record::extension

The record::extension module provides functionality for making undo and redo requests from outside the Reactor using events and triggers.

Types

RequestUndo

#![allow(unused)]
fn main() {
enum RequestUndo<Act> {
    Once,
    IndexTo(usize),
    To(Act),
    All,
}
}

Represents a request to undo operations. If an undo or redo is already in progress, the request will be ignored.

• Once: Corresponds to record::undo::once
• IndexTo(usize): Corresponds to record::undo::index_to
• To(Act): Corresponds to record::undo::to
• All: Corresponds to record::undo::all

RequestRedo

#![allow(unused)]
fn main() {
enum RequestRedo<Act> {
    Once,
    IndexTo(usize),
    To(Act),
    All,
}
}

Represents a request to redo operations. If an undo or redo is already in progress, the request will be ignored.

• Once: Corresponds to record::redo::once
• IndexTo(usize): Corresponds to record::redo::index_to
• To(Act): Corresponds to record::redo::to
• All: Corresponds to record::redo::all

Traits

RecordExtension

#![allow(unused)]
fn main() {
trait RecordExtension {
    fn add_record<Act>(&mut self) -> &mut Self
    where
        Act: Clone + PartialEq + Send + Sync + 'static;
}
}

Allows undo and redo requests to be made using RequestUndo and RequestRedo from outside the Reactor.

Methods

• add_record<Act>: Sets up RequestUndo and RequestRedo and their associated systems.

Examples

Using Events

#![allow(unused)]
fn main() {
use bevy::prelude::*;
use bevy_flurx::prelude::*;

#[derive(Resource, Default)]
struct UndoRedoState {
    can_undo: bool,
    can_redo: bool,
}

fn setup_app(app: &mut App) {
    // Add record functionality for your operation type
    app.add_record::<MyOperation>();
}

fn update_ui_system(
    mut ui_state: ResMut<UndoRedoState>,
    record: Res<Record<MyOperation>>,
) {
    ui_state.can_undo = !record.tracks.is_empty();
    ui_state.can_redo = !record.redo.is_empty();
}

fn handle_input(
    keys: Res<Input<KeyCode>>,
    mut undo_events: MessageWriter<RequestUndo<MyOperation>>,
    mut redo_events: MessageWriter<RequestRedo<MyOperation>>,
) {
    // Handle Ctrl+Z for undo
    if keys.pressed(KeyCode::ControlLeft) && keys.just_pressed(KeyCode::Z) {
        undo_events.send(RequestUndo::Once);
    }
    
    // Handle Ctrl+Y for redo
    if keys.pressed(KeyCode::ControlLeft) && keys.just_pressed(KeyCode::Y) {
        redo_events.send(RequestRedo::Once);
    }
}
}

Using Triggers

#![allow(unused)]
fn main() {
use bevy::prelude::*;
use bevy_flurx::prelude::*;

fn handle_button_click(
    interaction_query: Query<&Interaction, (Changed<Interaction>, With<UndoButton>)>,
    world: &mut World,
) {
    for interaction in interaction_query.iter() {
        if *interaction == Interaction::Clicked {
            // Trigger an undo operation
            world.trigger(RequestUndo::<MyOperation>::Once);
        }
    }
}
}

How It Works

When you call app.add_record::<Act>(), the following happens:

1. The Record<Act> resource is initialized
2. Event types for RequestUndo<Act> and RequestRedo<Act> are registered
3. Systems are added to handle these events and triggers

When a RequestUndo or RequestRedo event is sent or triggered:

1. The corresponding system creates a new Reactor
2. The Reactor executes the appropriate undo or redo action
3. If the action fails (e.g., because an undo or redo is already in progress), the error is ignored

When to Use

Use the extension module when you need to:

• Trigger undo/redo operations from UI elements
• Handle keyboard shortcuts for undo/redo
• Integrate undo/redo functionality with other systems in your application

This module is particularly useful for applications with complex UI that need to provide undo/redo functionality through various means (buttons, keyboard shortcuts, etc.).