/// <summary>
/// Called when we want to undo a change in the model.
/// </summary>
/// <param name="clearUndoneModel">Set to false if you want it to
/// be possible to redo the action.</param>
internal void Undo(Boolean clearUndoneModel)
{
ModelHistoryItem historyItem = mModelHistory.Undo(clearUndoneModel);
if (historyItem != null)
{
mPlayModel = historyItem.model;
viewPanel.CurrentFrame = mPlayModel.GetFrame(viewPanel.CurrentFrame.UniqueId);
if (viewPanel.CurrentFrame == null)
{
viewPanel.CurrentFrame = mPlayModel.FirstFrame();
}
viewPanel.Refresh();
// Need to tell the frame collection that the model has changed as well
// since it usually finds out from the ModelChanged function of the
// main designer form (which isn't called during an undo).
frameCollection.ModelChanged(mPlayModel);
frameCollection.CurrentFrameChanged(viewPanel.CurrentFrame);
}
// Each time the model changes we check to see whether the undo/redo
// buttons should be greyed out.
undoToolStripMenuItem.Enabled = mModelHistory.CanUndo();
redoToolStripMenuItem.Enabled = mModelHistory.CanRedo();
}