/// <summary>
/// Performs an undo
/// </summary>
/// <returns>False if there weren't any undos, true otherwise</returns>
public bool Undo()
{
if (!this.AnyUndos)
{
return(false);
}
bool anyUndosChange = m_undoStack.Count == 1;
bool anyRedosChange = m_redoStack.Count == 0;
IUndoableAction action = m_undoStack[0];
m_undoStack.RemoveAt(0);
action.Undo();
m_redoStack.Insert(0, action);
if (anyUndosChange)
{
this.RaisePropertiesChanged(nameof(AnyUndos));
}
else if (anyRedosChange)
{
this.RaisePropertiesChanged(nameof(AnyRedos));
}
return(true);
}
public void Undo()
{
if (UndoList.Count > 0)
{
IUndoableAction act = UndoList.Pop();
act.Undo(this);
OnUndoChanged(UndoChangedEventArgs.Empty);
RedoList.Push(act);
OnRedoChanged(RedoChangedEventArgs.Empty);
}
}
public IAction Undo()
{
if (undoStack.Count() > 0)
{
IUndoableAction action = null;
while (undoStack.Count > 0)
{
action = undoStack.Last();
Logger.Log(LOGKEY, "undo action: " + action.ToString());
// before event
if (BeforePerformAction != null)
{
var arg = new ActionEventArgs(action, ActionBehavior.Undo);
BeforePerformAction(this, new ActionEventArgs(action, ActionBehavior.Undo));
if (arg.Cancel)
{
break;
}
}
undoStack.Remove(action);
action.Undo();
redoStack.Push(action);
// after event
AfterPerformAction?.Invoke(this, new ActionEventArgs(action, ActionBehavior.Undo));
if (!(action is ISerialUndoAction))
{
break;
}
}
return(action);
}
return(null);
}