add MessageBox-implementation of DialogService to MvmmLight.Platform NET45

GalaSoft.MvvmLight/GalaSoft.MvvmLight.Platform (NET45)/GalaSoft.MvvmLight.Platform (NET45).csproj

@@ -65,6 +65,7 @@
     <Compile Include="Command\EventToCommand.cs" />
     <Compile Include="Command\IEventArgsConverter.cs" />
     <Compile Include="Threading\DispatcherHelper.cs" />
+    <Compile Include="Views\DialogService.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\GalaSoft.MvvmLight %28PCL%29\GalaSoft.MvvmLight %28PCL%29.csproj">

GalaSoft.MvvmLight/GalaSoft.MvvmLight.Platform (NET45)/Views/DialogService.cs

@@ -0,0 +1,182 @@
+// ****************************************************************************
+// <copyright file="DialogService.cs" company="GalaSoft Laurent Bugnion">
+// Copyright © GalaSoft Laurent Bugnion 2009-2016
+// </copyright>
+// ****************************************************************************
+// <author>Laurent Bugnion</author>
+// <email>laurent@galasoft.ch</email>
+// <date>02.10.2014</date>
+// <project>GalaSoft.MvvmLight.Extras</project>
+// <web>http://www.mvvmlight.net</web>
+// <license>
+// See license.txt in this solution or http://www.galasoft.ch/license_MIT.txt
+// </license>
+// <remarks>
+// Copy of GalaSoft.MvvmLight\GalaSoft.MvvmLight.Platform (WPSL81)\Views\DialogService.cs,
+// only comments updated and null-propagation used for invoking events.
+// </remarks>
+// ****************************************************************************
+
+using System;
+using System.Threading.Tasks;
+using System.Windows;
+using GalaSoft.MvvmLight.Helpers;
+
+namespace GalaSoft.MvvmLight.Views
+{
+    /// <summary>
+    /// An implementation of <see cref="IDialogService"/> allowing
+    /// to display simple dialogs to the user. Note that this class
+    /// uses the built in Windows MessageBox which may or may not
+    /// be sufficient for your needs. Using this class is easy
+    /// but feel free to develop your own IDialogService implementation
+    /// if needed.
+    /// </summary>
+    ////[ClassInfo(typeof(IDialogService))]
+    public class DialogService : IDialogService
+    {
+        /// <summary>
+        /// Displays information about an error.
+        /// </summary>
+        /// <param name="message">The message to be shown to the user.</param>
+        /// <param name="title">The title of the dialog box. This may be null.</param>
+        /// <param name="buttonText">The text shown in the only button
+        /// in the dialog box. If left null, the text "OK" will be used.</param>
+        /// <param name="afterHideCallback">A callback that should be executed after
+        /// the dialog box is closed by the user.</param>
+        /// <returns>A Task allowing this async method to be awaited.</returns>
+        /// <remarks>Displaying dialogs in Windows Phone is synchronous. As such,
+        /// this method will be executed synchronously even though it can be awaited
+        /// for cross-platform compatibility purposes.</remarks>
+        public Task ShowError(string message, string title, string buttonText, Action afterHideCallback)
+        {
+            var tcs = new TaskCompletionSource<bool>();
+            MessageBox.Show(message, title ?? string.Empty, MessageBoxButton.OK);
+
+            afterHideCallback?.Invoke();
+
+            tcs.SetResult(true);
+            return tcs.Task;
+        }
+
+        /// <summary>
+        /// Displays information about an error.
+        /// </summary>
+        /// <param name="error">The exception of which the message must be shown to the user.</param>
+        /// <param name="title">The title of the dialog box. This may be null.</param>
+        /// <param name="buttonText">The text shown in the only button
+        /// in the dialog box. If left null, the text "OK" will be used.</param>
+        /// <param name="afterHideCallback">A callback that should be executed after
+        /// the dialog box is closed by the user.</param>
+        /// <returns>A Task allowing this async method to be awaited.</returns>
+        /// <remarks>Displaying dialogs in Windows Phone is synchronous. As such,
+        /// this method will be executed synchronously even though it can be awaited
+        /// for cross-platform compatibility purposes.</remarks>
+        public Task ShowError(Exception error, string title, string buttonText, Action afterHideCallback)
+        {
+            var tcs = new TaskCompletionSource<bool>();
+            MessageBox.Show(error.Message, title ?? string.Empty, MessageBoxButton.OK);
+
+            afterHideCallback?.Invoke();
+
+            tcs.SetResult(true);
+            return tcs.Task;
+        }
+
+        /// <summary>
+        /// Displays information to the user. The dialog box will have only
+        /// one button with the text "OK".
+        /// </summary>
+        /// <param name="message">The message to be shown to the user.</param>
