void SetItemsInViewModelColumns(ObservableCollection <ColumnViewModel> columns)
{
Dictionary <object, ColumnViewModel> quickColumnsFromId = new Dictionary <object, ColumnViewModel>();
Dictionary <object, IEnumerable <ItemViewModel> > listFromId = new Dictionary <object, IEnumerable <ItemViewModel> >();
ObservableCollection <ItemViewModel> remainingItems = new ObservableCollection <ItemViewModel>();
ColumnViewModel unclassifiedColumn = null;
foreach (ColumnViewModel column in columns)
{
column.UnalteredItemsCollection.Clear();
if (column.ColumnDefinition.Id != null)
{
quickColumnsFromId.Add(column.ColumnDefinition.Id, column);
listFromId.Add(column.ColumnDefinition.Id, new ObservableCollection <ItemViewModel>());
}
else
{
unclassifiedColumn = column;
unclassifiedColumn.IsUnclassifiedColumn = true;
}
}
if (ItemsSource != null)
{
foreach (Object item in ItemsSource)
{
//Get the id from the item and add a Binding to it so we can update it when necessary:
object id;
ItemViewModel itemViewModel = new ItemViewModel(item, this);
Binding binding = new Binding(ColumnMemberPath);
binding.Source = item;
binding.Mode = BindingMode.TwoWay;
BindingOperations.SetBinding(itemViewModel, ItemViewModel.ItemColumnIdProperty, binding);
//itemViewModel.SetBinding(ItemViewModel.ItemColumnIdProperty, binding);
id = itemViewModel.ItemColumnId;
//todo: handle the case where the Binding is broken.
//Add a binging to get the ItemOrder:
Binding orderBinding = new Binding(OrderMemberPath);
orderBinding.Source = item;
orderBinding.Mode = BindingMode.TwoWay;
BindingOperations.SetBinding(itemViewModel, ItemViewModel.ItemOrderProperty, orderBinding);
//itemViewModel.SetBinding(ItemViewModel.ItemOrderProperty, orderBinding);
//Add the item to the list for the corresponding id:
if (id != null && listFromId.ContainsKey(id))
{
((ObservableCollection <ItemViewModel>)listFromId[id]).Add(itemViewModel);
}
else
{
remainingItems.Add(itemViewModel);
}
}
foreach (object id in listFromId.Keys)
{
quickColumnsFromId[id].UnalteredItemsCollection = (ObservableCollection <ItemViewModel>)listFromId[id];
}
if (unclassifiedColumn != null)
{
//we should always enter this "if"
unclassifiedColumn.UnalteredItemsCollection = remainingItems;
}
}
}
public void Execute(object parameter)
{
//Version using Drop event:
var param = parameter as System.Windows.DragEventArgs;
if (param != null)
{
var castedParameter = param.Data.GetData("ItemDragEventArgs") as ItemDragEventArgs;
int newItemOrder = -1;
//We get the item on which the element was dropped:
var elements = VisualTreeHelper.FindElementsInHostCoordinates(param.GetPosition(null).Position, _column.ColumnDefinition._kanBanControl);
FrameworkElement elementDroppedOn = elements.ElementAt(0) as FrameworkElement;
while (elementDroppedOn != null && //we go up the visual tree until we reached the root or...
(elementDroppedOn.DataContext == null || elementDroppedOn.DataContext.GetType() != typeof(ItemViewModel))) //...until we found an element that has the ItemViewModel as DataContext
{
elementDroppedOn = elementDroppedOn.Parent as FrameworkElement;
}
if (elementDroppedOn != null)
{
//todo: find a way to know in which half of the DropElement the dragged element was dropped.
// We could do with comparing the position at which it was dropped with the position of the root of the item card
// (but it need us to find said root - could be done by going up the visual tree until we find an element whose DataContext is not an ItemViewModel
// -> the last one with the ItemViewModel should be the root element)
// We could try to know it the cursor was on the Header or the body of the card.
//for now, we will consider the element dropped above:
newItemOrder = ((ItemViewModel)elementDroppedOn.DataContext).ItemOrder + 1; //Reminder: we have chosen to have the items with the bigger order number higher on the displayed list.
}
//Version using ItemDragCompleted event (this one doesn't seem good because the sender is the column from which the item comes):
//var castedParameter = parameter as ItemDragEventArgs;
//if(castedParameter != null)
//{
SelectionCollection selectionCollection = castedParameter.Data as SelectionCollection;
if (selectionCollection.Count > 0)
{
Selection selection = selectionCollection.ElementAt(0); //we can only drag one item so it is at the position 0.
FrameworkElement container = selection.Item as FrameworkElement;
ItemViewModel itemViewModel = container.DataContext as ItemViewModel;
if (itemViewModel != null)
{
itemViewModel.ItemOrder = newItemOrder;
UpdateItemOrders(newItemOrder);
itemViewModel.ItemColumnId = _column.ColumnDefinition.Id;
//force a refresh of the KanBanControl:
//todo: find a way to only refresh the Column itself.
var kanBanControl = _column.ColumnDefinition._kanBanControl;
var columns = kanBanControl.Columns;
kanBanControl.Columns = null;
kanBanControl.Columns = columns;
// Raise the "ItemMoved" event:
kanBanControl.OnItemMoved(itemViewModel);
//keep the following to only refresh the column itself. It cannot be used properly currently as it causes a bug where the items are duplicated.
////refresh the elements of the column:
//_column.Dispatcher.BeginInvoke( () =>
//{
// _column.UnalteredItemsCollection.Add(itemViewModel); //we add the item manually because the whole collection was not refreshed in the process. This should change with Smooth refresh.
// _column.SetOrderedItemsCollection();
// });
//_column.SetOrderedItemsCollection();
}
}
}
}