Add MVVM-pure clipboard copy for history: hover-only copy button with flyout on Desktop/Web and long-press/right-click context menu; View writes to clipboard via CopyRequested event

src/AdvancedCalculator/ViewModels/MainViewModel.cs

@@ -11,6 +11,7 @@ namespace AdvancedCalculator.ViewModels;
 public partial class MainViewModel : ViewModelBase
 {
     private readonly ICalculatorService _calculatorService;
+    public event EventHandler<string>? CopyRequested;
 
     public MainViewModel()
         : this(new CalculatorService())
@@ -97,4 +98,32 @@ public partial class MainViewModel : ViewModelBase
         InputText = string.Empty;
         SelectedHistoryIndex = History.Count - 1;
     }
+
+    // Copy helpers (MVVM-pure): build text in VM, View handles clipboard via CopyRequested
+    [RelayCommand]
+    private void CopyHistoryInput(HistoryItem? item)
+    {
+        if (item is null || string.IsNullOrWhiteSpace(item.Input)) return;
+        CopyRequested?.Invoke(this, item.Input);
+    }
+
+    [RelayCommand]
+    private void CopyHistoryOutput(HistoryItem? item)
+    {
+        if (item is null || string.IsNullOrWhiteSpace(item.Output)) return;
+        CopyRequested?.Invoke(this, item.Output);
+    }
+
+    [RelayCommand]
+    private void CopyHistoryBoth(HistoryItem? item)
+    {
+        if (item is null) return;
+        var input = item.Input?.Trim();
+        var output = item.Output?.Trim();
+        if (string.IsNullOrEmpty(input) && string.IsNullOrEmpty(output)) return;
+        if (string.IsNullOrEmpty(input)) { CopyRequested?.Invoke(this, output!); return; }
+        if (string.IsNullOrEmpty(output)) { CopyRequested?.Invoke(this, input!); return; }
+
+        CopyRequested?.Invoke(this, $"{input} = {output}");
+    }
 }

