useUndoRedo

Undo and redo commands with their availability.

const { undo, redo, canUndo, canRedo } = useUndoRedo()

• canUndo and canRedo re-render the component as the history changes; use them to disable the buttons.
• undo and redo throw DocumentNotLoadedError when no document is loaded.

Behavior

• The history tracks the local user's edits: undo reverts your changes.
• Edits made within 500 ms of each other merge into a single undo step. To keep an operation in its own step, use useUndoBoundary.
• Undo and redo return the document revision to its earlier value, so an "unsaved changes" indicator clears when all edits since the last save are undone.
• Changes applied with excludeFromHistory (see useSetWidgetProps and useSetParagraphProps) never enter the history.

Example

import { useUndoRedo } from '@sdk-pdf/react'

function UndoRedoButtons() {
  const { undo, redo, canUndo, canRedo } = useUndoRedo()

  return (
    <>
      <button disabled={!canUndo} onClick={undo}>
        Undo
      </button>
      <button disabled={!canRedo} onClick={redo}>
        Redo
      </button>
    </>
  )
}