Ground work for Wino Calendar. (#475)

Wino Calendar abstractions.

Wino.Core.UWP/Dialogs/AccountPickerDialog.xaml.cs

@@ -0,0 +1,27 @@
+using System.Collections.Generic;
+using Windows.UI.Xaml.Controls;
+using Wino.Core.Domain.Entities.Shared;
+
+namespace Wino.Dialogs
+{
+    public sealed partial class AccountPickerDialog : ContentDialog
+    {
+        public MailAccount PickedAccount { get; set; }
+
+        public List<MailAccount> AvailableAccounts { get; set; }
+
+        public AccountPickerDialog(List<MailAccount> availableAccounts)
+        {
+            AvailableAccounts = availableAccounts;
+
+            InitializeComponent();
+        }
+
+        private void AccountClicked(object sender, ItemClickEventArgs e)
+        {
+            PickedAccount = e.ClickedItem as MailAccount;
+
+            Hide();
+        }
+    }
+}