diff --git a/demo/Ursa.Demo/Pages/DialogDemo.axaml b/demo/Ursa.Demo/Pages/DialogDemo.axaml
index 7fce698..c51bbb4 100644
--- a/demo/Ursa.Demo/Pages/DialogDemo.axaml
+++ b/demo/Ursa.Demo/Pages/DialogDemo.axaml
@@ -12,193 +12,195 @@
     x:DataType="vm:DialogDemoViewModel"
     mc:Ignorable="d">
     <Grid ColumnDefinitions="Auto, *">
-        <TabControl Grid.Column="0" TabStripPlacement="Left">
-            <TabItem Header="Default Window Dialog">
-                <u:Form
-                    Width="300"
-                    Margin="16,0"
-                    DataContext="{Binding DefaultWindowDialogDemoViewModel}"
-                    LabelPosition="Top">
-                    <TextBox
-                        HorizontalAlignment="Stretch"
-                        u:FormItem.Label="Title"
-                        Text="{Binding Title}" />
-                    <u:EnumSelector
-                        HorizontalAlignment="Stretch"
-                        u:FormItem.Label="Startup Location"
-                        EnumType="WindowStartupLocation"
-                        Value="{Binding Location}" />
-                    <u:FormItem Label="PixelPosition">
-                        <UniformGrid Columns="2" Rows="1">
-                            <u:NumericIntUpDown InnerLeftContent="X" Value="{Binding X}" />
-                            <u:NumericIntUpDown InnerLeftContent="Y" Value="{Binding Y}" />
-                        </UniformGrid>
-                    </u:FormItem>
-                    <u:EnumSelector
-                        HorizontalAlignment="Stretch"
-                        u:FormItem.Label="Dialog Mode"
-                        EnumType="u:DialogMode"
-                        Value="{Binding Mode}" />
-                    <u:EnumSelector
-                        HorizontalAlignment="Stretch"
-                        u:FormItem.Label="Dialog Buttons"
-                        EnumType="u:DialogButton"
-                        Value="{Binding Button}" />
-                    <CheckBox u:FormItem.Label="Show In Taskbar" IsChecked="{Binding ShowInTaskBar}" />
-                    <CheckBox
-                        u:FormItem.Label="Is Close Button Visible"
-                        IsChecked="{Binding IsCloseButtonVisible}"
-                        IsThreeState="True" />
-                    <CheckBox u:FormItem.Label="CanDragMove" IsChecked="{Binding CanDragMove}" />
-                    <CheckBox u:FormItem.Label="CanResize" IsChecked="{Binding CanResize}" />
-                    <u:FormItem>
-                        <u:FormItem.Label>
-                            <StackPanel Orientation="Horizontal">
-                                <TextBlock Text="Style Class" />
-                                <PathIcon
-                                    Theme="{StaticResource InnerPathIcon}"
-                                    VerticalAlignment="Center"
-                                    TextElement.FontWeight="Normal"
-                                    Data="{DynamicResource SemiIconHelpCircle}"
-                                    ToolTip.Tip="Pass a Style Class to the created Dialog. In this example, if you set StyleClass as 'Custom', You will get Special Style for OK Button. These styles usually are defined in the root of your App/Window" />
-                            </StackPanel>
-                        </u:FormItem.Label>
-                        <TextBox HorizontalAlignment="Stretch" Text="{Binding StyleClass}" />
-                    </u:FormItem>
-                    <Button
-                        HorizontalAlignment="Left"
-                        u:FormItem.NoLabel="True"
-                        Command="{Binding ShowDialogCommand}"
-                        Content="Show" />
-                </u:Form>
-            </TabItem>
-            <TabItem Header="Custom Window Dialog">
-                <u:Form
-                    Width="300"
-                    Margin="16,0"
-                    DataContext="{Binding CustomWindowDialogDemoViewModel}"
-                    LabelPosition="Top">
-                    <TextBox
-                        HorizontalAlignment="Stretch"
-                        u:FormItem.Label="Title"
-                        Text="{Binding Title}" />
-                    <u:EnumSelector
-                        HorizontalAlignment="Stretch"
-                        u:FormItem.Label="Startup Location"
-                        EnumType="WindowStartupLocation"
-                        Value="{Binding Location}" />
-                    <u:FormItem Label="PixelPosition">
-                        <UniformGrid Columns="2" Rows="1">
-                            <u:NumericIntUpDown InnerLeftContent="X" Value="{Binding X}" />
-                            <u:NumericIntUpDown InnerLeftContent="Y" Value="{Binding Y}" />
-                        </UniformGrid>
-                    </u:FormItem>
-                    <CheckBox u:FormItem.Label="Show In Taskbar" IsChecked="{Binding ShowInTaskBar}" />
-                    <CheckBox
-                        u:FormItem.Label="Is Close Button Visible"
-                        IsChecked="{Binding IsCloseButtonVisible}"
-                        IsThreeState="True" />
-                    <CheckBox u:FormItem.Label="Modal" IsChecked="{Binding IsModal}" />
-                    <CheckBox u:FormItem.Label="CanDragMove" IsChecked="{Binding CanDragMove}" />
-                    <CheckBox u:FormItem.Label="CanResize" IsChecked="{Binding CanResize}" />
-                    <Button
-                        HorizontalAlignment="Left"
-                        u:FormItem.NoLabel="True"
-                        Command="{Binding ShowDialogCommand}"
-                        Content="Show" />
-                </u:Form>
-            </TabItem>
-            <TabItem Header="Default Overlay Dialog">
-                <u:Form
-                    Width="300"
-                    Margin="16,0"
-                    DataContext="{Binding DefaultOverlayDialogDemoViewModel}"
-                    LabelPosition="Top">
-                    <TextBox
-                        HorizontalAlignment="Stretch"
-                        u:FormItem.Label="Title"
-                        Text="{Binding Title}" />
-                    <u:EnumSelector
-                        HorizontalAlignment="Stretch"
-                        u:FormItem.Label="Dialog Mode"
-                        EnumType="u:DialogMode"
-                        Value="{Binding Mode}" />
-                    <u:EnumSelector
-                        HorizontalAlignment="Stretch"
-                        u:FormItem.Label="Dialog Buttons"
-                        EnumType="u:DialogButton"
-                        Value="{Binding Button}" />
-                    <CheckBox
-                        u:FormItem.Label="Is Close Button Visible"
-                        IsChecked="{Binding IsCloseButtonVisible}"
-                        IsThreeState="True" />
-                    <CheckBox u:FormItem.Label="Modal" IsChecked="{Binding IsModal}" />
-                    <CheckBox u:FormItem.Label="Can DragMove" IsChecked="{Binding CanDragMove}" />
-                    <CheckBox u:FormItem.Label="Can LightDismiss" IsChecked="{Binding CanLightDismiss}" />
-                    <CheckBox u:FormItem.Label="FullScreen" IsChecked="{Binding FullScreen}" />
-                    <CheckBox u:FormItem.Label="CanResize" IsChecked="{Binding CanResize}" />
-                    <ToggleSwitch
