Add RenewContext

Elwig/Helpers/AppDbContext.cs

@@ -40,6 +40,9 @@ namespace Elwig.Helpers {
         public DbSet<DeliveryPartModifier> DeliveryPartModifiers { get; private set; }
 
         private readonly StreamWriter? LogFile = null;
+        public static DateTime LastWriteTime => File.GetLastWriteTime(App.Config.DatabaseFile);
+        public DateTime SavedLastWriteTime { get; private set; }
+        public bool HasBackendChanged => SavedLastWriteTime != LastWriteTime;
 
         public AppDbContext() {
             if (App.Config.DatabaseLog != null) {
@@ -52,6 +55,9 @@ namespace Elwig.Helpers {
                     MessageBox.Show($"Unable to open database log file:\n\n{e.Message}", "Database Log", MessageBoxButton.OK, MessageBoxImage.Error);
                 }
             }
+            SavedLastWriteTime = LastWriteTime;
+            SavedChanges += OnSavedChanges;
+
         }
 
         protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder) {
@@ -67,6 +73,10 @@ namespace Elwig.Helpers {
             GC.SuppressFinalize(this);
         }
 
+        private void OnSavedChanges(object? sender, SavedChangesEventArgs evt) {
+            SavedLastWriteTime = LastWriteTime;
+        }
+
         protected void Log(string msg) {
             LogFile?.WriteLine(msg);
         }

Elwig/Helpers/Utils.cs

@@ -10,6 +10,7 @@ using System.Windows.Controls.Primitives;
 using System.Text.RegularExpressions;
 using System.IO.Ports;
 using System.Net.Sockets;
+using System.Collections;
 
 namespace Elwig.Helpers {
     public static partial class Utils {
@@ -129,6 +130,40 @@ namespace Elwig.Helpers {
             return null;
         }
 
+        public static void RenewItemsSource(Selector selector, IEnumerable? source, Func<object?, object?> getId) {
+            var selectedId = getId(selector.SelectedItem);
+            selector.ItemsSource = source;
+            if (selectedId != null && source != null)
+                selector.SelectedItem = source.Cast<object>().FirstOrDefault(i => selectedId.Equals(getId(i)));
+        }
+
+        public static void RenewItemsSource(Xceed.Wpf.Toolkit.Primitives.Selector selector, IEnumerable? source, Func<object?, object?> getId) {
+            var selectedIds = selector.SelectedItems.Cast<object>().Select(i => getId(i)).ToList();
+            selector.ItemsSource = source;
+            if (source != null) {
+                foreach (var i in source.Cast<object>().Where(i => selectedIds.Contains(getId(i))))
+                    selector.SelectedItems.Add(i);
+            }
+        }
+
+        public static void RenewItemsSource(DataGrid dataGrid, IEnumerable? source, Func<object?, object?> getId, bool keepSort = true) {
+            var column = dataGrid.CurrentCell.Column;
+            var sortColumns = dataGrid.Columns.Select(c => c.SortDirection).ToList();
+            var sort = dataGrid.Items.SortDescriptions.ToList();
+            var selectedId = getId(dataGrid.SelectedItem);
+            dataGrid.ItemsSource = source;
+            if (keepSort) {
+                for (int i = 0; i < dataGrid.Columns.Count; i++)
+                    dataGrid.Columns[i].SortDirection = sortColumns[i];
+                foreach (var s in sort)
+                    dataGrid.Items.SortDescriptions.Add(s);
+            }
+            if (selectedId != null && source != null)
+                dataGrid.SelectedItem = source.Cast<object>().FirstOrDefault(i => selectedId.Equals(getId(i)));
+            if (dataGrid.SelectedItem != null)
+                dataGrid.CurrentCell = new(dataGrid.SelectedItem, column);
+        }
+
         public static int Modulo(string a, int b) {
             if (a.Length == 0 || !a.All(char.IsAsciiDigit)) {
                 throw new ArgumentException("First argument has to be a decimal string");