+        /// <param name="title">The title of the dialog box. This may be null.</param>
+        /// <returns>A Task allowing this async method to be awaited.</returns>
+        /// <remarks>Displaying dialogs in Windows Phone is synchronous. As such,
+        /// this method will be executed synchronously even though it can be awaited
+        /// for cross-platform compatibility purposes.</remarks>
+        public Task ShowMessage(string message, string title)
+        {
+            var tcs = new TaskCompletionSource<bool>();
+            ShowMessage(message, title ?? string.Empty, null, null);
+            tcs.SetResult(true);
+            return tcs.Task;
+        }
+
+        /// <summary>
+        /// Displays information to the user. The dialog box will have only
+        /// one button.
+        /// </summary>
+        /// <param name="message">The message to be shown to the user.</param>
+        /// <param name="title">The title of the dialog box. This may be null.</param>
+        /// <param name="buttonText">The text shown in the only button
+        /// in the dialog box. If left null, the text "OK" will be used.</param>
+        /// <param name="afterHideCallback">A callback that should be executed after
+        /// the dialog box is closed by the user.</param>
+        /// <returns>A Task allowing this async method to be awaited.</returns>
+        /// <remarks>Displaying dialogs in Windows Phone is synchronous. As such,
+        /// this method will be executed synchronously even though it can be awaited
+        /// for cross-platform compatibility purposes.</remarks>
+        public Task ShowMessage(string message, string title, string buttonText, Action afterHideCallback)
+        {
+            var tcs = new TaskCompletionSource<bool>();
+            MessageBox.Show(message, title ?? string.Empty, MessageBoxButton.OK);
+
+            afterHideCallback?.Invoke();
+
+            tcs.SetResult(true);
+            return tcs.Task;
+        }
+
+        /// <summary>
+        /// Displays information to the user. The dialog box will have only
+        /// one button.
+        /// </summary>
+        /// <param name="message">The message to be shown to the user.</param>
+        /// <param name="title">The title of the dialog box. This may be null.</param>
+        /// <param name="buttonConfirmText">The text shown in the "confirm" button
+        /// in the dialog box. If left null, the text "OK" will be used.</param>
+        /// <param name="buttonCancelText">The text shown in the "cancel" button
+        /// in the dialog box. If left null, the text "Cancel" will be used.</param>
+        /// <param name="afterHideCallback">A callback that should be executed after
+        /// the dialog box is closed by the user. The callback method will get a boolean
+        /// parameter indicating if the "confirm" button (true) or the "cancel" button
+        /// (false) was pressed by the user.</param>
+        /// <returns>A Task allowing this async method to be awaited. The task will return
+        /// true or false depending on the dialog result.</returns>
+        /// <remarks>Displaying dialogs in Windows Phone is synchronous. As such,
+        /// this method will be executed synchronously even though it can be awaited
+        /// for cross-platform compatibility purposes.</remarks>
+        public Task<bool> ShowMessage(
+            string message,
+            string title,
+            string buttonConfirmText,
+            string buttonCancelText,
+            Action<bool> afterHideCallback)
+        {
+            var tcs = new TaskCompletionSource<bool>();
+            var result = MessageBox.Show(message, title ?? string.Empty, MessageBoxButton.OKCancel);
+
+            afterHideCallback?.Invoke(result == MessageBoxResult.OK || result == MessageBoxResult.Yes);
+
+            tcs.SetResult(result == MessageBoxResult.OK || result == MessageBoxResult.Yes);
+            return tcs.Task;
+        }
+
+        /// <summary>
+        /// Displays information to the user in a simple dialog box. The dialog box will have only
+        /// one button with the text "OK". This method should be used for debugging purposes.
+        /// </summary>
+        /// <param name="message">The message to be shown to the user.</param>
+        /// <param name="title">The title of the dialog box. This may be null.</param>
+        /// <returns>A Task allowing this async method to be awaited.</returns>
+        /// <remarks>Displaying dialogs in Windows Phone is synchronous. As such,
+        /// this method will be executed synchronously even though it can be awaited
+        /// for cross-platform compatibility purposes.</remarks>
+        public Task ShowMessageBox(string message, string title)
+        {
+            var tcs = new TaskCompletionSource<bool>();
+            MessageBox.Show(message, title ?? string.Empty, MessageBoxButton.OK);
+            tcs.SetResult(true);
+            return Empty.Task;
+        }
+    }
+}