TreeUndoManager Class Reference

Owns the cell-tree undo/redo stacks and the active-cell snapshot. More...

#include <TreeUndoManager.h>

Public Member Functions
UndoActions &	UndoStack ()
	The list of tree actions that can be undone.
const UndoActions &	UndoStack () const
UndoActions &	RedoStack ()
	The list of undone tree actions that can be redone.
const UndoActions &	RedoStack () const
void	AppendAction ()
	Mark the newest undo action as part of the following atomic action.
void	ClearRedoActionList ()
	Clear the list of actions that can be redone.
void	ClearUndoActionList ()
	Clear the list of actions that can be undone.
void	ClearBuffers ()
	Clear both action lists and forget the active-cell snapshot.
void	LimitUndoBuffer (long undoLimit)
	Drop actions from the back of the undo list until it is within the limit.
void	CellEntered (GroupCell *group, const wxString &text, long long selStart, long long selEnd)
	The cursor has entered a cell: snapshot its contents.
bool	CellLeft (GroupCell *activeCell, const wxString &currentText, long undoLimit)
	The cursor is leaving a cell: record a text-change undo action if needed.
void	ForgetActiveCell ()
	Forget the active-cell snapshot (e.g. the next change must not be undoable).
GroupCell *	ActiveCell () const
	The cell the cursor is in, as recorded by CellEntered().

Static Public Member Functions
static void	DiscardAction (UndoActions *actionList)
	Remove one action from an action list.
static void	AppendAction (UndoActions *actionList)
	Mark the newest action of the list as part of the following atomic action.

Detailed Description

Owns the cell-tree undo/redo stacks and the active-cell snapshot.

Pure state + bookkeeping: this class never touches the worksheet's cell tree itself. Applying an action (the tree surgery) is Worksheet's job; it reaches the stacks via UndoStack()/RedoStack().

The "active cell snapshot" is the text and selection an EditorCell had when the cursor entered it; when the cursor leaves the cell again, the snapshot is compared against the current text to decide whether a text-change undo action has to be recorded (see CellLeft()).

Member Function Documentation

CellEntered()

void TreeUndoManager::CellEntered ( GroupCell *  group, const wxString &  text, long long  selStart, long long  selEnd  )

inline

The cursor has entered a cell: snapshot its contents.

Parameters

group	The group cell that was entered
text	The text its editor currently contains
selStart	The editor's selection start (or cursor position)
selEnd	The editor's selection end (or cursor position)

CellLeft()

bool TreeUndoManager::CellLeft ( GroupCell *  activeCell, const wxString &  currentText, long  undoLimit  )

inline

The cursor is leaving a cell: record a text-change undo action if needed.

Compares the entry snapshot with the cell's current text; if the text has genuinely changed (more than just appending a ";"), an undo action with the old text and selection is pushed, the undo buffer is limited and the redo list is cleared.

Parameters

activeCell	The group cell being left
currentText	The text its editor contains now
undoLimit	The undo-buffer limit to enforce (0 = unlimited)

Returns

true if a text-change action was recorded

DiscardAction()

static void TreeUndoManager::DiscardAction ( UndoActions *  actionList )

inlinestatic

Remove one action from an action list.

Removes the whole atomic group: trailing actions that are marked as m_partOfAtomicAction belong to the action in front of them and are dropped along with it.

LimitUndoBuffer()

void TreeUndoManager::LimitUndoBuffer ( long  undoLimit )

inline

Drop actions from the back of the undo list until it is within the limit.

Parameters

undoLimit

The maximum number of undo actions to keep; 0 = unlimited.

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The documentation for this class was generated from the following file:

• src/TreeUndoManager.h