UndoRedo

Documentation

Overview

Package UndoRedo provides methods for working with UndoRedo object instances.

Index

• type Advanced
• type Any
• type Instance
  • func New() Instance
  • func (self Instance) AddDoMethod(callable func())
  • func (self Instance) AddDoProperty(obj Object.Instance, property string, value any)
  • func (self Instance) AddDoReference(obj Object.Instance)
  • func (self Instance) AddUndoMethod(callable func())
  • func (self Instance) AddUndoProperty(obj Object.Instance, property string, value any)
  • func (self Instance) AddUndoReference(obj Object.Instance)
  • func (self Instance) AsObject() [1]gd.Object
  • func (self Instance) AsUndoRedo() Instance
  • func (self Instance) ClearHistory()
  • func (self Instance) CommitAction()
  • func (self Instance) CreateAction(name string)
  • func (self Instance) EndForceKeepInMergeEnds()
  • func (self Instance) GetActionName(id int) string
  • func (self Instance) GetCurrentAction() int
  • func (self Instance) GetCurrentActionName() string
  • func (self Instance) GetHistoryCount() int
  • func (self Instance) GetVersion() int
  • func (self Instance) HasRedo() bool
  • func (self Instance) HasUndo() bool
  • func (self Instance) IsCommittingAction() bool
  • func (self Instance) MaxSteps() int
  • func (self Instance) OnVersionChanged(cb func())
  • func (self Instance) Redo() bool
  • func (self Instance) SetMaxSteps(value int)
  • func (self Instance) StartForceKeepInMergeEnds()
  • func (self Instance) Undo() bool
  • func (self *Instance) UnsafePointer() unsafe.Pointer
  • func (self Instance) Virtual(name string) reflect.Value
• type MergeMode

Types

type Advanced

type Advanced = class

Advanced exposes a 1:1 low-level instance of the class, undocumented, for those who know what they are doing.

type Any

type Any interface {
	gd.IsClass
	AsUndoRedo() Instance
}

type Instance

type Instance [1]gdclass.UndoRedo

UndoRedo works by registering methods and property changes inside "actions". You can create an action, then provide ways to do and undo this action using function calls and property changes, then commit the action. When an action is committed, all of the [code]do_*[/code] methods will run. If the [method undo] method is used, the [code]undo_*[/code] methods will run. If the [method redo] method is used, once again, all of the [code]do_*[/code] methods will run. Here's an example on how to add an action: [codeblocks] [gdscript] var undo_redo = UndoRedo.new()

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_my_button_pressed():

var node = get_node("MyNode2D")
undo_redo.create_action("Move the node")
undo_redo.add_do_method(do_something)
undo_redo.add_undo_method(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()

[/gdscript] [csharp] private UndoRedo _undoRedo;

public override void _Ready()

{
    _undoRedo = new UndoRedo();
}

public void DoSomething()

{
    // Put your code here.
}

public void UndoSomething()

{
    // Put here the code that reverts what's done by "DoSomething()".
}

private void OnMyButtonPressed()

{
    var node = GetNode<Node2D>("MyNode2D");
    _undoRedo.CreateAction("Move the node");
    _undoRedo.AddDoMethod(new Callable(this, MethodName.DoSomething));
    _undoRedo.AddUndoMethod(new Callable(this, MethodName.UndoSomething));
    _undoRedo.AddDoProperty(node, "position", new Vector2(100, 100));
    _undoRedo.AddUndoProperty(node, "position", node.Position);
    _undoRedo.CommitAction();
}

[/csharp] [/codeblocks] Before calling any of the [code]add_(un)do_*[/code] methods, you need to first call [method create_action]. Afterwards you need to call [method commit_action]. If you don't need to register a method, you can leave [method add_do_method] and [method add_undo_method] out; the same goes for properties. You can also register more than one method/property. If you are making an [EditorPlugin] and want to integrate into the editor's undo history, use [EditorUndoRedoManager] instead. If you are registering multiple properties/method which depend on one another, be aware that by default undo operation are called in the same order they have been added. Therefore instead of grouping do operation with their undo operations it is better to group do on one side and undo on the other as shown below. [codeblocks] [gdscript] undo_redo.create_action("Add object")

# DO undo_redo.add_do_method(_create_object) undo_redo.add_do_method(_add_object_to_singleton)

# UNDO undo_redo.add_undo_method(_remove_object_from_singleton) undo_redo.add_undo_method(_destroy_that_object)

undo_redo.commit_action() [/gdscript] [csharp] _undo_redo.CreateAction("Add object");

// DO _undo_redo.AddDoMethod(new Callable(this, MethodName.CreateObject)); _undo_redo.AddDoMethod(new Callable(this, MethodName.AddObjectToSingleton));

// UNDO _undo_redo.AddUndoMethod(new Callable(this, MethodName.RemoveObjectFromSingleton)); _undo_redo.AddUndoMethod(new Callable(this, MethodName.DestroyThatObject));

_undo_redo.CommitAction(); [/csharp] [/codeblocks]

var Nil Instance

Nil is a nil/null instance of the class. Equivalent to the zero value.

func New

func New() Instance

func (Instance) AddDoMethod

func (self Instance) AddDoMethod(callable func())

Register a [Callable] that will be called when the action is committed.

func (Instance) AddDoProperty

func (self Instance) AddDoProperty(obj Object.Instance, property string, value any)

Register a [param property] that would change its value to [param value] when the action is committed.

