@@ -7,7 +7,6 @@
 using System.Text.RegularExpressions;
 using System.Threading.Tasks;
 using CommunityToolkit.Mvvm.ComponentModel;
-using CommunityToolkit.Mvvm.DependencyInjection;
 using CommunityToolkit.Mvvm.Input;
 using MvvmSample.Core.Helpers;
 using MvvmSample.Core.Services;
@@ -22,10 +21,12 @@ public class SamplePageViewModel : ObservableObject
     /// <summary>
     /// The <see cref="IFilesService"/> instance currently in use.
     /// </summary>
-    private readonly IFilesService FilesServices = Ioc.Default.GetRequiredService<IFilesService>();
+    private readonly IFilesService FilesServices;
 
-    public SamplePageViewModel()
+    public SamplePageViewModel(IFilesService filesService)
     {
+        FilesServices = filesService;
+
         LoadDocsCommand = new AsyncRelayCommand<string>(LoadDocsAsync);
     }
 

samples/MvvmSample.Core/ViewModels/Widgets/SubredditWidgetViewModel.cs

@@ -22,12 +22,12 @@ public sealed class SubredditWidgetViewModel : ObservableRecipient
     /// <summary>
     /// Gets the <see cref="IRedditService"/> instance to use.
     /// </summary>
-    private readonly IRedditService RedditService = Ioc.Default.GetRequiredService<IRedditService>();
+    private readonly IRedditService RedditService;
 
     /// <summary>
     /// Gets the <see cref="ISettingsService"/> instance to use.
     /// </summary>
-    private readonly ISettingsService SettingsService = Ioc.Default.GetRequiredService<ISettingsService>();
+    private readonly ISettingsService SettingsService;
 
     /// <summary>
     /// An <see cref="AsyncLock"/> instance to avoid concurrent requests.
@@ -37,8 +37,11 @@ public sealed class SubredditWidgetViewModel : ObservableRecipient
     /// <summary>
     /// Creates a new <see cref="SubredditWidgetViewModel"/> instance.
     /// </summary>
-    public SubredditWidgetViewModel()
+    public SubredditWidgetViewModel(IRedditService redditService, ISettingsService settingsService)
     {
+        RedditService = redditService;
+        SettingsService = settingsService;
+
         LoadPostsCommand = new AsyncRelayCommand(LoadPostsAsync);
 
         selectedSubreddit = SettingsService.GetValue<string>(nameof(SelectedSubreddit)) ?? Subreddits[0];

samples/MvvmSampleUwp/App.xaml.cs

@@ -11,6 +11,8 @@
 using Refit;
 using MvvmSampleUwp.Helpers;
 using MvvmSample.Core.Services;
+using MvvmSample.Core.ViewModels.Widgets;
+using MvvmSample.Core.ViewModels;
 
 namespace MvvmSampleUwp;
 
@@ -41,10 +43,20 @@ protected override void OnLaunched(LaunchActivatedEventArgs e)
 
             // Register services
             Ioc.Default.ConfigureServices(
-                new ServiceCollection()
+                new ServiceCollection()
+                //Services
                 .AddSingleton<IFilesService, FilesService>()
                 .AddSingleton<ISettingsService, SettingsService>()
-                .AddSingleton(RestService.For<IRedditService>("https://www.reddit.com/"))
+                .AddSingleton(RestService.For<IRedditService>("https://www.reddit.com/"))
+                //ViewModels
+                .AddTransient<PostWidgetViewModel>()
+                .AddTransient<SubredditWidgetViewModel>()
+                .AddTransient<AsyncRelayCommandPageViewModel>()
+                .AddTransient<IocPageViewModel>()
+                .AddTransient<MessengerPageViewModel>()
+                .AddTransient<ObservableObjectPageViewModel>()
+                .AddTransient<RelayCommandPageViewModel>()
+                .AddTransient<SamplePageViewModel>()
                 .BuildServiceProvider());
         }
 

samples/MvvmSampleUwp/Views/AsyncRelayCommandPage.xaml

@@ -12,9 +12,6 @@
     xmlns:viewModels="using:MvvmSample.Core.ViewModels"
     NavigationCacheMode="Enabled"
     mc:Ignorable="d">
-    <Page.DataContext>
-        <viewModels:AsyncRelayCommandPageViewModel x:Name="ViewModel" />
-    </Page.DataContext>
     <interactivity:Interaction.Behaviors>
         <core:EventTriggerBehavior EventName="Loaded">
             <core:InvokeCommandAction Command="{x:Bind ViewModel.LoadDocsCommand}" CommandParameter="AsyncRelayCommand" />

samples/MvvmSampleUwp/Views/AsyncRelayCommandPage.xaml.cs

@@ -2,6 +2,8 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using CommunityToolkit.Mvvm.DependencyInjection;
+using MvvmSample.Core.ViewModels;
 using Windows.UI.Xaml.Controls;
 
 namespace MvvmSampleUwp.Views;
@@ -14,5 +16,9 @@ public sealed partial class AsyncRelayCommandPage : Page
     public AsyncRelayCommandPage()
     {
         this.InitializeComponent();
+
+        DataContext = Ioc.Default.GetRequiredService<AsyncRelayCommandPageViewModel>();
     }
+
+    public AsyncRelayCommandPageViewModel ViewModel => (AsyncRelayCommandPageViewModel)DataContext;
 }