Enable requesting the full preview size on iOS drag shadow & iOS and Windows Samples

src/Controls/samples/Controls.Sample/Pages/PlatformSpecifics/Windows/WindowsDragAndDropCustomization.xaml

@@ -0,0 +1,65 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ContentPage
+    xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
+    xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
+    x:Class="Maui.Controls.Sample.Pages.WindowsDragAndDropCustomization"
+    Title="Drag and Drop Windows Platform-Specific">
+    <Grid Margin="20" RowDefinitions="290,*">
+
+        <Border Margin="15" Grid.Row="0">
+            <StackLayout>
+                <Label Text="Drag and Drop the items below" FontSize="Large" FontAttributes="Bold"/>
+                <CollectionView x:Name="CollectionView1">
+                    <CollectionView.ItemTemplate>
+                        <DataTemplate>
+                                <Label Text="{Binding Name}" Background="LightGray" HeightRequest="30" HorizontalOptions="Fill" Margin="3">
+                                    <Label.GestureRecognizers>
+                                        <DragGestureRecognizer />
+                                    </Label.GestureRecognizers>
+                                </Label>
+                        </DataTemplate>
+                    </CollectionView.ItemTemplate>
+                </CollectionView>
+            </StackLayout>
+        </Border>
+
+        <TableView Intent="Settings" Grid.Row="1" >
+            <TableRoot>
+                <TableSection Title="Drag Customization">
+
+                    <ViewCell>
+                        <Grid ColumnDefinitions="3*,*" VerticalOptions="Center" Margin="10,0,5,0">
+                            <Label Text="Show Glyph" VerticalTextAlignment="Center" Grid.Column="0"/>
+                            <Switch HorizontalOptions="End" x:Name="ShowGlyphSwitch" IsToggled="True" Grid.Column="1"/>
+                        </Grid>
+                    </ViewCell>
+
+                    <ViewCell>
+                        <Grid ColumnDefinitions="3*,*" VerticalOptions="Center" Margin="10,0,5,0">
+                            <Label Text="Custom Caption" VerticalTextAlignment="Center" Grid.Column="0"/>
+                            <Entry HorizontalOptions="End" WidthRequest="300" Placeholder="Copy" x:Name="CustomCaptionEntry" Grid.Column="1"/>
+                        </Grid>
+                    </ViewCell>
+
+                    <ViewCell>
+                        <Grid ColumnDefinitions="3*,*" VerticalOptions="Center" Margin="10,0,5,0">
+                            <Label Text="Show Caption" VerticalTextAlignment="Center" Grid.Column="0"/>
+                            <Switch HorizontalOptions="End" x:Name="ShowCaptionSwitch" IsToggled="True" Grid.Column="1"/>
+                        </Grid>
+                    </ViewCell>
+
+                    <ViewCell>
+                        <Grid ColumnDefinitions="3*,*" VerticalOptions="Center" Margin="10,0,5,0">
+                            <Label Text="Show Content" VerticalTextAlignment="Center" Grid.Column="0"/>
+                            <Switch HorizontalOptions="End" x:Name="ShowContentSwitch" Grid.Column="1" IsToggled="True"/>
+                        </Grid>
+                    </ViewCell>
+                </TableSection>
+
+            </TableRoot>
+        </TableView>
+        <Grid.GestureRecognizers>
+            <DropGestureRecognizer DragOver="DropGestureRecognizer_DragOver" />
+        </Grid.GestureRecognizers>
+    </Grid>
+</ContentPage>

src/Controls/samples/Controls.Sample/Pages/PlatformSpecifics/Windows/WindowsDragAndDropCustomization.xaml.cs

@@ -0,0 +1,48 @@
+using System;
+using Maui.Controls.Sample.ViewModels;
+using Microsoft.Maui.Controls;
+using Microsoft.Maui.Controls.PlatformConfiguration;
+using Microsoft.Maui.Controls.PlatformConfiguration.WindowsSpecific;
+
+namespace Maui.Controls.Sample.Pages
+{
+	public partial class WindowsDragAndDropCustomization : ContentPage
+	{
+		public WindowsDragAndDropCustomization()
+		{
+			InitializeComponent();
+
+			CollectionView1.ItemsSource = new NameObject[]
+			{
+				new NameObject ("First Item"),
+				new NameObject ("Second Item"),
+				new NameObject ("Third Item"),
+				new NameObject ("Fourth Item"),
+				new NameObject ("Fifth Item"),
+				new NameObject ("Sixth Item"),
+			};
+		}
+
+		void DropGestureRecognizer_DragOver(System.Object sender, Microsoft.Maui.Controls.DragEventArgs e)
+		{
+#if WINDOWS
+			var dragUI = e.PlatformArgs.DragEventArgs.DragUIOverride;
+			dragUI.IsCaptionVisible = ShowCaptionSwitch.IsToggled;
+			dragUI.IsGlyphVisible = ShowGlyphSwitch.IsToggled;
+			dragUI.IsContentVisible = ShowContentSwitch.IsToggled;
+
+			dragUI.Caption = string.IsNullOrEmpty (CustomCaptionEntry.Text) ? "Copy" : CustomCaptionEntry.Text;
+#endif
+		}
+
+		public class NameObject
+		{
+			public NameObject(string name)
+			{
+				Name = name;
+			}
+
+			public string Name { get; set; }
+		}
+	}
+}

