added Drag+Drop sample

samples/ControlCatalog/ControlCatalog.csproj

@@ -23,6 +23,8 @@
   </PropertyGroup>
   <ItemGroup>
     <None Remove="Pages\ContextMenuPage.xaml" />
+    <None Remove="Pages\DragAndDropPage.cs" />
+    <None Remove="Pages\DragAndDropPage.xaml" />
   </ItemGroup>
   <ItemGroup>
     <!-- A reference to the entire .NET Framework is automatically included -->
@@ -35,6 +37,9 @@
     <EmbeddedResource Include="DecoratedWindow.xaml">
       <SubType>Designer</SubType>
     </EmbeddedResource>
+    <EmbeddedResource Include="Pages\DragAndDropPage.xaml">
+      <SubType>Designer</SubType>
+    </EmbeddedResource>
     <EmbeddedResource Include="Pages\ButtonSpinnerPage.xaml">
       <SubType>Designer</SubType>
     </EmbeddedResource>
@@ -140,6 +145,9 @@
     <Compile Include="Pages\CheckBoxPage.xaml.cs">
       <DependentUpon>CheckBoxPage.xaml</DependentUpon>
     </Compile>
+    <Compile Include="Pages\DragAndDropPage.cs">
+      <DependentUpon>DragAndDropPage.xaml</DependentUpon>
+    </Compile>
     <Compile Include="Pages\DropDownPage.xaml.cs">
       <DependentUpon>DropDownPage.xaml</DependentUpon>
     </Compile>

samples/ControlCatalog/MainView.xaml

@@ -15,6 +15,7 @@
     <TabItem Header="CheckBox"><pages:CheckBoxPage/></TabItem>
     <TabItem Header="ContextMenu"><pages:ContextMenuPage/></TabItem>
     <TabItem Header="DatePicker"><pages:DatePickerPage/></TabItem>
+    <TabItem Header="Drag+Drop"><pages:DragAndDropPage/></TabItem>
     <TabItem Header="DropDown"><pages:DropDownPage/></TabItem>
     <TabItem Header="Expander"><pages:ExpanderPage/></TabItem>
     <TabItem Header="Image"><pages:ImagePage/></TabItem>

samples/ControlCatalog/Pages/DragAndDropPage.cs

@@ -0,0 +1,71 @@
+using Avalonia.Controls;
+using Avalonia.Input.DragDrop;
+using Avalonia.Markup.Xaml;
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace ControlCatalog.Pages
+{
+    public class DragAndDropPage : UserControl
+    {
+        private TextBlock _DropState;
+        private TextBlock _DragState;
+        private Border _DragMe;
+        private int DragCount = 0;
+
+        public DragAndDropPage()
+        {
+            this.InitializeComponent();
+
+            _DragMe.PointerPressed += DoDrag;
+
+            AddHandler(DragDrop.DropEvent, Drop);
+            AddHandler(DragDrop.DragOverEvent, DragOver);
+        }
+
+        private async void DoDrag(object sender, Avalonia.Input.PointerPressedEventArgs e)
+        {
+            DataObject dragData = new DataObject();
+            dragData.Set(DataFormats.Text, $"You have dragged text {++DragCount} times");
+
+            var result = await DragDrop.DoDragDrop(dragData, DragDropEffects.Copy);
+            switch(result)
+            {
+                case DragDropEffects.Copy:
+                    _DragState.Text = "The text was copied"; break;
+                case DragDropEffects.Link:
+                    _DragState.Text = "The text was linked"; break;
+                case DragDropEffects.None:
+                    _DragState.Text = "The drag operation was canceled"; break;
+            }
+        }
+
+        private void DragOver(object sender, DragEventArgs e)
+        {
+            // Only allow Copy or Link as Drop Operations.
+            e.DragEffects = e.DragEffects & (DragDropEffects.Copy | DragDropEffects.Link);
+
+            // Only allow if the dragged data contains text or filenames.
+            if (!e.Data.Contains(DataFormats.Text) && !e.Data.Contains(DataFormats.FileNames))
+                e.DragEffects = DragDropEffects.None; 
+        }
+
+        private void Drop(object sender, DragEventArgs e)
+        {
+            if (e.Data.Contains(DataFormats.Text))
+                _DropState.Text = e.Data.GetText();
+            else if (e.Data.Contains(DataFormats.FileNames))
+                _DropState.Text = string.Join(Environment.NewLine, e.Data.GetFileNames());
+        }
+
+        private void InitializeComponent()
+        {
+            AvaloniaXamlLoader.Load(this);
+
+            _DropState = this.Find<TextBlock>("DropState");
+            _DragState = this.Find<TextBlock>("DragState");
+            _DragMe = this.Find<Border>("DragMe");
+        }
+    }
+}

samples/ControlCatalog/Pages/DragAndDropPage.xaml

@@ -0,0 +1,19 @@
+<UserControl xmlns="https://github.com/avaloniaui">
+    <StackPanel Orientation="Vertical" Gap="4">
+        <TextBlock Classes="h1">Drag+Drop</TextBlock>
+        <TextBlock Classes="h2">Example of Drag+Drop capabilities</TextBlock>
+
+        <StackPanel Orientation="Horizontal"
+                Margin="0,16,0,0"
+                HorizontalAlignment="Center"
+                Gap="16">
+            <Border BorderBrush="{DynamicResource ThemeAccentBrush}" BorderThickness="2" Padding="16" Name="DragMe">
+                <TextBlock Name="DragState">Drag Me</TextBlock>
+            </Border>
+            <Border Background="{DynamicResource ThemeAccentBrush2}" Padding="16" 
+                    DragDrop.AllowDrop="True">
+                <TextBlock Name="DropState">Drop some text or files here</TextBlock>
+            </Border>
+        </StackPanel>
+    </StackPanel>
+</UserControl>