public static void AdornDropTarget(DropInfo dropInfo)
{
if (dropInfo == null) throw new ArgumentNullException("dropInfo");
if (dropInfo.Type == DataSourceDropType.None)
throw new ArgumentException("dropInfo.DropType may not be set to none");
if (dropInfo.Type.HasFlag(DataSourceDropType.Group))
{
if (dropInfo.TargetGroup == null)
throw new ArgumentException("dropInfo.Group is set to null but the type is set to group");
AddDropAdorner(dropInfo.TargetGroup.TreeViewItem);
}
else
{
RemoveDropAdorner();
}
if (dropInfo.Type.HasFlag(DataSourceDropType.ArrangeTop) ||
dropInfo.Type.HasFlag(DataSourceDropType.ArrangeBottom))
{
AddArrangeAdorner(dropInfo.Target.TreeViewItem, dropInfo.Type);
}
else
{
RemoveArrangeAdorner();
}
}
private bool IsValidDrop(DragEventArgs e, out DropInfo dropInfo)
{
dropInfo = null;
IDataSourceViewModel viewModel = e.Data.GetData(typeof (SingleDataSourceViewModel)) as IDataSourceViewModel ??
e.Data.GetData(typeof (MergedDataSourceViewModel)) as IDataSourceViewModel;
var source = new TreeItem
{
ViewModel = viewModel
};
if (source.ViewModel == null)
return false;
TreeItem dropTarget = GetDataSourceFromPosition(e.GetPosition(_partDataSources));
if (dropTarget == null)
return false;
DataSourceDropType dropType = GetDropType(e, dropTarget, viewModel);
var model = (MainWindowViewModel) DataContext;
IDataSourceViewModel group;
if (!model.CanBeDropped(source.ViewModel, dropTarget.ViewModel, dropType, out group))
return false;
dropInfo = new DropInfo
{
Source = source,
Type = dropType,
Target = dropTarget,
TargetGroup = new TreeItem
{
ViewModel = group,
TreeViewItem = GetTreeViewItem(group)
}
};
return true;
}