How to restrict the expand and collapse the groups when click on the caption row in WPF DataGrid (SfDataGrid)?

this.sfDataGrid.GroupCollapsing += SfDataGrid_GroupCollapsing;
this.sfDataGrid.GroupExpanding += SfDataGrid_GroupExpanding;
this.sfDataGrid.SelectionChanging += SfDataGrid_SelectionChanging;private void SfDataGrid_SelectionChanging(object sender, GridSelectionChangingEventArgs e)
{
    var visualcontainer = this.sfDataGrid.GetVisualContainer();
    var point = Mouse.GetPosition(visualcontainer);
    //Here you can get the row and column index based on the pointer position by using PointToCellRowColumnIndex() method 
    var rowColumnIndex = visualcontainer.PointToCellRowColumnIndex(point);
    //When the rowindex is zero , the row will be header row  
    if (!rowColumnIndex.IsEmpty)
    {
        if (rowColumnIndex.ColumnIndex == 0)
            e.Cancel = true;
    }
}
 
private void SfDataGrid_GroupExpanding(object sender, GroupChangingEventArgs e)
{
    var visualcontainer = this.sfDataGrid.GetVisualContainer();
    var point = Mouse.GetPosition(visualcontainer);
    //Here you can get the row and column index based on the pointer position by using PointToCellRowColumnIndex() method
    var rowColumnIndex = visualcontainer.PointToCellRowColumnIndex(point);
    //When the rowindex is zero , the row will be header row 
    if (!rowColumnIndex.IsEmpty)
    {               
        if (rowColumnIndex.ColumnIndex > 0)
            e.Cancel = true;
    }
}
 
private void SfDataGrid_GroupCollapsing(object sender, GroupChangingEventArgs e)
{
    var visualcontainer = this.sfDataGrid.GetVisualContainer();
    var point = Mouse.GetPosition(visualcontainer);
    //Here you can get the row and column index based on the pointer position by using PointToCellRowColumnIndex() method
    var rowColumnIndex = visualcontainer.PointToCellRowColumnIndex(point);
    //When the rowindex is zero , the row will be header row 
    if (!rowColumnIndex.IsEmpty)
    {
        if (rowColumnIndex.ColumnIndex > 0)
            e.Cancel = true;
    }
}