c# WPF -不能在DataGridCheckBoxColumn中勾选/取消勾选复选框

我在XAML中初始化DataGrid，但由于列根据输入数据而变化，因此在代码中生成了列。但是，当生成DataGridCheckBoxColumn时，我无法选中/取消选中此列任何一行中的单个复选框。其中一些是根据bool "checkFlag"的值进行检查/未检查的

DataGridCheckBoxColumn checkColumn = new DataGridCheckBoxColumn();
checkColumn.Header = "Save";
checkColumn.Binding = new Binding("checkFlag");
checkColumn.MinWidth = 50;
vysledkyDataGrid.Columns.Add(checkColumn);
<DataGrid AutoGenerateColumns="false" 
          Margin="20,247,25,94" 
          Name="vysledkyDataGrid"
          IsEnabled="True" 
          CanUserReorderColumns="False" 
          CanUserResizeColumns="True" 
          CanUserSortColumns="False" 
          HorizontalGridLinesBrush="DarkGray"              
          VerticalGridLinesBrush="DarkGray" 
          ClipboardCopyMode="None" 
          IsReadOnly="True">
        <DataGrid.ColumnHeaderStyle>
            <Style TargetType="{x:Type DataGridColumnHeader}">
                <Setter Property="HorizontalAlignment" Value="Stretch" />
                <Setter Property="HorizontalContentAlignment" Value="Center" />
            </Style>
        </DataGrid.ColumnHeaderStyle>
        <DataGrid.CellStyle>
            <Style TargetType="DataGridCell">
                <Setter Property="Block.TextAlignment" Value="Right"/>
            </Style>
        </DataGrid.CellStyle>
    </DataGrid>