Elwig/Windows/AdministrationWindow.cs

@@ -1,27 +1,56 @@
 using Elwig.Helpers;
+using Elwig.Models;
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Threading.Tasks;
 using System.Windows;
 using System.Windows.Controls;
+using Xceed.Wpf.Toolkit;
 
 namespace Elwig.Windows {
     public abstract class AdministrationWindow : ContextWindow {
 
         protected Control[] ExemptInputs { private get; set; }
         protected Control[] RequiredInputs { private get; set; }
+
+        private bool _IsEditing;
+        private bool _IsCreating;
+        protected bool IsEditing {
+            get { return _IsEditing; }
+            set {
+                _IsEditing = value;
+                LockContext = IsEditing || IsCreating;
+            }
+        }
+        protected bool IsCreating {
+            get { return _IsCreating; }
+            set {
+                _IsCreating = value;
+                LockContext = IsEditing || IsCreating;
+            }
+        }
+
         private TextBox[] TextBoxInputs;
+        private TextBox[] PlzInputs;
         private ComboBox[] ComboBoxInputs;
+        private ComboBox[] PlzOrtInputs;
+        private CheckComboBox[] CheckComboBoxInputs;
         private CheckBox[] CheckBoxInputs;
         private RadioButton[] RadioButtonInputs;
         private readonly Dictionary<Control, bool> Valid;
         private readonly Dictionary<Control, object?> OriginalValues;
 
         public AdministrationWindow() : base() {
+            IsEditing = false;
+            IsCreating = false;
             ExemptInputs = Array.Empty<Control>();
             RequiredInputs = Array.Empty<Control>();
             TextBoxInputs = Array.Empty<TextBox>();
+            PlzInputs = Array.Empty<TextBox>();
             ComboBoxInputs = Array.Empty<ComboBox>();
+            CheckComboBoxInputs = Array.Empty<CheckComboBox>();
+            PlzOrtInputs = Array.Empty<ComboBox>();
             CheckBoxInputs = Array.Empty<CheckBox>();
             RadioButtonInputs = Array.Empty<RadioButton>();
             Valid = new();
@@ -33,14 +62,30 @@ namespace Elwig.Windows {
             TextBoxInputs = Utils.FindAllChildren<TextBox>(this, ExemptInputs).ToArray();
             ComboBoxInputs = Utils.FindAllChildren<ComboBox>(this, ExemptInputs).ToArray();
             CheckBoxInputs = Utils.FindAllChildren<CheckBox>(this, ExemptInputs).ToArray();
+            CheckComboBoxInputs = Utils.FindAllChildren<CheckComboBox>(this, ExemptInputs).ToArray();
             RadioButtonInputs = Utils.FindAllChildren<RadioButton>(this, ExemptInputs).ToArray();
+            PlzInputs = TextBoxInputs.Where(tb => "PLZ".Equals(tb.Tag)).ToArray();
+            PlzOrtInputs = PlzInputs.Select(tb => Utils.FindNextSibling<ComboBox>(tb) ?? throw new MissingMemberException()).ToArray();
             foreach (var tb in TextBoxInputs)
                 Valid[tb] = true;
+            foreach (var cb in ComboBoxInputs)
+                cb.SelectionChanged += ComboBox_SelectionChanged;
+            foreach (var cb in CheckComboBoxInputs)
+                cb.ItemSelectionChanged += ComboBox_SelectionChanged;
             ValidateRequiredInputs();
         }
 
+        private ComboBox GetPlzOrtInput(TextBox input) {
+            return PlzOrtInputs[Array.IndexOf(PlzInputs, input)];
+        }
+
         abstract protected void UpdateButtons();
 
+        protected override async Task RenewContext() {
+            for (int i = 0; i < PlzInputs.Length; i++)
+                UpdatePlz(PlzInputs[i], PlzOrtInputs[i]);
+        }
+
         protected void ValidateInput(Control input, bool valid) {
             Valid[input] = valid;
         }
@@ -122,6 +167,10 @@ namespace Elwig.Windows {
 
         protected bool IsValid => Valid.All(kv => kv.Value);
 
+        protected bool GetInputValid(Control input) {
+            return Valid[input];
+        }
+
         protected bool InputHasChanged(Control input) {
             if (!OriginalValues.ContainsKey(input)) {
                 return false;
@@ -145,14 +194,13 @@ namespace Elwig.Windows {
             CheckBoxInputs.Any(InputHasChanged) ||
             RadioButtonInputs.Any(InputHasChanged);
 