-                        u:FormItem.Label="Global/Local OverlayHost"
-                        IsChecked="{Binding IsLocal}"
-                        OffContent="Global"
-                        OnContent="Local" />
-                    <u:FormItem>
-                        <u:FormItem.Label>
-                            <StackPanel Orientation="Horizontal">
-                                <TextBlock Text="Style Class" />
-                                <PathIcon
-                                    Theme="{StaticResource InnerPathIcon}"
-                                    VerticalAlignment="Center"
-                                    TextElement.FontWeight="Normal"
-                                    Data="{DynamicResource SemiIconHelpCircle}"
-                                    ToolTip.Tip="Pass a Style Class to the created Dialog. In this example, if you set StyleClass as 'Custom', You will get Special Style for OK Button. These styles usually are defined in the root of your App/Window" />
-                            </StackPanel>
-                        </u:FormItem.Label>
-                        <TextBox HorizontalAlignment="Stretch" Text="{Binding StyleClass}" />
-                    </u:FormItem>
-                    <Button
-                        HorizontalAlignment="Left"
-                        u:FormItem.NoLabel="True"
-                        Command="{Binding ShowDialogCommand}"
-                        Content="Show" />
-                </u:Form>
-            </TabItem>
-            <TabItem Header="Custom Overlay Dialog">
-                <u:Form
-                    Width="300"
-                    Margin="16,0"
-                    DataContext="{Binding CustomOverlayDialogDemoViewModel}"
-                    LabelPosition="Top">
-                    <TextBox
-                        HorizontalAlignment="Stretch"
-                        u:FormItem.Label="Title"
-                        Text="{Binding Title}" />
-                    <CheckBox
-                        u:FormItem.Label="Is Close Button Visible"
-                        IsChecked="{Binding IsCloseButtonVisible}"
-                        IsThreeState="True" />
-                    <CheckBox u:FormItem.Label="Modal" IsChecked="{Binding IsModal}" />
-                    <CheckBox u:FormItem.Label="Can DragMove" IsChecked="{Binding CanDragMove}" />
-                    <CheckBox u:FormItem.Label="Can LightDismiss" IsChecked="{Binding CanLightDismiss}" />
-                    <CheckBox u:FormItem.Label="FullScreen" IsChecked="{Binding FullScreen}" />
-                    <CheckBox u:FormItem.Label="CanResize" IsChecked="{Binding CanResize}" />
-                    <ToggleSwitch
-                        u:FormItem.Label="Global/Local OverlayHost"
-                        IsChecked="{Binding IsLocal}"
-                        OffContent="Global"
-                        OnContent="Local" />
-                    <Button
-                        HorizontalAlignment="Left"
-                        u:FormItem.NoLabel="True"
-                        Command="{Binding ShowDialogCommand}"
-                        Content="Show" />
-                </u:Form>
-            </TabItem>
-        </TabControl>
+        <ScrollViewer>
+            <TabControl Grid.Column="0" TabStripPlacement="Left">
+                <TabItem Header="Default Window Dialog">
+                    <u:Form
+                        Width="300"
+                        Margin="16,0"
+                        DataContext="{Binding DefaultWindowDialogDemoViewModel}"
+                        LabelPosition="Top">
+                        <TextBox
+                            HorizontalAlignment="Stretch"
+                            u:FormItem.Label="Title"
+                            Text="{Binding Title}" />
+                        <u:EnumSelector
+                            HorizontalAlignment="Stretch"
+                            u:FormItem.Label="Startup Location"
+                            EnumType="WindowStartupLocation"
+                            Value="{Binding Location}" />
+                        <u:FormItem Label="PixelPosition">
+                            <UniformGrid Columns="2" Rows="1">
+                                <u:NumericIntUpDown InnerLeftContent="X" Value="{Binding X}" />
+                                <u:NumericIntUpDown InnerLeftContent="Y" Value="{Binding Y}" />
+                            </UniformGrid>
+                        </u:FormItem>
+                        <u:EnumSelector
+                            HorizontalAlignment="Stretch"
+                            u:FormItem.Label="Dialog Mode"
+                            EnumType="u:DialogMode"
+                            Value="{Binding Mode}" />
+                        <u:EnumSelector
+                            HorizontalAlignment="Stretch"
+                            u:FormItem.Label="Dialog Buttons"
+                            EnumType="u:DialogButton"
+                            Value="{Binding Button}" />
+                        <CheckBox u:FormItem.Label="Show In Taskbar" IsChecked="{Binding ShowInTaskBar}" />
+                        <CheckBox
+                            u:FormItem.Label="Is Close Button Visible"
+                            IsChecked="{Binding IsCloseButtonVisible}"
+                            IsThreeState="True" />
+                        <CheckBox u:FormItem.Label="CanDragMove" IsChecked="{Binding CanDragMove}" />
+                        <CheckBox u:FormItem.Label="CanResize" IsChecked="{Binding CanResize}" />
+                        <u:FormItem>
+                            <u:FormItem.Label>
+                                <StackPanel Orientation="Horizontal">
+                                    <TextBlock Text="Style Class" />
+                                    <PathIcon
+                                        VerticalAlignment="Center"
+                                        Data="{DynamicResource SemiIconHelpCircle}"
+                                        TextElement.FontWeight="Normal"
+                                        Theme="{StaticResource InnerPathIcon}"
+                                        ToolTip.Tip="Pass a Style Class to the created Dialog. In this example, if you set StyleClass as 'Custom', You will get Special Style for OK Button. These styles usually are defined in the root of your App/Window" />
+                                </StackPanel>
+                            </u:FormItem.Label>
+                            <TextBox HorizontalAlignment="Stretch" Text="{Binding StyleClass}" />
+                        </u:FormItem>
+                        <Button
+                            HorizontalAlignment="Left"
+                            u:FormItem.NoLabel="True"
+                            Command="{Binding ShowDialogCommand}"
+                            Content="Show" />
+                    </u:Form>
+                </TabItem>
+                <TabItem Header="Custom Window Dialog">
+                    <u:Form
+                        Width="300"
+                        Margin="16,0"
+                        DataContext="{Binding CustomWindowDialogDemoViewModel}"
+                        LabelPosition="Top">
+                        <TextBox
+                            HorizontalAlignment="Stretch"
+                            u:FormItem.Label="Title"
+                            Text="{Binding Title}" />
+                        <u:EnumSelector
+                            HorizontalAlignment="Stretch"
