/// <summary>
/// Create a ChangeSet for the specified UndoRoot.
/// </summary>
/// <param name="undoRoot">The UndoRoot that this ChangeSet belongs to.</param>
/// <param name="description">A description of the change.</param>
/// <param name="change">The Change instance that can perform the undo / redo as needed.</param>
public ChangeSet(UndoRoot undoRoot, string description, Change change) {
_undoRoot = undoRoot;
_changes = new List<Change>();
_description = description;
if (null != change)
AddChange(change);
}
/// <summary>
/// Add a change to this ChangeSet.
/// </summary>
/// <param name="change"></param>
internal void AddChange(Change change) {
if (_undoRoot.ConsolidateChangesForSameInstance) {
//var dupes = _Changes.Where(c => null != c.ChangeKey && c.ChangeKey.Equals(change.ChangeKey)).ToList();
//if (null != dupes && dupes.Count > 0)
// dupes.ForEach(c => _Changes.Remove(c));
var dupe = _changes.FirstOrDefault(c => null != c.ChangeKey && c.ChangeKey.Equals(change.ChangeKey));
if (null != dupe) {
dupe.MergeWith(change);
// System.Diagnostics.Debug.WriteLine("AddChange: MERGED");
} else {
_changes.Add(change);
}
} else {
_changes.Add(change);
}
}
/// <summary> /// When consolidating events, we want to keep the original (first) "Undo" /// but use the most recent Redo. This will pull the Redo from the /// specified Change and apply it to this instance. /// </summary> public abstract void MergeWith(Change latestChange);
/// <summary>
/// When consolidating events, we want to keep the original "Undo"
/// but use the most recent Redo. This will pull the Redo from the
/// specified Change and apply it to this instance.
/// </summary>
public override void MergeWith(Change latestChange) {
var other = latestChange as DelegateChange;
if (null != other)
_redoAction = other._redoAction;
}
/// <summary>
/// Add a change to the Undo history. The change will be added to the existing batch, if in a batch.
/// Otherwise, a new ChangeSet will be created.
/// </summary>
/// <param name="change">The change to add to the history.</param>
/// <param name="description">The description of this change.</param>
public void AddChange(Change change, string description) {
// System.Diagnostics.Debug.WriteLine("Starting AddChange: " + description);
// We don't want to add additional changes representing the operations that happen when undoing or redoing a change.
if (_isUndoingOrRedoing)
return;
// If batched, add to the current ChangeSet, otherwise add a new ChangeSet.
if (IsInBatch) {
_currentBatchChangeSet.AddChange(change);
//System.Diagnostics.Debug.WriteLine("AddChange: BATCHED " + description);
} else {
_undoStack.Push(new ChangeSet(this, description, change));
OnUndoStackChanged();
//System.Diagnostics.Debug.WriteLine("AddChange: " + description);
}
// Prune the RedoStack
_redoStack.Clear();
OnRedoStackChanged();
}
/// <summary> /// When consolidating events, we want to keep the original (first) "Undo" /// but use the most recent Redo. This will pull the Redo from the /// specified Change and apply it to this instance. /// </summary> public abstract void MergeWith(Change latestChange);