src/Controls/samples/Controls.Sample/Pages/PlatformSpecifics/iOS/iOSDragAndDropRequestFullSize.xaml

@@ -0,0 +1,79 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ContentPage 
+    xmlns="http://schemas.microsoft.com/dotnet/2021/maui" 
+    xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"            
+    x:Class="Maui.Controls.Sample.Pages.iOSDragAndDropRequestFullSize"
+    Title="Drag and Drop iOS Platform-Specific">
+    <Grid Margin="20" RowDefinitions="300,*">
+
+        <Border Margin="15" Grid.Row="0">
+            <StackLayout>
+                <Label Text="Drag and Drop the items below" FontSize="Large" FontAttributes="Bold"/>
+                <CollectionView x:Name="CollectionView1">
+                    <CollectionView.ItemTemplate>
+                        <DataTemplate>
+                            <Entry Text="{Binding Name}">
+                                <Entry.GestureRecognizers>
+                                    <DragGestureRecognizer DragStarting="DragGestureRecognizer_DragStarting" />
+                                    <DropGestureRecognizer DragOver="DropGestureRecognizer_DragOver" />
+                                </Entry.GestureRecognizers>
+                            </Entry>
+                        </DataTemplate>
+                    </CollectionView.ItemTemplate>
+                </CollectionView>
+            </StackLayout>
+        </Border>
+
+        <TableView Intent="Settings" Grid.Row="1" >
+            <TableRoot>
+                <TableSection Title="Drag size option">
+                    <ViewCell>
+                        <Grid ColumnDefinitions="3*,*" VerticalOptions="Center" Margin="10,0,5,0">
+                            <Label Text="Request Full-Sized Drag Previews" VerticalTextAlignment="Center" Grid.Column="0"/>
+                            <Switch HorizontalOptions="End" x:Name="fullSizedSwitch" Toggled="FullSized_Switch_Toggled" Grid.Column="1"/>
+                        </Grid>
+                    </ViewCell>
+                </TableSection>
+
+                <TableSection Title="Content Options">
+                    <ViewCell>
+                        <Grid ColumnDefinitions="3*,*" VerticalOptions="Center" Margin="10,0,5,0">
+                            <Label Text="Use drawn image" VerticalTextAlignment="Center" Grid.Column="0"/>
+                            <Switch HorizontalOptions="End" x:Name="drawnImageSwitch" Toggled="Drawn_Switch_Toggled" Grid.Column="1"/>
+                        </Grid>
+                    </ViewCell>
+
+                    <ViewCell>
+                        <Grid ColumnDefinitions="3*,*"  VerticalOptions="Center" Margin="10,0,5,0">
+                            <Label Text="Use dotnet bot image" VerticalTextAlignment="Center" Grid.Column="0"/>
+                            <Switch HorizontalOptions="End" x:Name="dotnetBotImageSwitch" Toggled="DotnetBot_Switch_Toggled" Grid.Column="1"/>
+                        </Grid>
+                    </ViewCell>
+                </TableSection>
+                    <TableSection Title="Drop Types">
+                    <ViewCell>
+                        <Grid ColumnDefinitions="3*,*" VerticalOptions="Center" Margin="10,0,5,0">
+                            <Label Text="UIDropProposal - Copy" VerticalTextAlignment="Center" Grid.Column="0"/>
+                            <Switch HorizontalOptions="End" x:Name="copySwitch" IsToggled="True" Toggled="Copy_Switch_Toggled" Grid.Column="1"/>
+                        </Grid>
+                    </ViewCell>
+
+                    <ViewCell>
+                        <Grid ColumnDefinitions="3*,*" VerticalOptions="Center" Margin="10,0,5,0">
+                            <Label Text="UIDropProposal - Move" VerticalTextAlignment="Center" Grid.Column="0"/>
+                            <Switch HorizontalOptions="End" x:Name="moveSwitch" Toggled="Move_Switch_Toggled" Grid.Column="1"/>
+                        </Grid>
+                    </ViewCell>
+
+                    <ViewCell>
+                        <Grid ColumnDefinitions="3*,*" VerticalOptions="Center" Margin="10,0,5,0">
+                            <Label Text="UIDropProposal - Forbidden" VerticalTextAlignment="Center" Grid.Column="0"/>
+                            <Switch HorizontalOptions="End" x:Name="forbiddenSwitch" Toggled="Forbidden_Switch_Toggled" Grid.Column="1"/>
+                        </Grid>
+                    </ViewCell>
+
+                </TableSection>
+            </TableRoot>
+        </TableView>
+    </Grid>
+</ContentPage>

src/Controls/samples/Controls.Sample/Pages/PlatformSpecifics/iOS/iOSDragAndDropRequestFullSize.xaml.cs

