Grid and GridPro don’t offer a straightforward way to add a single item

[subITCSS]

Currently, if we want to add or remove just one object in the grid, we have to call setItems, which replaces the entire data set. When the underlying data source is large—for example, 1,000 items, this causes noticeable delays as the grid re-renders everything.
New methods to add or remove a single item without calling setItems should be introduced. The given item should be inserted into or removed from the grid directly, depending on the operation, without forcing a full re-render of all items.

[Legioth]

as the grid re-renders everything

Grid only re-renders the visible items but not all items. But what might become problematic is the way you have to create a new items array with one more item to run setItems again.

As a workaround, you can use a callback data provider that is backed by your own in-memory list ArrayList or similar. In that case, you just need to do dataProvider.refreshAll() after the backing list has been changed and that's a relatively cheap operation.

[mshabarov]

You can make it through grid.getListDataView().addItem(person), but ofc it invokes refreshAll internally.

[mshabarov]

This could be explained in our documentation.

We can perhaps design a new API that would add a new item to component directly and provides a way to add it to backed collection or datasource.

[christophersteinmann]

Any news here?

[mshabarov]

This is not a priority for us at the moment. We may want to get back to it at some point in the future if this would pop up to the top of the most voted feature requests.

[SavageCZ]

We also need this for live migration/import logs in Vaadin Grid.

In our case, a background migration reports tens of thousands of results progressively. Each result should be appended to the Grid immediately.

The current refreshAll() approach creates unnecessary overhead, because adding items one by one can repeatedly refresh or re-evaluate the whole dataset instead of performing a cheap single-item append operation. This becomes visible with larger imports.

A proper append/add single item API without refreshing the whole dataset would help a lot.