godot-docs/classes/class_undoredo.rst

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.. DO NOT EDIT THIS FILE!!!
.. Generated automatically from Godot engine sources.
.. Generator: https://github.com/godotengine/godot/tree/3.6/doc/tools/make_rst.py.
.. XML source: https://github.com/godotengine/godot/tree/3.6/doc/classes/UndoRedo.xml.

.. _class_UndoRedo:

UndoRedo
========

**Inherits:** :ref:`Object<class_Object>`

Helper to manage undo/redo operations in the editor or custom tools.

.. rst-class:: classref-introduction-group

Description
-----------

Helper to manage undo/redo operations in the editor or custom tools. It works by registering methods and property changes inside "actions".

Common behavior is to create an action, then add do/undo calls to functions or property changes, then committing the action.

Here's an example on how to add an action to the Godot editor's own **UndoRedo**, from a plugin:

::

    var undo_redo = get_undo_redo() # Method of EditorPlugin.
    
    func do_something():
        pass # Put your code here.
    
    func undo_something():
        pass # Put here the code that reverts what's done by "do_something()".
    
    func _on_MyButton_pressed():
        var node = get_node("MyNode2D")
        undo_redo.create_action("Move the node")
        undo_redo.add_do_method(self, "do_something")
        undo_redo.add_undo_method(self, "undo_something")
        undo_redo.add_do_property(node, "position", Vector2(100,100))
        undo_redo.add_undo_property(node, "position", node.position)
        undo_redo.commit_action()

\ :ref:`create_action<class_UndoRedo_method_create_action>`, :ref:`add_do_method<class_UndoRedo_method_add_do_method>`, :ref:`add_undo_method<class_UndoRedo_method_add_undo_method>`, :ref:`add_do_property<class_UndoRedo_method_add_do_property>`, :ref:`add_undo_property<class_UndoRedo_method_add_undo_property>`, and :ref:`commit_action<class_UndoRedo_method_commit_action>` should be called one after the other, like in the example. Not doing so could lead to crashes.

If you don't need to register a method, you can leave :ref:`add_do_method<class_UndoRedo_method_add_do_method>` and :ref:`add_undo_method<class_UndoRedo_method_add_undo_method>` out; the same goes for properties. You can also register more than one method/property.

.. rst-class:: classref-reftable-group

Methods
-------

.. table::
   :widths: auto

   +-----------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | void                        | :ref:`add_do_method<class_UndoRedo_method_add_do_method>` **(** :ref:`Object<class_Object>` object, :ref:`String<class_String>` method, ... **)** |vararg|                                  |
   +-----------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | void                        | :ref:`add_do_property<class_UndoRedo_method_add_do_property>` **(** :ref:`Object<class_Object>` object, :ref:`String<class_String>` property, :ref:`Variant<class_Variant>` value **)**     |
   +-----------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | void                        | :ref:`add_do_reference<class_UndoRedo_method_add_do_reference>` **(** :ref:`Object<class_Object>` object **)**                                                                              |
   +-----------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | void                        | :ref:`add_undo_method<class_UndoRedo_method_add_undo_method>` **(** :ref:`Object<class_Object>` object, :ref:`String<class_String>` method, ... **)** |vararg|                              |
   +-----------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | void                        | :ref:`add_undo_property<class_UndoRedo_method_add_undo_property>` **(** :ref:`Object<class_Object>` object, :ref:`String<class_String>` property, :ref:`Variant<class_Variant>` value **)** |
   +-----------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | void                        | :ref:`add_undo_reference<class_UndoRedo_method_add_undo_reference>` **(** :ref:`Object<class_Object>` object **)**                                                                          |
   +-----------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | void                        | :ref:`clear_history<class_UndoRedo_method_clear_history>` **(** :ref:`bool<class_bool>` increase_version=true **)**                                                                         |
   +-----------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | void                        | :ref:`commit_action<class_UndoRedo_method_commit_action>` **(** **)**                                                                                                                       |
   +-----------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | void                        | :ref:`create_action<class_UndoRedo_method_create_action>` **(** :ref:`String<class_String>` name, :ref:`MergeMode<enum_UndoRedo_MergeMode>` merge_mode=0 **)**                              |
   +-----------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | :ref:`String<class_String>` | :ref:`get_current_action_name<class_UndoRedo_method_get_current_action_name>` **(** **)** |const|                                                                                           |
   +-----------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | :ref:`int<class_int>`       | :ref:`get_version<class_UndoRedo_method_get_version>` **(** **)** |const|                                                                                                                   |
   +-----------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | :ref:`bool<class_bool>`     | :ref:`has_redo<class_UndoRedo_method_has_redo>` **(** **)** |const|                                                                                                                         |
   +-----------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | :ref:`bool<class_bool>`     | :ref:`has_undo<class_UndoRedo_method_has_undo>` **(** **)** |const|                                                                                                                         |
   +-----------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | :ref:`bool<class_bool>`     | :ref:`is_commiting_action<class_UndoRedo_method_is_commiting_action>` **(** **)** |const|                                                                                                   |
   +-----------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | :ref:`bool<class_bool>`     | :ref:`redo<class_UndoRedo_method_redo>` **(** **)**                                                                                                                                         |
   +-----------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | :ref:`bool<class_bool>`     | :ref:`undo<class_UndoRedo_method_undo>` **(** **)**                                                                                                                                         |
   +-----------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+

