public void Push(UndoAction action)
{
// Remove any "redo" actions from the history.
// +---+ +---+ +---+ +---+ +---+
// | 0 | > | 1 | > | 2 | > | 3 | > | 4 |
// +---+ +---+ +---+ +---+ +---+
// ^current
// count = 5; current = 2;
// Remove the last 2 items.
int nCount = m_history.Count;
if (nCount > m_nCurrent + 1)
{
m_history.RemoveRange(m_nCurrent + 1, nCount - (m_nCurrent + 1));
if (m_owner != null)
{
m_owner.RemoveUndoRange(m_id, m_nCurrent + 1, nCount - (m_nCurrent + 1));
}
}
// Add the new item at the end.
// +---+ +---+ +---+ +---+
// | 0 | > | 1 | > | 2 | > | N |
// +---+ +---+ +---+ +---+
// ^old ^current
m_history.Add(action);
m_nCurrent++;
if (m_owner != null)
{
m_owner.AddUndo(m_id, action);
m_owner.SetCurrentUndo(m_id, m_nCurrent);
}
// Remove the oldest action if the stack is too large.
// +---+ +---+ +---+
// | 1 | > | 2 | > | N |
// +---+ +---+ +---+
// ^current
if (m_history.Count > k_nMaxUndoHistory)
{
m_history.RemoveAt(0);
m_nCurrent--;
if (m_owner != null)
{
m_owner.RemoveUndo(m_id, 0);
m_owner.SetCurrentUndo(m_id, m_nCurrent);
}
}
}
public void Add(TabMgr.TabId id, UndoAction action)
{
ListBox lb = GetListbox(id);
lb.Items.Add(action.Description);
}
public void AddUndo(TabMgr.TabId id, UndoAction action)
{
m_undoHistory.Add(id, action);
}