private void Drag(IDataSourceViewModel source, IDataSourceViewModel dest)
{
var merged = dest as MergedDataSourceViewModel;
if (merged != null)
{
// Drag from ungrouped onto an existing group
// => add to existing group
AddFileToGroup(source, merged);
}
else
{
// Drag from ungrouped onto a dest within a group
// => find group of dest and addd to it
merged = dest.Parent as MergedDataSourceViewModel;
if (merged != null)
{
AddFileToGroup(source, merged);
}
else
{
// Drag from ungrouped onto another ungrouped source
// => remove dest as well and create new group
int destIndex = _observable.IndexOf(dest);
if (destIndex != -1)
{
_observable.Remove(dest);
MergedDataSource mergedDataSource = _dataSources.AddGroup();
merged = new MergedDataSourceViewModel(mergedDataSource);
merged.Remove += OnRemove;
merged.AddChild(source);
merged.AddChild(dest);
_observable.Insert(destIndex, merged);
SelectedItem = merged;
}
}
}
}
private static void AddFileToGroup(IDataSourceViewModel source, MergedDataSourceViewModel viewModel)
{
viewModel.AddChild(source);
}