.. rst-class:: classref-section-separator

----

.. rst-class:: classref-descriptions-group

Signals
-------

.. _class_UndoRedo_signal_version_changed:

.. rst-class:: classref-signal

**version_changed** **(** **)**

Called when :ref:`undo<class_UndoRedo_method_undo>` or :ref:`redo<class_UndoRedo_method_redo>` was called.

.. rst-class:: classref-section-separator

----

.. rst-class:: classref-descriptions-group

Enumerations
------------

.. _enum_UndoRedo_MergeMode:

.. rst-class:: classref-enumeration

enum **MergeMode**:

.. _class_UndoRedo_constant_MERGE_DISABLE:

.. rst-class:: classref-enumeration-constant

:ref:`MergeMode<enum_UndoRedo_MergeMode>` **MERGE_DISABLE** = ``0``

Makes "do"/"undo" operations stay in separate actions.

.. _class_UndoRedo_constant_MERGE_ENDS:

.. rst-class:: classref-enumeration-constant

:ref:`MergeMode<enum_UndoRedo_MergeMode>` **MERGE_ENDS** = ``1``

Makes so that the action's "do" operation is from the first action created and the "undo" operation is from the last subsequent action with the same name.

.. _class_UndoRedo_constant_MERGE_ALL:

.. rst-class:: classref-enumeration-constant

:ref:`MergeMode<enum_UndoRedo_MergeMode>` **MERGE_ALL** = ``2``

Makes subsequent actions with the same name be merged into one.

.. rst-class:: classref-section-separator

----

.. rst-class:: classref-descriptions-group

Method Descriptions
-------------------

.. _class_UndoRedo_method_add_do_method:

.. rst-class:: classref-method

void **add_do_method** **(** :ref:`Object<class_Object>` object, :ref:`String<class_String>` method, ... **)** |vararg|

Register a method that will be called when the action is committed.

.. rst-class:: classref-item-separator

----

.. _class_UndoRedo_method_add_do_property:

.. rst-class:: classref-method

void **add_do_property** **(** :ref:`Object<class_Object>` object, :ref:`String<class_String>` property, :ref:`Variant<class_Variant>` value **)**

Register a property value change for "do".

.. rst-class:: classref-item-separator

----

.. _class_UndoRedo_method_add_do_reference:

.. rst-class:: classref-method

void **add_do_reference** **(** :ref:`Object<class_Object>` object **)**

Register a reference for "do" that will be erased if the "do" history is lost. This is useful mostly for new nodes created for the "do" call. Do not use for resources.

.. rst-class:: classref-item-separator

----

.. _class_UndoRedo_method_add_undo_method:

.. rst-class:: classref-method

void **add_undo_method** **(** :ref:`Object<class_Object>` object, :ref:`String<class_String>` method, ... **)** |vararg|

Register a method that will be called when the action is undone.

.. rst-class:: classref-item-separator

----

.. _class_UndoRedo_method_add_undo_property:

.. rst-class:: classref-method

void **add_undo_property** **(** :ref:`Object<class_Object>` object, :ref:`String<class_String>` property, :ref:`Variant<class_Variant>` value **)**

Register a property value change for "undo".

