fix:should be PathPickerForListView in demo

add:Maybe we can add a command demo here to show how to trigger the bound command.
change:I think these two themes should be merged, and the "AcceptReturn" should just be controlled by "AllowMultiple"
add:One more thing, we should add a property to control what to do when user cancelled a selection. Sometimes I just want to keep the original selection.

demo/Ursa.Demo/Pages/PathPickerDemo.axaml

@@ -32,6 +32,10 @@
                     <ToggleButton Name="AllowMultiple" Content="AllowMultiple" u:FormItem.NoLabel="True"
                                   HorizontalAlignment="Stretch">
                     </ToggleButton>
+                    <ToggleButton Name="IsCancelingPickerAlsoTriggers" Content="Canceling selection also triggers the Command."
+                                  u:FormItem.NoLabel="True"
+                                  HorizontalAlignment="Stretch">
+                    </ToggleButton>
                     <u:EnumSelector Name="UsePickerType" EnumType="u:UsePickerTypes" u:FormItem.Label="UsePickerType"></u:EnumSelector>
                 </u:Form>
             </StackPanel>
@@ -47,20 +51,9 @@
                                   AllowMultiple="{Binding #AllowMultiple.IsChecked}"
                                   UsePickerType="{Binding #UsePickerType.Value}"
                                   SelectedPathsText="{Binding Path,Mode=OneWayToSource}"
-                                  SelectedPaths="{Binding Paths,Mode=OneWayToSource}">
+                                  SelectedPaths="{Binding Paths,Mode=OneWayToSource}"
-                    </u:PathPicker>
+                                  Command="{Binding SelectedCommand}"
-                </HeaderedContentControl>
+                                  IsCancelingPickerAlsoTriggers="{Binding #IsCancelingPickerAlsoTriggers.IsChecked}">
-                <HeaderedContentControl Header="PathPickerForMultipleText">
-                    <u:PathPicker Title="{Binding #Title.Text}"
-                                  Theme="{DynamicResource PathPickerForMultipleText}"
-                                  SuggestedFileName="{Binding #SuggestedFileName.Text}"
-                                  SuggestedStartPath="{Binding #SuggestedStartPath.Text}"
-                                  FileFilter="{Binding #FileFilter.Text}"
-                                  DefaultFileExtension="{Binding #DefaultFileExtension.Text}"
-                                  AllowMultiple="{Binding #AllowMultiple.IsChecked}"
-                                  UsePickerType="{Binding #UsePickerType.Value}"
-                                  SelectedPathsText="{Binding Path,Mode=OneWayToSource}"
-                                  SelectedPaths="{Binding Paths,Mode=OneWayToSource}">
                     </u:PathPicker>
                 </HeaderedContentControl>
                 <HeaderedContentControl Header="PathPickerOnlyButton">
@@ -73,11 +66,13 @@
                                   AllowMultiple="{Binding #AllowMultiple.IsChecked}"
                                   UsePickerType="{Binding #UsePickerType.Value}"
                                   SelectedPathsText="{Binding Path,Mode=OneWayToSource}"
-                                  SelectedPaths="{Binding Paths,Mode=OneWayToSource}">
+                                  SelectedPaths="{Binding Paths,Mode=OneWayToSource}"
+                                  Command="{Binding SelectedCommand}"
+                                  IsCancelingPickerAlsoTriggers="{Binding #IsCancelingPickerAlsoTriggers.IsChecked}">
                     </u:PathPicker>
                 </HeaderedContentControl>
                 <HeaderedContentControl Header="PathPickerForListView">
-                    <u:PathPicker Theme="{DynamicResource PathPickerForList}"
+                    <u:PathPicker Theme="{DynamicResource PathPickerForListView}"
                                   Title="{Binding #Title.Text}"
                                   SuggestedFileName="{Binding #SuggestedFileName.Text}"
                                   SuggestedStartPath="{Binding #SuggestedStartPath.Text}"
@@ -86,13 +81,16 @@
                                   AllowMultiple="{Binding #AllowMultiple.IsChecked}"
                                   UsePickerType="{Binding #UsePickerType.Value}"
                                   SelectedPathsText="{Binding Path,Mode=OneWayToSource}"
-                                  SelectedPaths="{Binding Paths,Mode=OneWayToSource}">
+                                  SelectedPaths="{Binding Paths,Mode=OneWayToSource}"
+                                  Command="{Binding SelectedCommand}"
+                                  IsCancelingPickerAlsoTriggers="{Binding #IsCancelingPickerAlsoTriggers.IsChecked}">
                     </u:PathPicker>
                 </HeaderedContentControl>
             </StackPanel>
         </ScrollViewer>
         <ScrollViewer Grid.Column="1" Grid.Row="0" Grid.RowSpan="2">
             <StackPanel Spacing="1">
+                <TextBlock Text="{Binding CommandTriggerCount,StringFormat='Command Trigger Count:{0}'}"></TextBlock>
                 <HeaderedContentControl Header="SelectedPathsText">
                     <TextBox Name="SelectedPath" u:FormItem.Label="SelectedPath" IsReadOnly="True"
                              Text="{Binding Path}">

demo/Ursa.Demo/ViewModels/PathPickerDemoViewModel.cs

@@ -1,5 +1,6 @@
 using System.Collections.Generic;
 using CommunityToolkit.Mvvm.ComponentModel;
+using CommunityToolkit.Mvvm.Input;
 
 namespace Ursa.Demo.ViewModels;
 