@@ -0,0 +1,145 @@
+using System;
+using Maui.Controls.Sample.ViewModels;
+using Microsoft.Maui.Controls;
+using Microsoft.Maui.Controls.PlatformConfiguration;
+using Microsoft.Maui.Controls.PlatformConfiguration.iOSSpecific;
+
+namespace Maui.Controls.Sample.Pages
+{
+	public partial class iOSDragAndDropRequestFullSize : ContentPage
+	{
+		public iOSDragAndDropRequestFullSize()
+		{
+			InitializeComponent();
+
+			CollectionView1.ItemsSource = new NameObject[]
+			{
+				new NameObject ("First Item"),
+				new NameObject ("Second Item"),
+				new NameObject ("Third Item"),
+				new NameObject ("Fourth Item"),
+				new NameObject ("Fifth Item"),
+				new NameObject ("Sixth Item"),
+			};
+
+			// Changing the drag preview is not observed working the same as in iOS
+#if MACCATALYST
+			fullSizedSwitch.IsEnabled = false;
+			drawnImageSwitch.IsEnabled = false;
+			dotnetBotImageSwitch.IsEnabled = false;
+#endif
+		}
+
+		void DragGestureRecognizer_DragStarting(System.Object sender, Microsoft.Maui.Controls.DragStartingEventArgs e)
+		{
+#if IOS || MACCATALYST
+			if (drawnImageSwitch.IsToggled)
+			{
+				Func<UIKit.UIDragPreview> action = () =>
+				{
+					var previewParameters = new UIKit.UIDragPreviewParameters();
+					var funkyPath = new UIKit.UIBezierPath();
+					funkyPath.MoveTo(new CoreGraphics.CGPoint(0, 0));
+					funkyPath.AddLineTo(new CoreGraphics.CGPoint(300, 0));
+					funkyPath.AddLineTo(new CoreGraphics.CGPoint(225, 150));
+					funkyPath.AddLineTo(new CoreGraphics.CGPoint(300, 300));
+					funkyPath.AddLineTo(new CoreGraphics.CGPoint(0, 300));
+					funkyPath.ClosePath();
+					previewParameters.VisiblePath = funkyPath;
+
+					return new UIKit.UIDragPreview(e.PlatformArgs.Sender, previewParameters);
+				};
+
+				e.PlatformArgs.SetPreviewProvider(action);
+			}
+
+			else if (dotnetBotImageSwitch.IsToggled)
+			{
+				Func<UIKit.UIDragPreview> action = () =>
+				{
+					var image = UIKit.UIImage.FromFile("dotnet_bot.png");
+
+					UIKit.UIImageView imageView = new UIKit.UIImageView(image);
+					imageView.ContentMode = UIKit.UIViewContentMode.Center;
+					imageView.Frame = new CoreGraphics.CGRect(0, 0, 250, 250);
+
+					return new UIKit.UIDragPreview(imageView);
+				};
+
+				e.PlatformArgs.SetPreviewProvider(action);
+			}
+
+
+			e.PlatformArgs.SetPrefersFullSizePreviews((interaction, session) => { return fullSizedSwitch.IsToggled; });
+#endif
+		}
+
+		void Drawn_Switch_Toggled(object sender, ToggledEventArgs e)
+		{
+			if (e.Value)
+				dotnetBotImageSwitch.IsToggled = false;
+		}
+
+		void DotnetBot_Switch_Toggled(object sender, ToggledEventArgs e)
+		{
+			if (e.Value)
+				drawnImageSwitch.IsToggled = false;
+		}
+
+		void DropGestureRecognizer_DragOver(System.Object sender, Microsoft.Maui.Controls.DragEventArgs e)
+		{
+#if IOS || MACCATALYST
+			if (copySwitch.IsToggled)
+				e.PlatformArgs.SetDropProposal(new UIKit.UIDropProposal(UIKit.UIDropOperation.Copy));
+			else if (moveSwitch.IsToggled)
+				e.PlatformArgs.SetDropProposal(new UIKit.UIDropProposal(UIKit.UIDropOperation.Move));
+			else if (forbiddenSwitch.IsToggled)
+				e.PlatformArgs.SetDropProposal(new UIKit.UIDropProposal(UIKit.UIDropOperation.Forbidden));
+#endif
+		}
+
+		void FullSized_Switch_Toggled(object sender, ToggledEventArgs e)
+		{
+		}
+
+		void Copy_Switch_Toggled(object sender, ToggledEventArgs e)
+		{
+			if (e.Value)
+			{
+				moveSwitch.IsToggled = false;
+				forbiddenSwitch.IsToggled = false;
+			}
+		}
+
+		void Move_Switch_Toggled(object sender, ToggledEventArgs e)
+		{
+			if (e.Value)
+			{
+				copySwitch.IsToggled = false;
+				forbiddenSwitch.IsToggled = false;
+			}
+		}
+
+		void Forbidden_Switch_Toggled(object sender, ToggledEventArgs e)
+		{
+			if (e.Value)
+			{
+				moveSwitch.IsToggled = false;
+				copySwitch.IsToggled = false;
+			}
+		}
+
+		public class NameObject
+		{
+			public NameObject(string name)
+			{
+				Name = name;
+			}
+
+			public string Name { get; set; }
+		}
+	}
+
+
+
+}