.. rst-class:: classref-item-separator

----

.. _class_UndoRedo_method_add_undo_reference:

.. rst-class:: classref-method

void **add_undo_reference** **(** :ref:`Object<class_Object>` object **)**

Register a reference for "undo" that will be erased if the "undo" history is lost. This is useful mostly for nodes removed with the "do" call (not the "undo" call!).

.. rst-class:: classref-item-separator

----

.. _class_UndoRedo_method_clear_history:

.. rst-class:: classref-method

void **clear_history** **(** :ref:`bool<class_bool>` increase_version=true **)**

Clear the undo/redo history and associated references.

Passing ``false`` to ``increase_version`` will prevent the version number to be increased from this.

.. rst-class:: classref-item-separator

----

.. _class_UndoRedo_method_commit_action:

.. rst-class:: classref-method

void **commit_action** **(** **)**

Commit the action. All "do" methods/properties are called/set when this function is called.

.. rst-class:: classref-item-separator

----

.. _class_UndoRedo_method_create_action:

.. rst-class:: classref-method

void **create_action** **(** :ref:`String<class_String>` name, :ref:`MergeMode<enum_UndoRedo_MergeMode>` merge_mode=0 **)**

Create a new action. After this is called, do all your calls to :ref:`add_do_method<class_UndoRedo_method_add_do_method>`, :ref:`add_undo_method<class_UndoRedo_method_add_undo_method>`, :ref:`add_do_property<class_UndoRedo_method_add_do_property>`, and :ref:`add_undo_property<class_UndoRedo_method_add_undo_property>`, then commit the action with :ref:`commit_action<class_UndoRedo_method_commit_action>`.

The way actions are merged is dictated by the ``merge_mode`` argument. See :ref:`MergeMode<enum_UndoRedo_MergeMode>` for details.

.. rst-class:: classref-item-separator

----

.. _class_UndoRedo_method_get_current_action_name:

.. rst-class:: classref-method

:ref:`String<class_String>` **get_current_action_name** **(** **)** |const|

Gets the name of the current action.

.. rst-class:: classref-item-separator

----

.. _class_UndoRedo_method_get_version:

.. rst-class:: classref-method

:ref:`int<class_int>` **get_version** **(** **)** |const|

Gets the version. Every time a new action is committed, the **UndoRedo**'s version number is increased automatically.

This is useful mostly to check if something changed from a saved version.

.. rst-class:: classref-item-separator

----

.. _class_UndoRedo_method_has_redo:

.. rst-class:: classref-method

:ref:`bool<class_bool>` **has_redo** **(** **)** |const|

Returns ``true`` if a "redo" action is available.

.. rst-class:: classref-item-separator

----

.. _class_UndoRedo_method_has_undo:

.. rst-class:: classref-method

:ref:`bool<class_bool>` **has_undo** **(** **)** |const|

Returns ``true`` if an "undo" action is available.

.. rst-class:: classref-item-separator

----

.. _class_UndoRedo_method_is_commiting_action:

.. rst-class:: classref-method

:ref:`bool<class_bool>` **is_commiting_action** **(** **)** |const|

Returns ``true`` if the **UndoRedo** is currently committing the action, i.e. running its "do" method or property change (see :ref:`commit_action<class_UndoRedo_method_commit_action>`).

.. rst-class:: classref-item-separator

----

.. _class_UndoRedo_method_redo:

.. rst-class:: classref-method

:ref:`bool<class_bool>` **redo** **(** **)**

Redo the last action.

.. rst-class:: classref-item-separator

----

.. _class_UndoRedo_method_undo:

.. rst-class:: classref-method

:ref:`bool<class_bool>` **undo** **(** **)**

Undo the last action.

.. |virtual| replace:: :abbr:`virtual (This method should typically be overridden by the user to have any effect.)`
.. |const| replace:: :abbr:`const (This method has no side effects. It doesn't modify any of the instance's member variables.)`
.. |vararg| replace:: :abbr:`vararg (This method accepts any number of arguments after the ones described here.)`
.. |static| replace:: :abbr:`static (This method doesn't need an instance to be called, so it can be called directly using the class name.)`