-        protected void UpdatePlz(TextBox plzInput, bool plzInputValid, ComboBox ortInput) {
+        protected void UpdatePlz(TextBox plzInput, ComboBox ortInput) {
+            var plzInputValid = GetInputValid(plzInput);
             var item = ortInput.SelectedItem;
             var list = plzInputValid && plzInput.Text.Length == 4 ? Context.Postleitzahlen.Find(int.Parse(plzInput.Text))?.Orte.ToList() : null;
-            ortInput.ItemsSource = list;
+            Utils.RenewItemsSource(ortInput, list, i => (i as AT_PlzDest)?.Id);
-            ortInput.SelectedItem = (list != null && item != null && list.Contains(item)) ? item : null;
             if (list != null && ortInput.SelectedItem == null && list.Count == 1)
                 ortInput.SelectedItem = list[0];
-            ComboBox_SelectionChanged(ortInput, new());
         }
 
         protected bool InputTextChanged(TextBox input, Func<TextBox, bool, ValidationResult> checker) {
@@ -188,7 +236,7 @@ namespace Elwig.Windows {
 
         protected bool InputLostFocus(TextBox input, ValidationResult res, string? msg = null) {
             if (!res.IsValid)
-                MessageBox.Show(res.ErrorContent.ToString(), msg ?? res.ErrorContent.ToString(), MessageBoxButton.OK, MessageBoxImage.Warning);
+                System.Windows.MessageBox.Show(res.ErrorContent.ToString(), msg ?? res.ErrorContent.ToString(), MessageBoxButton.OK, MessageBoxImage.Warning);
             return res.IsValid;
         }
 
@@ -270,14 +318,14 @@ namespace Elwig.Windows {
 
         protected void PlzInput_TextChanged(object sender, RoutedEventArgs evt) {
             var plz = (TextBox)sender;
-            var valid = InputTextChanged(plz, Validator.CheckPlz);
+            InputTextChanged(plz, Validator.CheckPlz);
-            UpdatePlz(plz, valid, Utils.FindNextSibling<ComboBox>(plz));
+            UpdatePlz(plz, GetPlzOrtInput(plz));
         }
 
         protected void PlzInput_LostFocus(object sender, RoutedEventArgs evt) {
             var plz = (TextBox)sender;
-            var valid = InputLostFocus(plz, Validator.CheckPlz);
+            InputLostFocus(plz, Validator.CheckPlz);
-            UpdatePlz(plz, valid, Utils.FindNextSibling<ComboBox>(plz));
+            UpdatePlz(plz, GetPlzOrtInput(plz));
         }
 
         protected void EmailInput_TextChanged(object sender, RoutedEventArgs evt) {

Elwig/Windows/AreaComAdminWindow.xaml.cs

@@ -39,6 +39,10 @@ namespace Elwig.Windows {
             CultInput.ItemsSource = Context.WineCultivations.OrderBy(c => c.Name).ToList();
         }
 
+        protected override async Task RenewContext() {
+            await base.RenewContext();
+        }
+
         private async Task RefreshContractList() {
             /*
             await Context.Contracts.LoadAsync();

Elwig/Windows/ClientParamWindow.xaml.cs

@@ -1,4 +1,6 @@
 
+using System.Threading.Tasks;
+
 namespace Elwig.Windows {
     public partial class ClientParamWindow : AdministrationWindow {
         public ClientParamWindow() {
@@ -8,5 +10,9 @@ namespace Elwig.Windows {
         protected override void UpdateButtons() {
 
         }
+
+        protected override async Task RenewContext() {
+
+        }
     }
 }

Elwig/Windows/ContextWindow.cs

@@ -1,19 +1,43 @@
 using Elwig.Helpers;
 using System;
+using System.Threading.Tasks;
 using System.Windows;
+using System.Windows.Threading;
 
 namespace Elwig.Windows {
     public abstract class ContextWindow : Window {
 
-        protected readonly AppDbContext Context;
+        protected AppDbContext Context { get; private set; }
+        protected bool LockContext { get; set; } = false;
+
+        private readonly DispatcherTimer ContextRenewTimer;
+        private static readonly int ContextRenewSec = 10;
 
         public ContextWindow() : base() {
+            ContextRenewTimer = new DispatcherTimer();
+            ContextRenewTimer.Tick += new EventHandler(OnRenewContext);
+            ContextRenewTimer.Interval = new TimeSpan(0, 0, ContextRenewSec);
+            ContextRenewTimer.Start();
             Context = new();
+            Loaded += OnLoaded;
+        }
+
+        private void OnRenewContext(object? sender, EventArgs evt) {
+            if (LockContext || !Context.HasBackendChanged) return;
+            Context.Dispose();
+            Context = new();
+            RenewContext();
+        }
+
+        private void OnLoaded(object sender, RoutedEventArgs evt) {
+            RenewContext();
         }
 
         protected override void OnClosed(EventArgs evt) {
             base.OnClosed(evt);
             Context.Dispose();
         }
+
+        abstract protected Task RenewContext();
     }
 }

