C＃UWP-如何获取对象的拖动图像？

Question

How can I get a copy of the drag image for an item I'm dragging in my application?

The DragStarting event contains a DragStartingEventArgs object that includes a DragUI object whose description is, " The visual representation of the data being dragged. " Ideally, I'd like to do something like this within the DragStarting event:

    private void OnDragStarting( UIElement sender, DragStartingEventArgs args )
    {
        // Create a new bitmap image object
        var dragImage = new BitmapImage();

        // Assign the drag image to the new bitmap image object
        dragImage = args.DragUI. ????
    }

However, there doesn't seem to be a way to get the drag image from the DragUI object. DragUI contains only "Set*" methods, and no "Get*" methods.

Is there a way to get the drag image as the drag operation begins?

Answer 1

You can use DataView.GetStorageItemsAsync() to receive the items you dragged into your applications.

<Grid AllowDrop="True" DragOver="Image_drop_drag_over_ui" Drop="image_drop"/>

//C# code

public async void Image_Drop(object sender, DragEventArgs e)
{
     if (e.DataView.Contains(StandardDataFormats.StorageItems))
     {
        List<StorageFile> received_images = new List<StorageFile>();
        var items = await e.DataView.GetStorageItemsAsync();
        var storageFile = items[0] as StorageFile;
        received_images.Add(storageFile);
     }
}
private void Image_drop_drag_over_ui(object sender, DragEventArgs e)
{
     e.AcceptedOperation = DataPackageOperation.Copy;
     e.DragUIOverride.Caption = "Drop receipt";
     e.DragUIOverride.IsCaptionVisible = true; 
}