+                            u:FormItem.Label="Startup Location"
+                            EnumType="WindowStartupLocation"
+                            Value="{Binding Location}" />
+                        <u:FormItem Label="PixelPosition">
+                            <UniformGrid Columns="2" Rows="1">
+                                <u:NumericIntUpDown InnerLeftContent="X" Value="{Binding X}" />
+                                <u:NumericIntUpDown InnerLeftContent="Y" Value="{Binding Y}" />
+                            </UniformGrid>
+                        </u:FormItem>
+                        <CheckBox u:FormItem.Label="Show In Taskbar" IsChecked="{Binding ShowInTaskBar}" />
+                        <CheckBox
+                            u:FormItem.Label="Is Close Button Visible"
+                            IsChecked="{Binding IsCloseButtonVisible}"
+                            IsThreeState="True" />
+                        <CheckBox u:FormItem.Label="Modal" IsChecked="{Binding IsModal}" />
+                        <CheckBox u:FormItem.Label="CanDragMove" IsChecked="{Binding CanDragMove}" />
+                        <CheckBox u:FormItem.Label="CanResize" IsChecked="{Binding CanResize}" />
+                        <Button
+                            HorizontalAlignment="Left"
+                            u:FormItem.NoLabel="True"
+                            Command="{Binding ShowDialogCommand}"
+                            Content="Show" />
+                    </u:Form>
+                </TabItem>
+                <TabItem Header="Default Overlay Dialog">
+                    <u:Form
+                        Width="300"
+                        Margin="16,0"
+                        DataContext="{Binding DefaultOverlayDialogDemoViewModel}"
+                        LabelPosition="Top">
+                        <TextBox
+                            HorizontalAlignment="Stretch"
+                            u:FormItem.Label="Title"
+                            Text="{Binding Title}" />
+                        <u:EnumSelector
+                            HorizontalAlignment="Stretch"
+                            u:FormItem.Label="Dialog Mode"
+                            EnumType="u:DialogMode"
+                            Value="{Binding Mode}" />
+                        <u:EnumSelector
+                            HorizontalAlignment="Stretch"
+                            u:FormItem.Label="Dialog Buttons"
+                            EnumType="u:DialogButton"
+                            Value="{Binding Button}" />
+                        <CheckBox
+                            u:FormItem.Label="Is Close Button Visible"
+                            IsChecked="{Binding IsCloseButtonVisible}"
+                            IsThreeState="True" />
+                        <CheckBox u:FormItem.Label="Modal" IsChecked="{Binding IsModal}" />
+                        <CheckBox u:FormItem.Label="Can DragMove" IsChecked="{Binding CanDragMove}" />
+                        <CheckBox u:FormItem.Label="Can LightDismiss" IsChecked="{Binding CanLightDismiss}" />
+                        <CheckBox u:FormItem.Label="FullScreen" IsChecked="{Binding FullScreen}" />
+                        <CheckBox u:FormItem.Label="CanResize" IsChecked="{Binding CanResize}" />
+                        <ToggleSwitch
+                            u:FormItem.Label="Global/Local OverlayHost"
+                            IsChecked="{Binding IsLocal}"
+                            OffContent="Global"
+                            OnContent="Local" />
+                        <u:FormItem>
+                            <u:FormItem.Label>
+                                <StackPanel Orientation="Horizontal">
+                                    <TextBlock Text="Style Class" />
+                                    <PathIcon
+                                        VerticalAlignment="Center"
+                                        Data="{DynamicResource SemiIconHelpCircle}"
+                                        TextElement.FontWeight="Normal"
+                                        Theme="{StaticResource InnerPathIcon}"
+                                        ToolTip.Tip="Pass a Style Class to the created Dialog. In this example, if you set StyleClass as 'Custom', You will get Special Style for OK Button. These styles usually are defined in the root of your App/Window" />
+                                </StackPanel>
+                            </u:FormItem.Label>
+                            <TextBox HorizontalAlignment="Stretch" Text="{Binding StyleClass}" />
+                        </u:FormItem>
+                        <Button
+                            HorizontalAlignment="Left"
+                            u:FormItem.NoLabel="True"
+                            Command="{Binding ShowDialogCommand}"
+                            Content="Show" />
+                    </u:Form>
+                </TabItem>
+                <TabItem Header="Custom Overlay Dialog">
+                    <u:Form
+                        Width="300"
+                        Margin="16,0"
+                        DataContext="{Binding CustomOverlayDialogDemoViewModel}"
+                        LabelPosition="Top">
+                        <TextBox
+                            HorizontalAlignment="Stretch"
+                            u:FormItem.Label="Title"
+                            Text="{Binding Title}" />
+                        <CheckBox
+                            u:FormItem.Label="Is Close Button Visible"
+                            IsChecked="{Binding IsCloseButtonVisible}"
+                            IsThreeState="True" />
+                        <CheckBox u:FormItem.Label="Modal" IsChecked="{Binding IsModal}" />
+                        <CheckBox u:FormItem.Label="Can DragMove" IsChecked="{Binding CanDragMove}" />
+                        <CheckBox u:FormItem.Label="Can LightDismiss" IsChecked="{Binding CanLightDismiss}" />
+                        <CheckBox u:FormItem.Label="FullScreen" IsChecked="{Binding FullScreen}" />
+                        <CheckBox u:FormItem.Label="CanResize" IsChecked="{Binding CanResize}" />
+                        <ToggleSwitch
+                            u:FormItem.Label="Global/Local OverlayHost"
+                            IsChecked="{Binding IsLocal}"
+                            OffContent="Global"
+                            OnContent="Local" />
+                        <Button
+                            HorizontalAlignment="Left"
+                            u:FormItem.NoLabel="True"
+                            Command="{Binding ShowDialogCommand}"
+                            Content="Show" />
+                    </u:Form>
+                </TabItem>
+            </TabControl>
+        </ScrollViewer>
         <Grid Grid.Column="1">
             <Border
-                BorderBrush="{DynamicResource SemiGrey1}"
                 Background="{DynamicResource SemiColorBackground1}"
+                BorderBrush="{DynamicResource SemiGrey1}"
                 BorderThickness="1"
                 ClipToBounds="True"
                 CornerRadius="12">
diff --git a/src/Ursa/Controls/IPv4Box/IPv4BoxInputMethodClient.cs b/src/Ursa/Controls/IPv4Box/IPv4BoxInputMethodClient.cs
index 5bbdf21..7cdbcb7 100644
--- a/src/Ursa/Controls/IPv4Box/IPv4BoxInputMethodClient.cs
+++ b/src/Ursa/Controls/IPv4Box/IPv4BoxInputMethodClient.cs
@@ -4,28 +4,21 @@ using Avalonia.Input.TextInput;
 
