[data-grid] Add a method to get all the real rows of a group created with row grouping

[flaviendelangle]

Duplicates

• I have searched the existing issues

Latest version

• I have tested the latest version

Summary 💡

See #4248 (comment)

Getting all the real rows (without auto-generated ones) of a group seems to be a common use case that we should make as easy as possible.

I think the method should be specific to the Row Grouping trees, because tree created with the Tree Data do not have the same needs.

It could look something like:

interface GroupingCriteriaRowGetter {
  applyFiltering?: boolean;
  applySorting?: boolean;
}

interface GridRowGroupingApi {
  // ... other methods
  getGroupingCriteriaRows: (params: GroupingCriteriaRowGetter) => GridRowEntrie[]
}

Examples 🌈

No response

Motivation 🔦

No response

Order ID 💳 (optional)

No response