A simple undo / redo manager. This was designed to work well with Replicache, but can be used entirely independently. From this library's perspective, undo/redo actions are just functions and this library doesn't care what those functions do. Please use Replidraw as a reference on how to use the library.
npm install @rocicorp/undo
import { Replicache } from "replicache";
import { useSubscribe } from "replicache-react";
...
import {UndoManager} from '@rocicorp/undo';
// Replicache and UndoManager are initialized outside of the initial component render.
// undoManager = new UndoManager()
const App = ({ rep }: { rep: Replicache<M>, undoManager: UndoManager }) => {
const todos = useSubscribe(rep, listTodos, [], [rep]);
// new item with undo
const handleNewItem = (text: string) => {
const id = nanoid();
//function that will redo and execute
const putTodo = () => {
rep.mutate.putTodo({
id,
text: text,
sort: todos.length > 0 ? todos[todos.length - 1].sort + 1 : 0,
completed: false,
});
};
//undo function
const removeTodo = () => rep.mutate.deleteTodos([id]);
undoManager.add({
execute: putTodo,
undo: removeTodo,
});
};
return (
<div>
<Header onNewItem={handleNewItem} />
<MainSection
todos={todos}
/>
</div>
);
}
import {UndoManager} from '@rocicorp/undo';
const undoManager = new UndoManager();
const modifiedValue = 0;
undoManager.add({
undo: () => {
modifiedValue--;
},
execute: () => {
modifiedValue++;
},
});
Constructor for UndoManager
Param | Type | Description |
---|---|---|
options | UnderManagerOptions |
Options passed for undo manager constructor |
UnderManagerOptions
Param | Type | Description |
---|---|---|
maxSize | Object |
The maximum number of entries in the stack. Default is 10000. |
onChange | (undoManager: UndoRedoStackState) => void |
A callback function to be called when the stack canUndo or canRedo values change. |
Example
const undoManager = new UndoManager({ 10, (e: UndoRedoStackState) => {
console.log('undo manager canUndo or canRedo values changed -- ', e.canUndo, e.canRedo);
}});
Determines if a user can perform the undo
operation on the undoRedo stack.
Determines if a user can perform the redo
operation on the undoRedo stack.
Adds an entry to the undoRedo stack.
Param | Type | Description |
---|---|---|
options | AddOptions |
A UndoRedo or ExecuteUndo object that can is added to the stack. If it is an ExecuteUndo it will run the execute function immediately after adding to the stack. |
type AddOptions = UndoRedo | ExecuteUndo;
type UndoRedo = {
redo: () => MaybePromise<void>;
undo: () => MaybePromise<void>;
};
type ExecuteUndo = {
execute: () => MaybePromise<void>;
undo: () => MaybePromise<void>;
};
Executes the undo function of the current entry in the undoRedo stack. If the current entry has groupID it will check the upcoming undo entry. If the upcoming undo entry also has the same groupID
the function will recursively call undo until it runs into a entry that has has a different groupID
or is undefined
.
Executes the redo function of the current entry in the undoRedo stack. If the current entry has groupID it will check the upcoming redo entry. If the upcoming redo entry also has the same groupID
the function will recursively call redo until it runs into a entry that has has a different groupID
or is undefined
.
Sets the undo manager to add groupID
to all subsequent entries. Sets the isGrouping
internal state of the stack to true
Sets the undo manager to mark all subsequent added entries groupID
to undefined
. Sets the isGrouping
internal state of the stack to false