 namespace Ursa.Controls;
 
-public class IPv4BoxInputMethodClient:TextInputMethodClient
+public class IPv4BoxInputMethodClient: TextInputMethodClient
 {
     private TextPresenter? _presenter;
-    public override Visual TextViewVisual => _presenter;
+    public override Visual TextViewVisual => _presenter!;
     public override bool SupportsPreedit => false;
     public override bool SupportsSurroundingText => true;
 
-    public override string SurroundingText
-    {
-        get;
-    }
-    public override Rect CursorRectangle { get; }
+    public override string SurroundingText { get; } = null!;
+
+    public override Rect CursorRectangle { get; } = new();
     public override TextSelection Selection { get; set; }
-    private IPv4Box? _parent;
     public void SetPresenter(TextPresenter? presenter)
     {
+        _presenter = presenter;
         this.RaiseTextViewVisualChanged();
         this.RaiseCursorRectangleChanged();
     }
-    
-    private void OnParentPropertyChanged(object? sender, AvaloniaPropertyChangedEventArgs e)
-    {
-        this.RaiseSelectionChanged();
-    }
 }
\ No newline at end of file
diff --git a/src/Ursa/Controls/Marquee/Marquee.cs b/src/Ursa/Controls/Marquee/Marquee.cs
index 4208db0..43c1f17 100644
--- a/src/Ursa/Controls/Marquee/Marquee.cs
+++ b/src/Ursa/Controls/Marquee/Marquee.cs
@@ -124,14 +124,14 @@ public class Marquee : ContentControl
         set => SetValue(SpeedProperty, value);
     }
 
