Getting scrolling (e.g. on typing) to work in virtualized lists about dev

[marijnh]

Does patch codemirror/view@1ecb5f1 look like it would work for you?

[krassowski]

I am checking if the new docViewUpdate could help here...

[krassowski]

No, docViewUpdate does not get called on cursor movement.

I can still use update() but this involves a lot of filtering down of undesirable updates. The problem when used from TypeScript is that view.viewState.scrollTarget is not exposed because viewState is marked as internal. If we could probe whether scrollTarget is defined I can handle this in update listener:

My current solution comes down to:

ViewPlugin.define((view) => {
  return {
    update: () => {
      // @ts-ignore
      const scrollTarget = view.viewState.scrollTarget;
      if (scrollTarget) {
        scrollVirtualizedListToEditor(scrollTarget);
      }
    }
  };
})

or equivalently:

EditorView.updateListener.of((viewUpdate) => {
  // @ts-ignore
  const scrollTarget = viewUpdate.view.viewState.scrollTarget;
  if (scrollTarget) {
      scrollVirtualizedListToEditor(scrollTarget);
  }
})

Would you consider exposing scrollTarget via getter on EditorView? If not, what about having a new scroll entry point like below?

ViewPlugin.define((view) => {
  return {
    scroll: (scrollTarget: ScrollTarget) => {
      scrollVirtualizedListToEditor(scrollTarget);
    }
  };
})

[krassowski]

Yes, this looks like it should do it, thank you!

[marijnh]

Released as part of @codemirror/view 6.26.0