Has row expander
/documentation/pages/Guides/Mobile and Web Components/Grid/Grid Properties/Row Expander/Has row expander.xml
The row expander is another method to show information related to a record on a row. A column is added with a 'plus'   icon that can be selected to 'expand the row'. A minus  icon will be shown after the row is expanded that can be selected to close the expanded row. There are 2 row expander types.
Row expander type
/documentation/pages/Guides/Mobile and Web Components/Grid/Grid Properties/Row Expander/Row expander type.xml
The ' LinkedGrids ' option allows selecting one or more grid components that can be linked to the current record in the row.
Auto-expand first row
/documentation/pages/Guides/Mobile and Web Components/Grid/Grid Properties/Row Expander/autoexpandfirstrow.xml
Specify if the first row in the Grid should be automatically expanded when the Grid is loaded.
Row Properties
/documentation/pages/Guides/Mobile and Web Components/Grid/Grid Fields/Grid Field Properties/Row Properties/index.xml
Grid ro properties help alter the look and feel of grid rows.
Reporting::ReportContext.Expand Method
/documentation/pages/Ref/Api/Namespace/Reporting/ReportContext/Expand Method.xml
Expand chart members.
Row Number
/documentation/pages/Guides/Mobile and Web Components/UX/Controls/Defined Controls/Row Number.xml
Insert a field in a Repeating Section to show the row number of the current row.
Row Labels
/documentation/pages/Guides/Mobile and Web Components/Grid/Grid Properties/Row Labels/index.xml
The row labels section contains propeties for showing row labels and suppressing repeated row labels.
Row Number
/documentation/pages/Guides/Mobile and Web Components/UX/Controls/Defined Controls/Row Number/index.xml
Insert a field in a Repeating Section to show the row number for the current row.
Row Separator
/documentation/pages/Guides/Mobile and Web Components/Grid/Grid Properties/Shading and Dividers/Row Separator.xml
The Row separator property defines whether there should be separating line between rows. The divider is more noticeable in some styles.
OnExpandRow Event
/documentation/pages/Guides/Mobile and Web Components/Grid/Code/Server-side Events/OnExpandRow.xml

This event fires when the user clicks the icon to expand a row in the Grid.