private void ClearDragFeedback()
{
if (_dragFeedback != null)
{
_dragFeedback.Dispose();
_dragFeedback = null;
}
}
private void ResolveDragFeedback()
{
ClearDragFeedback();
// Start with the provided value
PaletteDragFeedback dragFeedback = _stateCommon.GetDragDropFeedback();
// Should never be 'inherit'
if (dragFeedback == PaletteDragFeedback.Inherit)
{
dragFeedback = PaletteDragFeedback.Rounded;
}
// Check if the rounded style is possible
if (dragFeedback == PaletteDragFeedback.Rounded)
{
// Rounded feedback uses a per-pixel alpha blending and so we need to be on a machine that supports
// more than 256 colors and also allows the layered windows feature. If not then revert to sqaures
if ((OSFeature.Feature.GetVersionPresent(OSFeature.LayeredWindows) == null) || (CommonHelper.ColorDepth() <= 8))
{
dragFeedback = PaletteDragFeedback.Square;
}
}
switch (dragFeedback)
{
case PaletteDragFeedback.Rounded:
case PaletteDragFeedback.Square:
_dragFeedback = new DragFeedbackDocking(dragFeedback);
break;
default:
_dragFeedback = new DragFeedbackSolid();
break;
}
}