src/Controls/samples/Controls.Sample/ViewModels/PlatformSpecificsViewModel.cs

@@ -60,6 +60,9 @@ protected override IEnumerable<SectionModel> CreateItems()
 				new SectionModel(typeof(iOSFlyoutPage), "FlyoutPage Shadow",
 					"This platform-specific controls whether the detail page of a FlyoutPage has shadow applied to it, when revealing the flyout page."),
 
+				new SectionModel(typeof(iOSDragAndDropRequestFullSize), "Drag and Drop Gesture Recognizer Platform-Specific",
+					"This iOS platform-specific controls whether to request full-sized drag shadows and the UIDropProposal types."),
+
 				new SectionModel(typeof(iOSHideHomeIndicatorPage), "Hide Home Indicator",
 					"This iOS platform-specific sets the visibility of the home indicator on a Page."),
 
@@ -123,6 +126,9 @@ protected override IEnumerable<SectionModel> CreateItems()
 				new SectionModel(typeof(WindowsCollapseWidthAdjusterPage), "FlyoutPage Navigation Bar",
 					"This WinUI platform-specific is used to collapse the navigation bar on a FlyoutPage."),
 
+				new SectionModel(typeof(WindowsDragAndDropCustomization), "Drag and Drop Gesture Recognizer Platform-Specific",
+					"This WinUI platform-specific displays drag and drop customization such as custom drag gylph and text."),
+
 				new SectionModel(typeof(WindowsListViewPage), "ListView Selection Mode",
 					"This WinUI platform-specific controls whether items in a ListView can respond to tap gestures, and hence whether the native ListView fires the ItemClick or Tapped event."),
 

src/Controls/src/Core/DragAndDrop/PlatformDragStartingEventArgs.cs

@@ -26,6 +26,7 @@ public class PlatformDragStartingEventArgs
 	internal Foundation.NSItemProvider? ItemProvider { get; private set; }
 	internal Func<UIKit.UIDragPreview?>? PreviewProvider { get; private set; }
 	internal UIKit.UIDragItem[]? DragItems { get; private set; }
+	internal Func<UIKit.UIDragInteraction, UIKit.IUIDragSession, bool>? PrefersFullSizePreviews { get; private set; }
 
 	internal PlatformDragStartingEventArgs(UIKit.UIView? sender, UIKit.UIDragInteraction dragInteraction,
 		UIKit.IUIDragSession dragSession)
@@ -71,6 +72,21 @@ public void SetDragItems(UIKit.UIDragItem[] dragItems)
 		DragItems = dragItems;
 	}
 
+	/// <summary>
+	/// Sets the func that requests to keep drag previews full-sized when dragging begins.
+	/// </summary>
+	/// <param name="prefersFullSizePreviews">Func that returns whether to request full size previews.</param>
+	/// <remarks>
+	/// The default behavior on iOS is to reduce the size of the drag shadow if not requested here.
+	/// Even if requested, it is up to the system whether or not to fulfill the request.
+	/// This method exists inside <see cref="PlatformDragStartingEventArgs"/> since the preview must
+	/// have this value set when dragging begins.
+	/// </remarks>
+	public void SetPrefersFullSizePreviews(Func<UIKit.UIDragInteraction, UIKit.IUIDragSession, bool>? prefersFullSizePreviews)
+	{
+		PrefersFullSizePreviews = prefersFullSizePreviews;
+	}
+
 #elif ANDROID
 	/// <summary>
 	/// Gets the native view attached to the event.