-    private void OnPresenterSizeChanged(object sender, SizeChangedEventArgs e)
+    private void OnPresenterSizeChanged(object? sender, SizeChangedEventArgs e)
     {
         InvalidatePresenterPosition();
     }
 
     
 
-    private void TimerOnTick(object sender, System.EventArgs e)
+    private void TimerOnTick(object? sender, System.EventArgs e)
     {
         if (Presenter is null) return;
         var layoutValues = Dispatcher.UIThread.Invoke(GetLayoutValues);
@@ -177,11 +177,13 @@ public class Marquee : ContentControl
         {
             Direction.Up or Direction.Down => GetHorizontalOffset(values.Bounds, values.PresenterSize, values.HorizontalAlignment),
             Direction.Left or Direction.Right => values.Left,
+            _ => throw new NotImplementedException(),
         };
         var verticalOffset = values.Direction switch
         {
             Direction.Up or Direction.Down => values.Top,
             Direction.Left or Direction.Right => GetVerticalOffset(values.Bounds, values.PresenterSize, values.VerticalAlignment),
+            _ => throw new NotImplementedException(),
         };
         if (horizontalOffset is double.NaN) horizontalOffset = 0.0;
         if (verticalOffset is double.NaN) verticalOffset = 0.0;
diff --git a/src/Ursa/Controls/PathPicker/PathPicker.cs b/src/Ursa/Controls/PathPicker/PathPicker.cs
index d21b981..2da25f0 100644
--- a/src/Ursa/Controls/PathPicker/PathPicker.cs
+++ b/src/Ursa/Controls/PathPicker/PathPicker.cs
@@ -204,10 +204,10 @@ public class PathPicker : TemplatedControl
             nameof(FilePickerFileTypes.ImagePng) => FilePickerFileTypes.ImagePng,
             nameof(FilePickerFileTypes.ImageWebp) => FilePickerFileTypes.ImageWebp,
             nameof(FilePickerFileTypes.TextPlain) => FilePickerFileTypes.TextPlain,
-            _ => parse()
+            _ => Parse()
         };
 
