small adds

Author: didiyordanova

controls/datagrid/theming-and-styles/style-selectors.md

@@ -23,6 +23,15 @@ You can set a distinct style to a specific cell in a given column based on custo
 ## Row Background Style Selector
 
 You can set a different style on a row, an alternate row, and on row details based on custom style-selection logic by using the `RowBackgroundStyleSelector` (`IStyleSelector`) property.
+To apply a `RowBackgroundStyleSelector` follow these steps:
+1. Create a custom class that inherits from `IStyleSelector`. 
+1. Implement the `SelectStyle` method.
+1. The object item of the `SelectStyle` method is of type `DataGridRowInfo`. The `DataGridRowInfo` represents a class that provides information for each row in DataGrid and exposes the follwoing properties:
+	
+	* `Item` (`object`)—Gets the business object associated with the row.
+	* `IsRowDetails` (`bool`)`—Gets a value that specifies whether the row is RowDetail.
+	* `IsAlternate` (`bool`)—Gets a value that specifies whether the row is an alternate one.
+
 
 > For the DataGrid Row Background Style Selector example, go to the [SDKBrowser Demo Application]({%slug sdkbrowser-app%}) and navigate to the **DataGrid > Styling** category.