void IDropTarget.DragOver(UIElement draggedElement, Point mousePosition)
{
ColumnManagerCell cell = draggedElement as ColumnManagerCell;
if (cell != null)
{
HierarchicalGroupByControlNode hierarchicalGroupByControlNode = this.GetHierarchicalGroupByControlNodeFromColumnManagerCell(cell);
// It may not be visible
if (hierarchicalGroupByControlNode != null)
{
hierarchicalGroupByControlNode.ShowFarDropMark(cell, mousePosition);
}
}
else
{
HierarchicalGroupByItem hierarchicalGroupByItem = draggedElement as HierarchicalGroupByItem;
if (hierarchicalGroupByItem == null)
{
return;
}
HierarchicalGroupByControlNode hierarchicalGroupByControlNode = this.GetHierarchicalGroupByControlNodeFromHierarchicalGroupByItem(hierarchicalGroupByItem);
Debug.Assert(hierarchicalGroupByControlNode != null, "CanDrop should have returned false");
if (hierarchicalGroupByControlNode == null)
{
throw new DataGridInternalException("A HierarchicalGroupByControlNode must exist for every level.");
}
hierarchicalGroupByControlNode.ShowFarDropMark(mousePosition);
}
}
void IDropTarget.DragOver(UIElement draggedElement, Point mousePosition)
{
ColumnManagerCell cell = draggedElement as ColumnManagerCell;
if (cell != null)
{
DataGridContext draggedCellDataGridContext = DataGridControl.GetDataGridContext(cell);
HierarchicalGroupByControlNode draggedOverHierarchicalGroupByControlNode = HierarchicalGroupByItem.GetParentHierarchicalGroupByControlNode(this);
if (draggedCellDataGridContext == null)
{
throw new DataGridInternalException("A ColumnManagerCell must have a DataGridContext.");
}
if (draggedOverHierarchicalGroupByControlNode == null)
{
throw new DataGridInternalException("draggedOverHierarchicalGroupByControlNode is null.");
}
if (draggedOverHierarchicalGroupByControlNode.GroupLevelDescriptions == draggedCellDataGridContext.GroupLevelDescriptions)
{
this.ShowDropMark(mousePosition);
}
else
{
// This ColumnManagerCell does not belong this parent HierarchicalGroupByControlNode, display the DropMark on the correct one
HierarchicalGroupByControl parentGBC = GroupingHelper.GetHierarchicalGroupByControl(draggedOverHierarchicalGroupByControlNode);
if (parentGBC == null)
{
throw new DataGridInternalException("The hierarchical group-by item must be rooted by a HierarchicalGroupByControl.");
}
HierarchicalGroupByControlNode hierarchicalGroupByControlNode = parentGBC.GetHierarchicalGroupByControlNodeFromColumnManagerCell(cell);
Debug.Assert(hierarchicalGroupByControlNode != null, "CanDrop should have returned false");
if (hierarchicalGroupByControlNode == null)
{
throw new DataGridInternalException("A HierarchicalGroupByControlNode must exist for every level.");
}
hierarchicalGroupByControlNode.ShowFarDropMark(cell, mousePosition);
}
}
else
{
HierarchicalGroupByItem hierarchicalGroupByItem = draggedElement as HierarchicalGroupByItem;
if (hierarchicalGroupByItem == null)
{
return;
}
HierarchicalGroupByControlNode draggedHierarchicalGroupByControlNode = HierarchicalGroupByItem.GetParentHierarchicalGroupByControlNode(hierarchicalGroupByItem);
HierarchicalGroupByControlNode draggedOverHierarchicalGroupByControlNode = HierarchicalGroupByItem.GetParentHierarchicalGroupByControlNode(this);
if (draggedHierarchicalGroupByControlNode == null)
{
throw new DataGridInternalException("draggedHierarchicalGroupByControlNode is null.");
}
if (draggedOverHierarchicalGroupByControlNode == null)
{
throw new DataGridInternalException("draggedOverHierarchicalGroupByControlNode is null.");
}
if (draggedHierarchicalGroupByControlNode.GroupLevelDescriptions == draggedOverHierarchicalGroupByControlNode.GroupLevelDescriptions)
{
this.ShowDropMark(mousePosition);
}
else
{
// This HierarchicalGroupByItem does not belong this parent HierarchicalGroupByControlNode, display the DropMark on the correct one
HierarchicalGroupByControl parentGBC = GroupingHelper.GetHierarchicalGroupByControl(draggedOverHierarchicalGroupByControlNode);
if (parentGBC == null)
{
throw new DataGridInternalException("A hierarchical group-by item must be rooted by a HierarchicalGroupByControl.");
}
HierarchicalGroupByControlNode hierarchicalGroupByControlNode = parentGBC.GetHierarchicalGroupByControlNodeFromHierarchicalGroupByItem(hierarchicalGroupByItem);
Debug.Assert(hierarchicalGroupByControlNode != null, "CanDrop should have returned false");
if (hierarchicalGroupByControlNode == null)
{
throw new DataGridInternalException("A HierarchicalGroupByControlNode must exist for every level.");
}
hierarchicalGroupByControlNode.ShowFarDropMark(mousePosition);
}
}
}