Elwig/Windows/DeliveryAdminWindow.xaml.cs

@@ -1,8 +1,10 @@
 using Elwig.Helpers;
 using Elwig.Models;
+using Microsoft.EntityFrameworkCore;
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Threading.Tasks;
 using System.Windows;
 using System.Windows.Controls;
 using System.Windows.Threading;
@@ -25,7 +27,6 @@ namespace Elwig.Windows {
                 WineOriginInput, WineKgInput
             };
             ExemptInputs = new Control[] {
-                MgNrInput, MemberInput,
                 LsNrInput, DateInput, TimeInput, BranchInput,
                 MemberAddressField
             };
@@ -37,15 +38,7 @@ namespace Elwig.Windows {
         }
 
         private void Window_Loaded(object sender, RoutedEventArgs evt) {
-            MemberInput.ItemsSource = Context.Members.OrderBy(m => m.FamilyName).ThenBy(m => m.GivenName).ToList();
+
-            BranchInput.ItemsSource = Context.Branches.OrderBy(b => b.Name).ToList();
-            BranchInput.SelectedItem = BranchInput.ItemsSource.Cast<Branch>().First(b => b.ZwstId == App.ZwstId);
-            WineVarietyInput.ItemsSource = Context.WineVarieties.OrderBy(v => v.Name).ToList();
-            AttributesInput.ItemsSource = Context.WineAttributes.OrderBy(a => a.Name).ToList();
-            WineQualityLevelInput.ItemsSource = Context.WineQualityLevels.ToList();
-            ModifiersInput.ItemsSource = Context.Modifiers.Where(m => m.Season.Year == 2022).OrderBy(m => m.Name).ToList();
-            WineOriginInput.ItemsSource = Context.WineOrigins.ToList().OrderByDescending(o => o.SortKey).ThenBy(o => o.HkId);
-            WineKgInput.ItemsSource = Context.WbKgs.Select(k => k.AtKg).OrderBy(k => k.Name).ToList();
         }
 
         private void OnSecondPassed(object? sender, EventArgs evt) {
@@ -58,6 +51,21 @@ namespace Elwig.Windows {
 
         }
 
+        protected override async Task RenewContext() {
+            await base.RenewContext();
+            Utils.RenewItemsSource(MemberInput, await Context.Members.OrderBy(m => m.FamilyName).ThenBy(m => m.GivenName).ToListAsync(), i => (i as Member)?.MgNr);
+            Utils.RenewItemsSource(BranchInput, await Context.Branches.OrderBy(b => b.Name).ToListAsync(), i => (i as Branch)?.ZwstId);
+            BranchInput.SelectedItem = BranchInput.ItemsSource.Cast<Branch>().First(b => b.ZwstId == App.ZwstId);
+            Utils.RenewItemsSource(WineVarietyInput, await Context.WineVarieties.OrderBy(v => v.Name).ToListAsync(), i => (i as WineVar)?.SortId);
+            Utils.RenewItemsSource(AttributesInput, await Context.WineAttributes.OrderBy(a => a.Name).ToListAsync(), i => (i as WineAttr)?.AttrId);
+            Utils.RenewItemsSource(WineQualityLevelInput, await Context.WineQualityLevels.ToListAsync(), i => (i as WineQualLevel)?.QualId);
+            Utils.RenewItemsSource(ModifiersInput, await Context.Modifiers.Where(m => m.Season.Year == 2022).OrderBy(m => m.Name).ToListAsync(), i => (i as Modifier)?.ModId);
+            Utils.RenewItemsSource(WineOriginInput, (await Context.WineOrigins.ToListAsync()).OrderByDescending(o => o.SortKey).ThenBy(o => o.HkId), i => (i as WineOrigin)?.HkId);
+            Utils.RenewItemsSource(WineKgInput, await Context.WbKgs.Select(k => k.AtKg).OrderBy(k => k.Name).ToListAsync(), i => (i as AT_Kg)?.KgNr);
+            UpdateWineQualityLevels();
+            UpdateRdInput();
+        }
+
         private void MgNrInput_TextChanged(object sender, TextChangedEventArgs evt) {
             var valid = InputTextChanged((TextBox)sender, Validator.CheckMgNr);
             MemberInput.SelectedItem = valid ? Context.Members.Find(int.Parse(MgNrInput.Text)) : null;
@@ -177,17 +185,20 @@ namespace Elwig.Windows {
             UpdateWineOrigin();
         }
 
