Xamarin forms 5.0 CollectionView Drag appearence multiple items - xamarin.forms

Question

Good afternoon.
I am using a CollectionView in Xamarin forms 5.0
I already succed to "transfert" 2 or more items from one CollectionView to an other one in the same window using SelectionMode="Multiple".
For my test, i just use and customize a good example founded on the web: https://github.com/CrossGeeks/DragAndDropXFSample
What i'm trying to do concern the appearance of the dragged items.
Because i add a DragGestureRecognizer inside my CollectionView.ItemTemplate.DataTemplate
on my first collection view and a DropGestureRecognizer inside my CollectionView.ItemTemplate.DataTemplate second collection view, the drag & drop functionnality work well.
But, the animation draw only the item i touched, not all the selected ones.
Does anybody has an idea to manage that ?
Is it even possible?
Anyway, thanks for reading and maybe your help ;-)
The xaml page:
<?xml version="1.0" encoding="UTF-8" ?>
<ContentPage
x:Class="DragAndDropXFSample.EventsPage"
xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml">
<ContentPage.Content>
<StackLayout Padding="20,40" BackgroundColor="Black">
<Label
FontAttributes="Bold"
FontSize="Large"
Text="Hi John" />
<Label Text="Your schedule Today" />
<Frame Margin="0,20,0,0" BackgroundColor="White">
<StackLayout>
<CollectionView
x:Name="EventsCollection"
ItemsSource="{Binding Events}"
SelectionMode="Multiple">
<CollectionView.EmptyView>
<Label Text="You have no events" VerticalOptions="CenterAndExpand" />
</CollectionView.EmptyView>
<CollectionView.ItemsLayout>
<GridItemsLayout
HorizontalItemSpacing="10"
Orientation="Vertical"
Span="2"
VerticalItemSpacing="10" />
</CollectionView.ItemsLayout>
<CollectionView.ItemTemplate>
<DataTemplate>
<Frame
Padding="0"
BackgroundColor="{Binding Color}"
HasShadow="False">
<Frame.Style>
<Style TargetType="Frame">
<!-- To visualy show the selection to the user -->
<Setter Property="VisualStateManager.VisualStateGroups">
<VisualStateGroupList>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal" />
<VisualState x:Name="Selected">
<VisualState.Setters>
<Setter Property="BackgroundColor" Value="CadetBlue" />
<Setter TargetName="uiTime" Property="Label.FontAttributes" Value="Italic" />
</VisualState.Setters>
</VisualState>
</VisualStateGroup>
</VisualStateGroupList>
</Setter>
</Style>
</Frame.Style>
<StackLayout Padding="10,10,10,0" Spacing="10">
<Label
x:Name="uiTime"
FontAttributes="Bold"
FontSize="Large"
Text="{Binding Time, StringFormat='{0:HH:mm}'}" />
<Label FontSize="15" Text="{Binding Title}" />
<Label
FontSize="Caption"
Text="{Binding Location, StringFormat='At {0}'}"
TextColor="White" />
<StackLayout
Margin="-10,0"
Padding="5"
BackgroundColor="#66000000"
Orientation="Horizontal">
<Image
HeightRequest="20"
HorizontalOptions="EndAndExpand"
Source="ic_edit" />
<Label
FontSize="Caption"
Text="Edit"
TextColor="White"
VerticalOptions="Center" />
</StackLayout>
</StackLayout>
<Frame.GestureRecognizers>
<DragGestureRecognizer DragStartingCommand="{Binding Path=BindingContext.DragStartingCommand, Source={x:Reference EventsCollection}}" DragStartingCommandParameter="{Binding SelectedItems, Source={x:Reference EventsCollection}}" />
</Frame.GestureRecognizers>
</Frame>
</DataTemplate>
</CollectionView.ItemTemplate>
</CollectionView>
<CollectionView x:Name="EventsCollection2" ItemsSource="{Binding Events2}">
<CollectionView.EmptyView>
<Label Text="You have no events" VerticalOptions="CenterAndExpand" />
</CollectionView.EmptyView>
<CollectionView.ItemsLayout>
<GridItemsLayout
HorizontalItemSpacing="10"
Orientation="Vertical"
Span="2"
VerticalItemSpacing="10" />
</CollectionView.ItemsLayout>
<CollectionView.ItemTemplate>
<DataTemplate>
<Frame
Padding="0"
BackgroundColor="{Binding Color}"
HasShadow="False">
<StackLayout Padding="10,10,10,0" Spacing="10">
<Label
x:Name="uiTime2"
FontAttributes="Bold"
FontSize="Large"
Text="{Binding Time, StringFormat='{0:HH:mm}'}" />
<Label FontSize="15" Text="{Binding Title}" />
<Label
FontSize="Caption"
Text="{Binding Location, StringFormat='At {0}'}"
TextColor="White" />
<StackLayout
Margin="-10,0"
Padding="5"
BackgroundColor="#66000000"
Orientation="Horizontal">
<Image
HeightRequest="20"
HorizontalOptions="EndAndExpand"
Source="ic_edit" />
<Label
FontSize="Caption"
Text="Edit"
TextColor="White"
VerticalOptions="Center" />
</StackLayout>
</StackLayout>
<Frame.GestureRecognizers>
<DropGestureRecognizer DropCommand="{Binding BindingContext.DropOverList2Command, Source={x:Reference EventsCollection2}}" />
</Frame.GestureRecognizers>
</Frame>
</DataTemplate>
</CollectionView.ItemTemplate>
</CollectionView>
</StackLayout>
</Frame>
</StackLayout>
</ContentPage.Content>
</ContentPage>
The view model class :
public class EventsPageViewModel
{
private IList<Event> _dragEvent;
/// <summary>
/// It's a Command<IList<object>> beacause of the Selectionmode.Multiple
/// </summary>
public ICommand DragStartingCommand => new Command<IList<object>>((param) =>
{
_dragEvent = new List<Event>(param.Cast<Event>());
});
public ICommand DropOverList2Command => new Command(() =>
{
foreach (var e in _dragEvent)
{
if (Events.Contains(e))
{
Events.Remove(e);
Events2.Add(e);
}
}
});
public ObservableCollection<Event> Events { get; }
public ObservableCollection<Event> Events2 { get; }
public EventsPageViewModel()
{
Events = new ObservableCollection<Event>()
{
{new Event("Go for a walk", "Home", DateTime.Now.AddHours(3), Color.OrangeRed) },
{new Event("Finish PR", "Work", DateTime.Now.AddHours(5), Color.ForestGreen) },
{new Event("Watch a movie", "Home", DateTime.Now.AddMinutes(40), Color.LightSkyBlue) },
};
Events2 = new ObservableCollection<Event>()
{
{new Event("Go for a walk2", "Home", DateTime.Now.AddHours(3), Color.GreenYellow) }
};
}
}
Edit :
I cannot make video but i 've made some screenshots.
Initial state:
Nothing selected, the top collection view is the source, and the bottom collection view is the dest
I select the first item in the top collection view
I select a second item in the top CollectionView
I start dragging by touching and moving the first selected item
the expected result would be something like :
EDIT:
I find something interresting called Windows.UI.Xaml.DragEventArgs.DragUIOverride
see here but apparently it is for uwp, does anybody know if there is an equivalent for Android/iOS ? Thanks for your time