-        FilePickerFileType parse()
+        FilePickerFileType Parse()
         {
             var list = str.Split(',');
             return new FilePickerFileType(list.First())
@@ -248,7 +248,7 @@ public class PathPicker : TemplatedControl
                         FileTypeFilter = ParseFileTypes(FileFilter)
                     };
                     var resFiles = await storageProvider.OpenFilePickerAsync(filePickerOpenOptions);
-                    UpdateSelectedPaths(resFiles.Select(x => x.TryGetLocalPath()).ToArray()!);
+                    UpdateSelectedPaths(resFiles.Select(x => x.TryGetLocalPath()).ToArray());
                     break;
                 case UsePickerTypes.SaveFile:
                     FilePickerSaveOptions filePickerSaveOptions = new()
@@ -263,9 +263,7 @@ public class PathPicker : TemplatedControl
 
                     var path = (await storageProvider.SaveFilePickerAsync(filePickerSaveOptions))
                         ?.TryGetLocalPath();
-                    UpdateSelectedPaths(string.IsNullOrEmpty(path)
-                        ? Array.Empty<string>()
-                        : [path]);
+                    UpdateSelectedPaths([path]);
                     break;
                 case UsePickerTypes.OpenFolder:
                     FolderPickerOpenOptions folderPickerOpenOptions = new()
@@ -277,7 +275,7 @@ public class PathPicker : TemplatedControl
                         SuggestedFileName = SuggestedFileName
                     };
                     var resFolder = await storageProvider.OpenFolderPickerAsync(folderPickerOpenOptions);
-                    UpdateSelectedPaths(resFolder.Select(x => x.TryGetLocalPath()).ToArray()!);
+                    UpdateSelectedPaths(resFolder.Select(x => x.TryGetLocalPath()).ToArray());
                     break;
                 default:
                     throw new ArgumentOutOfRangeException();
@@ -298,9 +296,10 @@ public class PathPicker : TemplatedControl
         }
     }
 