src/AdvancedCalculator/Views/MainView.axaml

@@ -70,28 +70,94 @@
 		<SplitView.Content>
 			<Grid RowDefinitions="*,Auto">
 				<!-- History -->
-				<Grid Grid.Row="0">
+                <Grid Grid.Row="0">
-					<ListBox ItemsSource="{Binding History}" SelectedIndex="{Binding SelectedHistoryIndex}"
+                    <ListBox ItemsSource="{Binding History}" SelectedIndex="{Binding SelectedHistoryIndex}"
-							 AutomationProperties.Name="History list">
+                         AutomationProperties.Name="History list">
-						<ListBox.ItemTemplate>
+                        <ListBox.ItemTemplate>
-							<DataTemplate x:DataType="m:HistoryItem">
+                            <DataTemplate x:DataType="m:HistoryItem">
-								<Grid ColumnDefinitions="Auto,*" Margin="4,2">
+                                <!-- Root row container so we can bind IsPointerOver for hover-only controls -->
-									<TextBlock FontFamily="{StaticResource MDI}" Text="{x:Static m:IconFont.ArrowRightDropCircle}"
+                                <Grid x:Name="HistoryRow" ColumnDefinitions="Auto,*,Auto" Margin="4,2">
-											   FontSize="{DynamicResource IconSizeM}" VerticalAlignment="Center" Margin="0,0,8,0" />
+                                    <TextBlock Grid.Column="0" FontFamily="{StaticResource MDI}" Text="{x:Static m:IconFont.ArrowRightDropCircle}"
-									<StackPanel Grid.Column="1">
+                                               FontSize="{DynamicResource IconSizeM}" VerticalAlignment="Center" Margin="0,0,8,0" />
-										<TextBlock Text="{Binding Input}" MaxLines="3" />
+                                    <StackPanel Grid.Column="1">
-										<TextBlock Text="{Binding Output}" FontWeight="Bold" MaxLines="2" />
+                                        <TextBlock Text="{Binding Input}" MaxLines="3" />
-									</StackPanel>
+                                        <TextBlock Text="{Binding Output}" FontWeight="Bold" MaxLines="2" />
-								</Grid>
+                                    </StackPanel>
-							</DataTemplate>
+
-						</ListBox.ItemTemplate>
+                                    <!-- Hover-only copy button for Desktop/Web with options flyout -->
-					</ListBox>
+                                    <Button Grid.Column="2"
-					<TextBlock Text="No history yet. Enter an expression and Evaluate."
+                                            IsVisible="{Binding #HistoryRow.IsPointerOver}"
-							   IsVisible="{Binding History.Count, Converter={StaticResource IsZeroConverter}}"
+                                            Margin="8,0,0,0"
-							   IsHitTestVisible="False"
+                                            Padding="8,4"
-							   Opacity="0.6"
+                                            MinHeight="28"
-							   HorizontalAlignment="Center" VerticalAlignment="Center" />
+                                            Background="Transparent"
-				</Grid>
+                                            AutomationProperties.Name="Copy options">
+                                        <Button.Flyout>
+                                            <Flyout Placement="BottomEdgeAlignedRight">
+                                                <StackPanel>
+                                                    <Button x:DataType="vm:MainViewModel"
+                                                            DataContext="{Binding #Root.DataContext}"
+                                                            Command="{Binding CopyHistoryInputCommand}"
+                                                            CommandParameter="{Binding #HistoryRow.DataContext}"
+                                                            AutomationProperties.Name="Copy input"
+                                                            Background="Transparent" BorderThickness="0" Padding="8,4">
+                                                        <TextBlock Text="Copy Input"/>
+                                                    </Button>
+                                                    <Button x:DataType="vm:MainViewModel"
+                                                            DataContext="{Binding #Root.DataContext}"
+                                                            Command="{Binding CopyHistoryOutputCommand}"
+                                                            CommandParameter="{Binding #HistoryRow.DataContext}"
+                                                            AutomationProperties.Name="Copy output"
+                                                            Background="Transparent" BorderThickness="0" Padding="8,4">
+                                                        <TextBlock Text="Copy Output"/>
+                                                    </Button>
+                                                    <Button x:DataType="vm:MainViewModel"
+                                                            DataContext="{Binding #Root.DataContext}"
+                                                            Command="{Binding CopyHistoryBothCommand}"
+                                                            CommandParameter="{Binding #HistoryRow.DataContext}"
+                                                            AutomationProperties.Name="Copy input and output"
+                                                            Background="Transparent" BorderThickness="0" Padding="8,4">
+                                                        <TextBlock Text="Copy Input = Output"/>
+                                                    </Button>
+                                                </StackPanel>
+                                            </Flyout>
+                                        </Button.Flyout>
+                                        <TextBlock Text="Copy"/>
+                                    </Button>
+
+                                    <!-- Context menu for right-click / long-press (Android) -->
+                                    <Grid.ContextMenu>
+                                        <ContextMenu>
+                                            <MenuItem x:DataType="vm:MainViewModel"
+                                                      DataContext="{Binding #Root.DataContext}"
+                                                      Header="Copy Input"
+                                                      Command="{Binding CopyHistoryInputCommand}"
+                                                      CommandParameter="{Binding #HistoryRow.DataContext}"
+                                                      />
+                                            <MenuItem x:DataType="vm:MainViewModel"
+                                                      DataContext="{Binding #Root.DataContext}"
+                                                      Header="Copy Output"
+                                                      Command="{Binding CopyHistoryOutputCommand}"
+                                                      CommandParameter="{Binding #HistoryRow.DataContext}"
+                                                      />
+                                            <MenuItem x:DataType="vm:MainViewModel"
+                                                      DataContext="{Binding #Root.DataContext}"
+                                                      Header="Copy Input = Output"
+                                                      Command="{Binding CopyHistoryBothCommand}"
+                                                      CommandParameter="{Binding #HistoryRow.DataContext}"
+                                                      />
+                                        </ContextMenu>
+                                    </Grid.ContextMenu>
+                                </Grid>
+                            </DataTemplate>
+                        </ListBox.ItemTemplate>
+                    </ListBox>
+                    <TextBlock Text="No history yet. Enter an expression and Evaluate."
+                                   IsVisible="{Binding History.Count, Converter={StaticResource IsZeroConverter}}"
+                                   IsHitTestVisible="False"
+                                   Opacity="0.6"
+                                   HorizontalAlignment="Center" VerticalAlignment="Center" />
+                </Grid>
 
 				<!-- Input Row -->
 				<Grid Grid.Row="1" ColumnDefinitions="Auto,Auto,*,Auto" Margin="4">

src/AdvancedCalculator/Views/MainView.axaml.cs

@@ -1,4 +1,7 @@
-using Avalonia.Controls;
+using System;
+using Avalonia;
+using Avalonia.Controls;
+using AdvancedCalculator.ViewModels;
 
 namespace AdvancedCalculator.Views;
 
@@ -7,5 +10,41 @@ public partial class MainView : UserControl
     public MainView()
     {
         InitializeComponent();
+        this.AttachedToVisualTree += OnAttachedToVisualTree;
+        this.DetachedFromVisualTree += OnDetachedFromVisualTree;
+    }
+
+    private MainViewModel? _vm;
+
+    private void OnAttachedToVisualTree(object? sender, VisualTreeAttachmentEventArgs e)
+    {
+        _vm = DataContext as MainViewModel;
+        if (_vm is not null)
+        {
+            _vm.CopyRequested += OnCopyRequested;
+        }
+    }
+
+    private void OnDetachedFromVisualTree(object? sender, VisualTreeAttachmentEventArgs e)
+    {
+        if (_vm is not null)
+        {
+            _vm.CopyRequested -= OnCopyRequested;
+        }
+        _vm = null;
+    }
+
+    private async void OnCopyRequested(object? sender, string text)
+    {
+        var top = TopLevel.GetTopLevel(this);
+        if (top?.Clipboard is null) return;
+        try
+        {
+            await top.Clipboard.SetTextAsync(text);
+        }
+        catch
+        {
+            // Ignore clipboard errors; e.g., browser permission or missing gesture context
+        }
     }
 }