ES-975464 - Resolve the ReadMe issue in this sample repository

Author: SreemonPremkumarM

README.md

@@ -1,2 +1,41 @@
-# How to customize the tooltip using DataTemplate in winui datagrid?
-This repository explains how to customize the tooltip using DataTemplate in winui datagrid.
+# How to customize the tooltip using DataTemplate in WinUI DataGrid
+
+This repository explains how to customize the tooltip using DataTemplate in [WinUI DataGrid](https://www.syncfusion.com/winui-controls/datagrid) (SfDataGrid).
+
+You can customize the appearance of the ToolTip for particular column by setting `GridColumn.ToolTipTemplate`. And you can also customize the appearance of header ToolTip for particular column by [GridColumn.HeaderToolTipTemplate](https://help.syncfusion.com/cr/winui/Syncfusion.UI.Xaml.Grids.GridColumnBase.html#Syncfusion_UI_Xaml_Grids_GridColumnBase_HeaderToolTipTemplate) property.
+
+#### XAML
+
+``` xml
+<Application.Resources>
+    <local:StringToImageConverter x:Key="imageConverter" />        
+    <DataTemplate x:Key="templateToolTip">
+        <Image Height="100" Width="100" Source="{Binding CustomerID,Converter={StaticResource imageConverter}}" />
+    </DataTemplate>
+</Application.Resources>
+
+
+<dataGrid:SfDataGrid.Columns>
+    <dataGrid:GridNumericColumn HeaderText="Order ID"  ShowToolTip="True" MappingName="OrderID" />
+    <dataGrid:GridTextColumn HeaderText="Customer ID" ToolTipTemplate="{StaticResource templateToolTip}" ShowToolTip="True" MappingName="CustomerID" />
+</dataGrid:SfDataGrid.Columns>
+```
+
+#### C#
+
+``` csharp
+public class StringToImageConverter : IValueConverter
+{
+    public object Convert(object value, Type targetType, object parameter, string language)
+    {
+        string imagename = value.ToString();
+        return "Assets/" + imagename + @".png";
+    }
+    public object ConvertBack(object value, Type targetType, object parameter, string language)
+    {
+        return value;
+    }
+}
+```
+
+![customize the tooltip](customize_the_tooltip.png)