-    private void UpdateSelectedPaths(IReadOnlyList<string> newList)
+    private void UpdateSelectedPaths(IReadOnlyList<string?> newList)
     {
-        if (newList.Count != 0 || IsClearSelectionOnCancel && newList.Count == 0)
-            SelectedPaths = newList;
+        var nonNullList = newList.Where(x => x is not null).Select(x => x!).ToList();
+        if (nonNullList.Count != 0 || IsClearSelectionOnCancel && nonNullList.Count == 0)
+            SelectedPaths = nonNullList;
     }
 }
\ No newline at end of file
diff --git a/tests/HeadlessTest.Ursa/Controls/DateTimePicker/DatePickerTests.cs b/tests/HeadlessTest.Ursa/Controls/DateTimePicker/DatePickerTests.cs
index 005e16a..c0387cf 100644
--- a/tests/HeadlessTest.Ursa/Controls/DateTimePicker/DatePickerTests.cs
+++ b/tests/HeadlessTest.Ursa/Controls/DateTimePicker/DatePickerTests.cs
@@ -7,7 +7,6 @@ using Avalonia.Input;
 using Avalonia.Layout;
 using Avalonia.LogicalTree;
 using Avalonia.Threading;
-using Avalonia.VisualTree;
 using HeadlessTest.Ursa.TestHelpers;
 using Ursa.Controls;
 using DatePicker = Ursa.Controls.DatePicker;
@@ -176,7 +175,7 @@ public class DatePickerTests
         window.MouseDown(new Point(10, 10), MouseButton.Left);
         Dispatcher.UIThread.RunJobs();
         var popup = picker.GetTemplateChildOfType<Popup>(DatePicker.PART_Popup);
-        var calendar = popup.GetLogicalDescendants().OfType<CalendarView>().FirstOrDefault();
+        var calendar = popup?.GetLogicalDescendants().OfType<CalendarView>().FirstOrDefault();
         calendar?.RaiseEvent(new CalendarDayButtonEventArgs(new DateTime(2025, 2, 17))
             { RoutedEvent = CalendarView.DateSelectedEvent }); 
         Dispatcher.UIThread.RunJobs();
@@ -203,7 +202,7 @@ public class DatePickerTests
         window.MouseDown(new Point(10, 10), MouseButton.Left);
         Dispatcher.UIThread.RunJobs();
         var popup = picker.GetTemplateChildOfType<Popup>(DatePicker.PART_Popup);
-        var calendar = popup.GetLogicalDescendants().OfType<CalendarView>().FirstOrDefault();
+        var calendar = popup?.GetLogicalDescendants().OfType<CalendarView>().FirstOrDefault();
         calendar?.RaiseEvent(new CalendarDayButtonEventArgs(new DateTime(2025, 2, 17))
             { RoutedEvent = CalendarView.DateSelectedEvent }); 
         Dispatcher.UIThread.RunJobs();
@@ -270,13 +269,13 @@ public class DatePickerTests
             HorizontalAlignment = HorizontalAlignment.Left,
             VerticalAlignment = VerticalAlignment.Top
         };
-        var focustextBox = new TextBox();
+        var focusTextBox = new TextBox();
         window.Content = new StackPanel()
         {
             Children =
             {
                 picker,
-                focustextBox,
+                focusTextBox,
             }
         };
         window.Show();
@@ -289,7 +288,7 @@ public class DatePickerTests
         Dispatcher.UIThread.RunJobs();
         Assert.Equal(new DateTime(2025, 2, 18), picker.SelectedDate);
         textBox?.SetValue(TextBox.TextProperty, "2025-02-18-");
-        focustextBox.Focus();
+        focusTextBox.Focus();
         Dispatcher.UIThread.RunJobs();
         Assert.Null(picker.SelectedDate);
     }
@@ -356,7 +355,6 @@ public class DatePickerTests
         var position = nextButton.TranslatePoint(new Point(5, 5), window);
         Assert.NotNull(position);
         window.MouseDown(new Point(10, 10), MouseButton.Left);
-        var renderRoot = popup.GetVisualRoot();
         
         Dispatcher.UIThread.RunJobs();
         Assert.True(picker.IsDropdownOpen);
diff --git a/tests/HeadlessTest.Ursa/Controls/DrawerTests/CloseEventTest/DrawerCloseEventTest.cs b/tests/HeadlessTest.Ursa/Controls/DrawerTests/CloseEventTest/DrawerCloseEventTest.cs
index 9dddfbd..05b7a00 100644
--- a/tests/HeadlessTest.Ursa/Controls/DrawerTests/CloseEventTest/DrawerCloseEventTest.cs
+++ b/tests/HeadlessTest.Ursa/Controls/DrawerTests/CloseEventTest/DrawerCloseEventTest.cs
@@ -1,5 +1,4 @@
-using Avalonia.Controls;
-using Avalonia.Headless.XUnit;
+using Avalonia.Headless.XUnit;
 using Avalonia.Threading;
 using Avalonia.VisualTree;
 using Ursa.Controls;
@@ -17,11 +16,13 @@ public class DrawerCloseEventTest
         };
         testWindow.Show();
         DrawerCloseTestPopupControl level1 = new();
-        OverlayDialog.ShowCustomModal<object>(level1, new DrawerCloseTestPopupControlVM(), "root");
+        _ = OverlayDialog.ShowCustomModal<object>(level1, new DrawerCloseTestPopupControlVM(), "root");
         level1.OpenPopup();
         var level2 = level1.Popup;
+        Assert.NotNull(level2);
         level2.OpenPopup();
         var level3 = level2.Popup;
+        Assert.NotNull(level3);
         level2.ClosePopup();
         await Task.Delay(TimeSpan.FromSeconds(1));
         Dispatcher.UIThread.RunJobs();
@@ -47,11 +48,13 @@ public class DrawerCloseEventTest
         Assert.Equal(level2.LResult, level2.RResult);
         Assert.Equal(level3.LResult, level3.RResult);
 
