How to use undo and redo function for annotations

Technical Support
1

I know hotkeys are available but I want to trigger undo and redo over a button click outside the viewer.
I have also tried trigger event for hotkeys but it doesn’t work.
Please suggest me something to use this default feature for undo and redo of annotations.

image
image1703×915 17.2 KB

How to use this methods?

      this.viewerInstance.CoreControls.AnnotationHistoryManager.undo();

This doesn’t work. Please let me know the actual way to invoke that method.

2

Hi!

To get reference to the history manager you can call docViewer.getAnnotationHistoryManager(), then you should have access to the APIs above. We will update the documenation to make this a bit more clear.

WebViewer((), ele).then(instance => {
   const { docViewer } = instance;
   const historyManager = docViewer.getAnnotationHistoryManager()

    historyManager.undo();
})

I hope this helps!
Thanks,
Logan