public static FrameworkElement GetItemContainer(ItemsControl ItemsControl,
Visual BottomMostVisual)
{
FrameworkElement itemContainer = null;
if (ItemsControl != null && BottomMostVisual != null && ItemsControl.Items.Count >= 1)
{
var firstContainer = ItemsControl.ItemContainerGenerator.ContainerFromIndex(0);
if (firstContainer == null)
{
return(itemContainer); // retyrn null;
}
itemContainer = DynamicFormUtilities.FindAncestor(firstContainer.GetType(),
BottomMostVisual);
if (itemContainer == null || itemContainer.DataContext == null)
{
return(itemContainer);
}
var itemContainerVerify = ItemsControl.ItemContainerGenerator.ContainerFromItem(itemContainer.
DataContext) as FrameworkElement;
if (itemContainer != itemContainerVerify)
{
return(null);
}
}
return(itemContainer);
}
private void DropTarget_PreviewDrop(object sender, DragEventArgs e)
{
logger.Trace("Entered DropTarget_PreviewDrop()");
var draggedItem = e.Data.GetData(Format.Name);
var indexRemoved = -1;
if (draggedItem != null)
{
if ((e.Effects & DragDropEffects.Move) != DragDropEffects.None)
{
indexRemoved = DynamicFormUtilities.RemoveItemFromItemsControl(
SourceItemsControl, draggedItem);
}
if (indexRemoved != -1 && SourceItemsControl == TargetItemsControl &&
indexRemoved < InsertionIndex)
{
InsertionIndex--;
}
DynamicFormUtilities.InsertItemInItemsControl(TargetItemsControl,
draggedItem, InsertionIndex);
RemoveDraggedAdorner();
RemoveInsertionAdorner();
}
e.Handled = true;
}
private void DragSource_PreviewMouseLeftButtonDown(object sender,
MouseButtonEventArgs e)
{
var fe = DynamicFormUtilities.GetItemContainer(sender as ItemsControl,
e.OriginalSource as
Visual) as FrameworkElement;
if (fe != null && fe.DataContext is PropertyInformation &&
(fe.DataContext as PropertyInformation
).HasBeenUsed)
{
e.Handled = true;
return;
}
InitialMousePosition = e.GetPosition(TopWindow);
SourceItemsControl = (ItemsControl)sender;
TopWindow = DynamicFormUtilities.FindAncestor(typeof(Window),
SourceItemsControl) as Window;
SourceItemContainer = DynamicFormUtilities.GetItemContainer(
SourceItemsControl, e.OriginalSource
as Visual);
if (SourceItemContainer != null)
{
DraggedData = SourceItemContainer.DataContext;
}
}
private void DragSource_PreviewMouseMove(object sender, MouseEventArgs e)
{
logger.Trace("Entered DragSource_PreviewMouseMove()");
if (DraggedData == null ||
!DynamicFormUtilities.IsMovementBigEnough(InitialMousePosition,
e.GetPosition(TopWindow)))
{
return;
}
var data = new DataObject(Format.Name, DraggedData);
var previousAllowDrop = TopWindow.AllowDrop;
TopWindow.AllowDrop = true;
TopWindow.DragEnter += TopWindow_DragEnter;
TopWindow.DragOver += TopWindow_DragOver;
TopWindow.DragLeave += TopWindow_DragLeave;
var effects = DragDrop.DoDragDrop(sender as DependencyObject, data,
DragDropEffects.Move);
TopWindow.AllowDrop = previousAllowDrop;
TopWindow.DragEnter -= TopWindow_DragEnter;
TopWindow.DragOver -= TopWindow_DragOver;
TopWindow.DragLeave -= TopWindow_DragLeave;
DraggedData = null;
}
private void DecideDropTarget(DragEventArgs e)
{
logger.Trace("Entered DecideDropTarget()");
var targetItemsControlCount = TargetItemsControl.Items.Count;
var draggedItem = e.Data.GetData(Format.Name);
if (IsDropDataTypeAllowed(draggedItem))
{
if (targetItemsControlCount > 0)
{
HasVerticalOrientation = DynamicFormUtilities.HasVerticalOrientation(
TargetItemsControl.
ItemContainerGenerator.ContainerFromIndex(0) as FrameworkElement);
TargetItemContainer = DynamicFormUtilities.GetItemContainer(
TargetItemsControl, e.
OriginalSource as Visual);
if (TargetItemContainer != null)
{
IsInFirstHalf = DynamicFormUtilities.IsInFirstHalf(TargetItemContainer,
e.GetPosition(TargetItemContainer),
HasVerticalOrientation);
InsertionIndex =
TargetItemsControl.ItemContainerGenerator.IndexFromContainer(
TargetItemContainer);
if (!IsInFirstHalf)
{
InsertionIndex++;
}
}
else
{
TargetItemContainer =
TargetItemsControl.ItemContainerGenerator.ContainerFromIndex(
targetItemsControlCount - 1) as FrameworkElement;
IsInFirstHalf = false;
InsertionIndex = targetItemsControlCount;
}
}
else
{
TargetItemContainer = null;
InsertionIndex = 0;
}
}
else
{
TargetItemContainer = null;
InsertionIndex = -1;
e.Effects = DragDropEffects.None;
}
}