traitsui.undo module

Defines the manager for Undo and Redo history for Traits user interface support.

class traitsui.undo.AbstractUndoItem

Bases: traits.has_traits.HasPrivateTraits

Abstract base class for undo items.

merge_undo(undo_item)

Merges two undo items if possible.

redo()

Re-does the change.

undo()

Undoes the change.

class traitsui.undo.ListUndoItem

Bases: traitsui.undo.AbstractUndoItem

A change to a list, which can be undone.

added = List()

Items added to the list

index = Int()

Starting index

merge_undo(undo_item)

Merges two undo items if possible.

name = Str()

Name of the trait that changed

object = Instance(HasTraits)

Object that the change occurred on

redo()

Re-does the change.

removed = List()

Items removed from the list

undo()

Undoes the change.

class traitsui.undo.UndoHistory

Bases: traits.has_traits.HasStrictTraits

Manages a list of undoable changes.

add(undo_item, extend=False)

Adds an UndoItem to the history.

can_redo = Property()

Can an action be redone?

can_undo = Property()

Can an action be undone?

clear()

Clears the undo history.

extend(undo_item)

Extends the undo history.

If possible the method merges the new UndoItem with the last item in the history; otherwise, it appends the new item.

history = List()

List of accumulated undo changes

now = Int()

The current position in the list

redo()

Redoes an operation.

redoable = Event(False)

Fired when state changes to redoable

revert()

Reverts all changes made so far and clears the history.

undo()

Undoes an operation.

undoable = Event(False)

Fired when state changes to undoable

class traitsui.undo.UndoHistoryUndoItem

Bases: traitsui.undo.AbstractUndoItem

An undo item for the undo history.

history = Instance(UndoHistory)

The undo history to undo or redo

redo()

Re-does the change.

undo()

Undoes the change.

class traitsui.undo.UndoItem

Bases: traitsui.undo.AbstractUndoItem

A change to an object trait, which can be undone.

merge_undo(undo_item)

Merges two undo items if possible.

name = Str()

Name of the trait that changed

new_value = Property()

New value of the changed trait

object = Instance(HasTraits)

Object the change occurred on

old_value = Property()

Old value of the changed trait

redo()

Re-does the change.

undo()

Undoes the change.