//When the user enters a drop target with a dragged image, the image is dropped in the appropriate location
private void OnDropTargetDragEnter(object sender, SurfaceDragDropEventArgs e)
{
PhotoData data = e.Cursor.Data as PhotoData;
if (!data.CanDrop)
{
e.Effects = DragDropEffects.Move;
}
}
// When the user initializes drag and drop functions, the cursor changes to reflect selected image
private void Scatter_PreviewTouchDown(object sender, TouchEventArgs e)
{
FrameworkElement findSource = e.OriginalSource as FrameworkElement;
ScatterViewItem draggedElement = null;
//find the ScatterViewItem object that is being touched
while (draggedElement == null && findSource != null)
{
if ((draggedElement = findSource as ScatterViewItem) == null)
{
findSource = VisualTreeHelper.GetParent(findSource) as FrameworkElement;
}
}
if (draggedElement == null)
{
return;
}
PhotoData data = draggedElement.Content as PhotoData;
ContentControl cursorVisual = new ContentControl()
{
Content = draggedElement.DataContext,
Style = FindResource("CursorStyle") as Style
};
//create the list of input devices and the feducial markers
//add the touches that are currently captured within the dragged elt and
//the current touch (if it isn't already in the list)
List <InputDevice> devices = new List <InputDevice>();
devices.Add(e.TouchDevice);
foreach (TouchDevice touch in draggedElement.TouchesCapturedWithin)
{
if (touch != e.TouchDevice)
{
devices.Add(touch);
}
}
//get the drag source object
ItemsControl dragSource = ItemsControl.ItemsControlFromItemContainer(draggedElement);
//the scatterview object that the cursor is dragged out from
SurfaceDragDrop.BeginDragDrop(
dragSource, //the scatterview object that the cursor is dragged out from
draggedElement, //the ScatterViewItem object that is dragged from the drag source
cursorVisual, //the visual element of the cursor
draggedElement.DataContext, //the data attached with the cursor
devices, //the input devices that start dragging the cursor
DragDropEffects.None); //the allowed drag-and-drop
//this prevents the default touch operator from happening
e.Handled = true;
//hide the scatterviewitem for now. we will remove it if the dragdrop is successful
draggedElement.Visibility = Visibility.Hidden;
}
// When the user drops a dragged item into the drop target, the cursor image changes from that image to default cursor
private void OnTargetChanged(object sender, TargetChangedEventArgs e)
{
if (e.Cursor.CurrentTarget != null)
{
PhotoData data = e.Cursor.Data as PhotoData;
e.Cursor.Visual.Tag = (data.CanDrop) ? "CanDrop" : "CannotDrop";
}
else
{
e.Cursor.Visual.Tag = null;
}
}