func (Instance) AddDoReference

func (self Instance) AddDoReference(obj Object.Instance)

Register a reference to an object that will be erased if the "do" history is deleted. This is useful for objects added by the "do" action and removed by the "undo" action. When the "do" history is deleted, if the object is a [RefCounted], it will be unreferenced. Otherwise, it will be freed. Do not use for resources. [codeblock] var node = Node2D.new() undo_redo.create_action("Add node") undo_redo.add_do_method(add_child.bind(node)) undo_redo.add_do_reference(node) undo_redo.add_undo_method(remove_child.bind(node)) undo_redo.commit_action() [/codeblock]

func (Instance) AddUndoMethod

func (self Instance) AddUndoMethod(callable func())

Register a [Callable] that will be called when the action is undone.

func (Instance) AddUndoProperty

func (self Instance) AddUndoProperty(obj Object.Instance, property string, value any)

Register a [param property] that would change its value to [param value] when the action is undone.

func (Instance) AddUndoReference

func (self Instance) AddUndoReference(obj Object.Instance)

Register a reference to an object that will be erased if the "undo" history is deleted. This is useful for objects added by the "undo" action and removed by the "do" action. When the "undo" history is deleted, if the object is a [RefCounted], it will be unreferenced. Otherwise, it will be freed. Do not use for resources. [codeblock] var node = $Node2D undo_redo.create_action("Remove node") undo_redo.add_do_method(remove_child.bind(node)) undo_redo.add_undo_method(add_child.bind(node)) undo_redo.add_undo_reference(node) undo_redo.commit_action() [/codeblock]

func (Instance) AsObject

func (self Instance) AsObject() [1]gd.Object

func (Instance) AsUndoRedo

func (self Instance) AsUndoRedo() Instance

func (Instance) ClearHistory

func (self Instance) ClearHistory()

Clear the undo/redo history and associated references. Passing [code]false[/code] to [param increase_version] will prevent the version number from increasing when the history is cleared.

func (Instance) CommitAction

func (self Instance) CommitAction()

Commit the action. If [param execute] is [code]true[/code] (which it is by default), all "do" methods/properties are called/set when this function is called.

func (Instance) CreateAction

func (self Instance) CreateAction(name string)

Create a new action. After this is called, do all your calls to [method add_do_method], [method add_undo_method], [method add_do_property], and [method add_undo_property], then commit the action with [method commit_action]. The way actions are merged is dictated by [param merge_mode]. See [enum MergeMode] for details. The way undo operation are ordered in actions is dictated by [param backward_undo_ops]. When [param backward_undo_ops] is [code]false[/code] undo option are ordered in the same order they were added. Which means the first operation to be added will be the first to be undone.

func (Instance) EndForceKeepInMergeEnds

func (self Instance) EndForceKeepInMergeEnds()

Stops marking operations as to be processed even if the action gets merged with another in the [constant MERGE_ENDS] mode. See [method start_force_keep_in_merge_ends].

func (Instance) GetActionName

func (self Instance) GetActionName(id int) string

Gets the action name from its index.

func (Instance) GetCurrentAction

func (self Instance) GetCurrentAction() int

Gets the index of the current action.

func (Instance) GetCurrentActionName

func (self Instance) GetCurrentActionName() string

Gets the name of the current action, equivalent to [code]get_action_name(get_current_action())[/code].

func (Instance) GetHistoryCount

func (self Instance) GetHistoryCount() int

Returns how many elements are in the history.

func (Instance) GetVersion

func (self Instance) GetVersion() int

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.

func (Instance) HasRedo

func (self Instance) HasRedo() bool

Returns [code]true[/code] if a "redo" action is available.

func (Instance) HasUndo

func (self Instance) HasUndo() bool

Returns [code]true[/code] if an "undo" action is available.

func (Instance) IsCommittingAction

func (self Instance) IsCommittingAction() bool

Returns [code]true[/code] if the [UndoRedo] is currently committing the action, i.e. running its "do" method or property change (see [method commit_action]).

func (Instance) MaxSteps

func (self Instance) MaxSteps() int

func (Instance) OnVersionChanged

func (self Instance) OnVersionChanged(cb func())

func (Instance) Redo

func (self Instance) Redo() bool

Redo the last action.

func (Instance) SetMaxSteps

func (self Instance) SetMaxSteps(value int)

func (Instance) StartForceKeepInMergeEnds

func (self Instance) StartForceKeepInMergeEnds()

Marks the next "do" and "undo" operations to be processed even if the action gets merged with another in the [constant MERGE_ENDS] mode. Return to normal operation using [method end_force_keep_in_merge_ends].

func (Instance) Undo

func (self Instance) Undo() bool

Undo the last action.

func (*Instance) UnsafePointer

func (self *Instance) UnsafePointer() unsafe.Pointer

func (Instance) Virtual

func (self Instance) Virtual(name string) reflect.Value

type MergeMode

type MergeMode = gdclass.UndoRedoMergeMode //gd:UndoRedo.MergeMode

const (
	/*Makes "do"/"undo" operations stay in separate actions.*/
	MergeDisable MergeMode = 0
	/*Merges this action with the previous one if they have the same name. Keeps only the first action's "undo" operations and the last action's "do" operations. Useful for sequential changes to a single value.*/
	MergeEnds MergeMode = 1
	/*Merges this action with the previous one if they have the same name.*/
	MergeAll MergeMode = 2
)