-        OverlayDialog.ShowCustomModal<object>(level1, new DrawerCloseTestPopupControlVM(), "root");
+        _ = OverlayDialog.ShowCustomModal<object>(level1, new DrawerCloseTestPopupControlVM(), "root");
         level1.OpenPopup();
         level2 = level1.Popup;
+        Assert.NotNull(level2);
         level2.OpenPopup();
         level3 = level2.Popup;
+        Assert.NotNull(level3);
         level3.OpenPopup();
         level1.Close();
         await Task.Delay(TimeSpan.FromSeconds(1));
diff --git a/tests/HeadlessTest.Ursa/Controls/DrawerTests/CloseEventTest/DrawerCloseTestPopupControl.axaml.cs b/tests/HeadlessTest.Ursa/Controls/DrawerTests/CloseEventTest/DrawerCloseTestPopupControl.axaml.cs
index 7f9bec4..be24da9 100644
--- a/tests/HeadlessTest.Ursa/Controls/DrawerTests/CloseEventTest/DrawerCloseTestPopupControl.axaml.cs
+++ b/tests/HeadlessTest.Ursa/Controls/DrawerTests/CloseEventTest/DrawerCloseTestPopupControl.axaml.cs
@@ -1,11 +1,4 @@
-using System;
-using System.ComponentModel;
-using System.IO;
-using System.Runtime.CompilerServices;
-using Avalonia;
-using Avalonia.Controls;
-using Avalonia.Interactivity;
-using Avalonia.Markup.Xaml;
+using Avalonia.Controls;
 using Ursa.Controls;
 
 namespace HeadlessTest.Ursa.Controls;
@@ -19,7 +12,7 @@ public partial class DrawerCloseTestPopupControl : UserControl
     }
 
     private readonly string _hostid = Path.GetRandomFileName();
-    public DrawerCloseTestPopupControl Popup { get; set; }
+    public DrawerCloseTestPopupControl? Popup { get; set; }
     public int LResult { get; set; }
     public int RResult { get; set; }
 
@@ -32,7 +25,7 @@ public partial class DrawerCloseTestPopupControl : UserControl
 
     public void ClosePopup()
     {
-        (Popup.DataContext as DrawerCloseTestPopupControlVM)?.Close();
+        (Popup?.DataContext as DrawerCloseTestPopupControlVM)?.Close();
     }
 
 
diff --git a/tests/HeadlessTest.Ursa/Controls/DrawerTests/MeasureTest/DrawerMeasureTest.cs b/tests/HeadlessTest.Ursa/Controls/DrawerTests/MeasureTest/DrawerMeasureTest.cs
index 1a1b409..44fbe40 100644
--- a/tests/HeadlessTest.Ursa/Controls/DrawerTests/MeasureTest/DrawerMeasureTest.cs
+++ b/tests/HeadlessTest.Ursa/Controls/DrawerTests/MeasureTest/DrawerMeasureTest.cs
@@ -29,7 +29,7 @@ public class DrawerMeasureTest
         };
         window.Show();
         Dispatcher.UIThread.RunJobs();
-        Drawer.ShowModal(textBlock, "hello world", null,
+        _ = Drawer.ShowModal(textBlock, "hello world", null,
             new DrawerOptions { Position = position, TopLevelHashCode = window.GetHashCode() });
         await Task.Delay(TimeSpan.FromSeconds(0.1));
         var dialogControl = window.GetVisualDescendants().OfType<DefaultDrawerControl>().SingleOrDefault();
@@ -57,7 +57,6 @@ public class DrawerMeasureTest
         };
         window.Show();
         Dispatcher.UIThread.RunJobs();
-        var d = window.GetVisualDescendants().ToList();
         Drawer.ShowCustom(textBlock, "hello world", null,
             new DrawerOptions { Position = position, TopLevelHashCode = window.GetHashCode() });
         await Task.Delay(TimeSpan.FromSeconds(0.1));
diff --git a/tests/HeadlessTest.Ursa/Controls/PaginationTests/PaginationTests.cs b/tests/HeadlessTest.Ursa/Controls/PaginationTests/PaginationTests.cs
index 9f7ad87..5a5b65b 100644
--- a/tests/HeadlessTest.Ursa/Controls/PaginationTests/PaginationTests.cs
+++ b/tests/HeadlessTest.Ursa/Controls/PaginationTests/PaginationTests.cs
@@ -403,7 +403,8 @@ public class PaginationTests
         window.Show();
         Dispatcher.UIThread.RunJobs();
         var buttonsPanel = pagination.GetTemplateChildOfType<Panel>(Pagination.PART_ButtonPanel);
-        var buttons = buttonsPanel.Children.OfType<PaginationButton>().ToList();
+        var buttons = buttonsPanel?.Children.OfType<PaginationButton>().ToList();
+        Assert.NotNull(buttons);
         buttons[0].RaiseEvent(new RoutedEventArgs(Button.ClickEvent));
         Dispatcher.UIThread.RunJobs();
         Assert.Equal(1, count);