Ground work for Wino Calendar. (#475)

Wino Calendar abstractions.

Wino.Core.UWP/Selectors/CustomWinoMessageDialogIconSelector.cs

@@ -0,0 +1,38 @@
+using System;
+using Windows.UI.Xaml;
+using Windows.UI.Xaml.Controls;
+using Wino.Core.Domain.Enums;
+
+namespace Wino.Core.UWP.Selectors
+{
+    public class CustomWinoMessageDialogIconSelector : DataTemplateSelector
+    {
+        public DataTemplate InfoIconTemplate { get; set; }
+        public DataTemplate WarningIconTemplate { get; set; }
+        public DataTemplate QuestionIconTemplate { get; set; }
+        public DataTemplate ErrorIconTemplate { get; set; }
+
+        protected override DataTemplate SelectTemplateCore(object item, DependencyObject container)
+        {
+            if (item == null) return null;
+
+            if (item is WinoCustomMessageDialogIcon icon)
+            {
+                switch (icon)
+                {
+                    case WinoCustomMessageDialogIcon.Information:
+                        return InfoIconTemplate;
+                    case WinoCustomMessageDialogIcon.Warning:
+                        return WarningIconTemplate;
+                    case WinoCustomMessageDialogIcon.Error:
+                        return ErrorIconTemplate;
+                    case WinoCustomMessageDialogIcon.Question:
+                        return QuestionIconTemplate;
+                    default:
+                        throw new Exception("Unknown custom message dialog icon.");
+                }
+            }
+            return base.SelectTemplateCore(item, container);
+        }
+    }
+}