protected virtual void OnUndoRedoState()
{
if (UndoRedoState != null)
{
UndoRedoState.Invoke(this, System.EventArgs.Empty);
}
}
public static void Do <T>(this UndoRedoState <T> undoRedoState, IEnumerable <T> items)
{
ArgumentNullException.ThrowIfNull(undoRedoState);
ArgumentNullException.ThrowIfNull(items);
var unprocessedItemCount = undoRedoState.GetUnprocessedItemCount();
if (unprocessedItemCount > 0)
{
undoRedoState.Items.RemoveRange(undoRedoState.ProcessedItemCount, unprocessedItemCount);
}
var itemList = items.ToList();
undoRedoState.Items.AddRange(itemList);
undoRedoState.ProcessedItemCount += itemList.Count;
}
public static void Undo <T>(this UndoRedoState <T> undoRedoState, int itemCount, Action <IReadOnlyList <T> > process)
{
ArgumentNullException.ThrowIfNull(undoRedoState);
Assert.IsInRange(itemCount > 0);
ArgumentNullException.ThrowIfNull(process);
if (undoRedoState.ProcessedItemCount < itemCount)
{
throw new InvalidOperationException("Nincs meg a megadott darabszámú visszavonható művelet.");
}
var processedItemCount = undoRedoState.ProcessedItemCount - itemCount;
var items = undoRedoState.Items.Take(processedItemCount).ToList();
process(items);
undoRedoState.ProcessedItemCount = processedItemCount;
}
public static void Redo <T>(this UndoRedoState <T> undoRedoState, int itemCount, Action <IReadOnlyList <T> > process)
{
ArgumentNullException.ThrowIfNull(undoRedoState);
Assert.IsInRange(itemCount > 0);
ArgumentNullException.ThrowIfNull(process);
var unprocessedItemCount = undoRedoState.GetUnprocessedItemCount();
if (unprocessedItemCount < itemCount)
{
throw new InvalidOperationException("Nincs meg a megadott számú ismételhető művelet.");
}
var items = undoRedoState.Items.GetRange(undoRedoState.ProcessedItemCount, itemCount).ToList();
process(items);
undoRedoState.ProcessedItemCount += itemCount;
}
/// <summary>
/// Commits the provided transaction.
/// </summary>
/// <param name="transaction">The transaction to commit.</param>
/// <exception cref="ArgumentNullException"><paramref name="transaction"/> is a <see langword="null"/> reference.</exception>
/// <exception cref="ArgumentException">The <see cref="UndoManager"/> does not contain <paramref name="transaction"/>.</exception>
void ITransactionManager.CommitTransaction(IInvokableTransaction transaction)
{
if (transaction == null)
{
throw new ArgumentNullException("transaction");
}
if (!this.openTransactions.Contains(transaction))
{
throw new ArgumentException("Cannot find the transaction to commit", "transaction");
}
// only switch the state to committing if the undo manager is not doing another task (e.g. undoing).
UndoRedoState currentState = this.state == UndoRedoState.Idle ? UndoRedoState.Committing : this.state;
using (new StateSwitcher(this, currentState))
{
while (this.openTransactions.Contains(transaction))
{
IInvokableTransaction toCommit = this.openTransactions.Pop();
if (toCommit.Any())
{
if (toCommit.Equals(transaction))
{
Stack <IInvokableTransaction> history = this.IsUndoing ? this.redoHistory : this.undoHistory;
history.Push(transaction);
}
else
{
IInvokableTransaction topMost = this.openTransactions.Peek();
topMost.RegisterInvokation(toCommit);
}
}
}
}
}
private static int GetUnprocessedItemCount <T>(this UndoRedoState <T> undoRedoState)
{
ArgumentNullException.ThrowIfNull(undoRedoState);
return(undoRedoState.Items.Count - undoRedoState.ProcessedItemCount);
}