@@ -7,4 +8,11 @@ public partial class PathPickerDemoViewModel : ViewModelBase
 {
     [ObservableProperty] private string? _path;
     [ObservableProperty] private IReadOnlyList<string>? _paths;
+    [ObservableProperty] private int _commandTriggerCount = 0;
+
+    [RelayCommand]
+    private void Selected(IReadOnlyList<string> paths)
+    {
+        CommandTriggerCount++;
+    }
 }

src/Ursa.Themes.Semi/Controls/PathPicker.axaml

@@ -11,32 +11,31 @@
                             Content="{TemplateBinding Title}"
                             Margin="1,0,0,0">
                     </Button>
-                    <TextBox DockPanel.Dock="Left"
+                    <TextBox Name="PART_TextBox"
+                             DockPanel.Dock="Left"
+                             AcceptsReturn="{TemplateBinding AllowMultiple}"
                              Text="{TemplateBinding SelectedPathsText,Mode=TwoWay}">
                     </TextBox>
                 </DockPanel>
             </ControlTemplate>
         </Setter>
-    </ControlTheme>
 
-    <ControlTheme x:Key="PathPickerForMultipleText" TargetType="ursa:PathPicker">
+        <Style Selector="^[AllowMultiple=False]">
-        <Setter Property="Template">
+            <Style Selector="^ /template/ Button#PART_Button">
-            <ControlTemplate>
+                <Setter Property="DockPanel.Dock" Value="Right"></Setter>
-                <DockPanel HorizontalAlignment="{TemplateBinding HorizontalAlignment}"
+            </Style>
-                           VerticalAlignment="{TemplateBinding VerticalAlignment}">
+            <Style Selector="^ /template/ TextBox#PART_TextBox">
-                    <Button Name="PART_Button"
+                <Setter Property="DockPanel.Dock" Value="Left"></Setter>
-                            DockPanel.Dock="Top"
+            </Style>
-                            HorizontalAlignment="Stretch"
+        </Style>
-                            Content="{TemplateBinding Title}"
+        <Style Selector="^[AllowMultiple=True]">
-                            Margin="0,0,0,1">
+            <Style Selector="^ /template/ Button#PART_Button">
-                    </Button>
+                <Setter Property="DockPanel.Dock" Value="Top"></Setter>
-                    <TextBox DockPanel.Dock="Bottom"
+            </Style>
-                             Text="{TemplateBinding SelectedPathsText,Mode=TwoWay}"
+            <Style Selector="^ /template/ TextBox#PART_TextBox">
-                             AcceptsReturn="True">
+                <Setter Property="DockPanel.Dock" Value="Bottom"></Setter>
-                    </TextBox>
+            </Style>
-                </DockPanel>
+        </Style>
-            </ControlTemplate>
-        </Setter>
     </ControlTheme>
 
 

src/Ursa/Controls/PathPicker/PathPicker.cs

@@ -54,6 +54,16 @@ public class PathPicker : TemplatedControl
         AvaloniaProperty.Register<PathPicker, string?>(
             nameof(SelectedPathsText), defaultBindingMode: BindingMode.TwoWay);
 
+    public static readonly StyledProperty<bool> IsCancelingPickerAlsoTriggersProperty =
+        AvaloniaProperty.Register<PathPicker, bool>(
+            nameof(IsCancelingPickerAlsoTriggers));
+
+    public bool IsCancelingPickerAlsoTriggers
+    {
+        get => GetValue(IsCancelingPickerAlsoTriggersProperty);
+        set => SetValue(IsCancelingPickerAlsoTriggersProperty, value);
+    }
+
     public string? SelectedPathsText
     {
         get => GetValue(SelectedPathsTextProperty);
@@ -129,7 +139,7 @@ public class PathPicker : TemplatedControl
         {
             _twoConvertLock = true;
             var stringBuilder = new StringBuilder();
-            stringBuilder.Append(SelectedPaths.FirstOrDefault());
+            stringBuilder.Append(SelectedPaths[0]);
             foreach (var item in SelectedPaths.Skip(1))
             {
                 stringBuilder.AppendLine(item);
@@ -268,7 +278,7 @@ public class PathPicker : TemplatedControl
                     throw new ArgumentOutOfRangeException();
             }
 
-            if (SelectedPaths.Count != 0)
+            if (SelectedPaths.Count != 0 || IsCancelingPickerAlsoTriggers)
                 Command?.Execute(SelectedPaths);
         }
         catch (Exception exception)