-        private void WineKgInput_SelectionChanged(object sender, SelectionChangedEventArgs evt) {
+        private void UpdateRdInput() {
-            UpdateWineOrigin();
+            if (WineKgInput.SelectedItem is AT_Kg kg) {
-            var kg = (AT_Kg)WineKgInput.SelectedItem;
-            if (kg != null) {
                 var list = Context.WbRde.Where(r => r.KgNr == kg.KgNr).OrderBy(r => r.Name).Cast<object>().ToList();
                 list.Insert(0, new NullItem());
-                WineRdInput.ItemsSource = list;
+                Utils.RenewItemsSource(WineRdInput, list, i => ((i as WbRd)?.KgNr, (i as WbRd)?.RdNr));
-                WineRdInput.SelectedIndex = 0;
+                if (WineRdInput.SelectedItem == null) WineRdInput.SelectedIndex = 0;
             } else {
                 WineRdInput.ItemsSource = null;
             }
         }
+
+        private void WineKgInput_SelectionChanged(object sender, SelectionChangedEventArgs evt) {
+            UpdateWineOrigin();
+            UpdateRdInput();
+        }
     }
 }

Elwig/Windows/MemberAdminWindow.xaml

@@ -152,9 +152,8 @@
 
                 <Label Content="PLZ/Ort:" Margin="10,160,0,0" Grid.Column="0"/>
                 <TextBox x:Name="PlzInput" Margin="0,160,0,0" Width="42" Grid.Column="1" HorizontalAlignment="Left"
-                         TextChanged="PlzInput_TextChanged" LostFocus="PlzInput_LostFocus"/>
+                         TextChanged="PlzInput_TextChanged" LostFocus="PlzInput_LostFocus" Tag="PLZ"/>
                 <ComboBox x:Name="OrtInput" ItemTemplate="{StaticResource PostalDestTemplate}" TextSearch.TextPath="Ort.Name"
-                          SelectionChanged="ComboBox_SelectionChanged"
                           Margin="47,160,10,0" Grid.Column="1" Grid.ColumnSpan="3"/>
             </Grid>
         </GroupBox>
@@ -240,9 +239,8 @@
 
                 <Label Content="PLZ/Ort:" Margin="10,70,0,0" Grid.Column="0"/>
                 <TextBox x:Name="BillingPlzInput" Margin="0,70,0,0" Width="42" Grid.Column="1" HorizontalAlignment="Left"
-                         TextChanged="PlzInput_TextChanged" LostFocus="PlzInput_LostFocus"/>
+                         TextChanged="PlzInput_TextChanged" LostFocus="PlzInput_LostFocus" Tag="PLZ"/>
                 <ComboBox x:Name="BillingOrtInput" ItemTemplate="{StaticResource PostalDestTemplate}" TextSearch.TextPath="Ort.Name"
-                          SelectionChanged="ComboBox_SelectionChanged"
                           Margin="47,70,10,0" Grid.Column="1"/>
             </Grid>
         </GroupBox>
@@ -284,12 +282,10 @@
 
                 <Label Content="StammZwst.:" Margin="10,130,0,0" Grid.Column="0"/>
                 <ComboBox x:Name="BranchInput" DisplayMemberPath="Name" TextSearch.TextPath="Name"
-                          SelectionChanged="ComboBox_SelectionChanged"
                           Margin="0,130,10,0" Grid.Column="1" Grid.ColumnSpan="2"/>
 
                 <Label Content="Stammgemeinde:" Margin="10,160,0,0" Grid.Column="0"/>
                 <ComboBox x:Name="DefaultKgInput" DisplayMemberPath="Name" TextSearch.TextPath="Name"
-                          SelectionChanged="ComboBox_SelectionChanged"
                           Margin="0,160,10,0" Grid.Column="1" Grid.ColumnSpan="2"/>
 
