/// <summary>
/// Undo the last entity change
/// </summary>
public void Undo()
{
_IsInUndoRedoOperation = true;
if (UndoList.Count > 0)
{
// Extract the item from the undo list.
int undoActionId = UndoList.Last().ActionId;
UndoRedoEntityInfo <TEntity> item;
for (int i = UndoList.Count - 1; i >= 0; i--)
{
item = UndoList.Last();
if (item.ActionId == undoActionId)
{
UndoList.RemoveAt(UndoList.Count - 1);
List <UndoRedoEntityInfo <TEntity> > copyRedoList = RedoList.ToList();
copyRedoList.Add(item);
// We need to copy the undo list here.
List <UndoRedoEntityInfo <TEntity> > copyUndoList = UndoList.ToList();
FuncUndo(item);
// Now repopulate the undo and redo lists.
UpdateRedoList(copyRedoList);
UndoList.Clear();
UndoList.AddRange(copyUndoList);
}
}
SetActionId(_ActionId - 1);
}
_IsInUndoRedoOperation = false;
}
/// <summary>
/// Redo the last undone entity change
/// </summary>
/// <remarks>
/// Unlike the undo operation, we don't need to copy the undo list out
/// because we want the item we're redoing being added back to the redo
/// list.
/// </remarks>
public void Redo()
{
_IsInUndoRedoOperation = true;
if (RedoList.Count > 0)
{
// Extract the item from the redo list.
int redoActionId = RedoList.Last().ActionId;
UndoRedoEntityInfo <TEntity> item;
for (int i = RedoList.Count - 1; i >= 0; i--)
{
item = RedoList.Last();
if (item.ActionId == redoActionId)
{
// Now, remove it from the list.
RedoList.RemoveAt(RedoList.Count - 1);
// Here we need to copy the redo list out because
// we will clear the list when the Add is called and
// the Redo is cleared there.
List <UndoRedoEntityInfo <TEntity> > redoList = RedoList.ToList();
//Redo actionId should be the same as undo action id
SetActionId(item.ActionId);
// Redo the last operation.
FuncRedo(item);
// Add the last redo item into undo list
AddUndo(item.ChangedEntity, item.PropertyName, item.OldValue, item.NewValue, item.MessageType);
// Now reset the redo list.
UpdateRedoList(redoList);
}
}
}
_IsInUndoRedoOperation = false;
}
public void Redo()
{
if (RedoList.Count > 0)
{
IUndoRedo item = RedoList.First();
RedoList.RemoveFirst();
LinkedList <IUndoRedo> cpyRedo = new LinkedList <IUndoRedo>(RedoList.ToList());
item.Redo();
RedoList = new LinkedList <IUndoRedo>(cpyRedo);
RaisePropertyChanged("RedoDescription");
RaisePropertyChanged("UndoDescription");
}
}