                 <Label Content="Anmerkung:" Margin="10,190,0,0" Grid.Column="0"/>

Elwig/Windows/MemberAdminWindow.xaml.cs

@@ -12,8 +12,7 @@ using Microsoft.EntityFrameworkCore.ChangeTracking;
 
 namespace Elwig.Windows {
     public partial class MemberAdminWindow : AdministrationWindow {
-        private bool IsEditing = false;
+
-        private bool IsCreating = false;
         private List<string> TextFilter = new();
         private readonly RoutedCommand CtrlF = new();
 
@@ -35,8 +34,6 @@ namespace Elwig.Windows {
 
         private void Window_Loaded(object sender, RoutedEventArgs evt) {
             ActiveMemberInput.IsChecked = true;
-            BranchInput.ItemsSource = Context.Branches.OrderBy(b => b.Name).ToList();
-            DefaultKgInput.ItemsSource = Context.WbKgs.Select(k => k.AtKg).OrderBy(k => k.Name).ToList();
         }
 
         private async Task RefreshMemberList() {
@@ -44,7 +41,7 @@ namespace Elwig.Windows {
             await RefreshMemberListQuery();
         }
 
-        private async Task RefreshMemberListQuery() {
+        private async Task RefreshMemberListQuery(bool updateSort = false) {
             IQueryable<Member> memberQuery = Context.Members;
             if (ActiveMemberInput.IsChecked == true)
                 memberQuery = memberQuery.Where(m => m.IsActive);
@@ -67,7 +64,7 @@ namespace Elwig.Windows {
                     .ToList();
             }
 
-            MemberList.ItemsSource = members;
+            Utils.RenewItemsSource(MemberList, members, i => (i as Member)?.MgNr, !updateSort);
             if (members.Count == 1)
                 MemberList.SelectedIndex = 0;
 
@@ -104,6 +101,13 @@ namespace Elwig.Windows {
             ValidateRequiredInputs();
         }
 
+        protected override async Task RenewContext() {
+            await base.RenewContext();
+            Utils.RenewItemsSource(BranchInput, await Context.Branches.OrderBy(b => b.Name).ToListAsync(), i => (i as Branch)?.ZwstId);
+            Utils.RenewItemsSource(DefaultKgInput, await Context.WbKgs.Select(k => k.AtKg).OrderBy(k => k.Name).ToListAsync(), i => (i as AT_Kg)?.KgNr);
+            await RefreshMemberList();
+        }
+
         private void MemberList_SelectionChanged(object sender, RoutedEventArgs evt) {
             RefreshInputs();
         }
@@ -195,7 +199,7 @@ namespace Elwig.Windows {
 
         private async void SearchInput_TextChanged(object sender, RoutedEventArgs evt) {
             TextFilter = SearchInput.Text.ToLower().Split(" ").ToList().FindAll(e => e.Length > 0);
-            await RefreshMemberListQuery();
+            await RefreshMemberListQuery(true);
         }
 
         private void Menu_Member_SendEmail_Click(object sender, RoutedEventArgs evt) {
@@ -358,11 +362,9 @@ namespace Elwig.Windows {
             AT_PlzDest? p = m.PostalDest.AtPlz;
             if (p != null) {
                 PlzInput.Text = p.Plz.ToString();
-                OrtInput.ItemsSource = p.AtPlz.Orte;
                 OrtInput.SelectedItem = p;
             } else {
                 PlzInput.Text = null;
-                OrtInput.ItemsSource = null;
                 OrtInput.SelectedItem = null;
             }
 
@@ -385,14 +387,12 @@ namespace Elwig.Windows {
                 AT_PlzDest? b = billingAddr.PostalDest.AtPlz;
                 if (b != null) {
                     BillingPlzInput.Text = b.Plz.ToString();
-                    BillingOrtInput.ItemsSource = b.AtPlz.Orte;
                     BillingOrtInput.SelectedItem = b;
                 }
             } else {
                 BillingNameInput.Text = "";
                 BillingAddressInput.Text = "";
                 BillingPlzInput.Text = "";
-                BillingOrtInput.ItemsSource = null;
                 BillingOrtInput.SelectedItem = null;
             }