Merge Cells in WPF DataGrid

Question

I want to create a WPF datagrid that spans over multiple rows in one column. Like this:

+-------+----------------+
| Name  | Attributes     |
+-------+----------------+
|       | Horse Power    |
| BMW   +----------------+
|       | Color          |
+-------+----------------+
|       | Weight         |
| Ford  +----------------+
|       | Color          |
+-------+----------------+

How can the following code be changed to get it done?

<DataGrid AutoGenerateColumns="False">
     <DataGrid.Columns>
          <DataGridTextColumn Header="Name" />
          <DataGridTextColumn Header="Attributes" />
     </DataGrid.Columns>
</DataGrid>

Answer 1

Try use DataGridTemplateColumn. I created sample test class for databinding

public class Test
{

    public Test(string name, string attribute1, string attribute2)
    {
        Name = name;
        Attributes = new Attribute(attribute1, attribute2);
    }

    public string Name { get; set; }
    public Attribute Attributes { get; set; }
}

public class Attribute
{

    public Attribute(string attribute1, string attribute2)
    {
        Attribute1 = attribute1;
        Attribute2 = attribute2;
    }

    public string Attribute1 { get; set; }
    public string Attribute2 { get; set; }
}

And a datagrid in xaml

<DataGrid AutoGenerateColumns="False"  Name="dataGrid1" ItemsSource="{Binding}">
        <DataGrid.Columns>
            <DataGridTemplateColumn Header="Name"  >
                <DataGridTemplateColumn.CellTemplate>
                    <DataTemplate>
                        <Grid>
                            <TextBlock Text="{Binding Path=Name}"  VerticalAlignment="Center" Margin="3,3,3,3"/>
                        </Grid>
                    </DataTemplate>
                </DataGridTemplateColumn.CellTemplate>
            </DataGridTemplateColumn>
            <DataGridTemplateColumn Header="Attributes"  >
                <DataGridTemplateColumn.CellTemplate>
                    <DataTemplate >
                        <Grid>
                            <Grid.RowDefinitions>
                                <RowDefinition Height="50*"/>
                                <RowDefinition />
                                <RowDefinition Height="50*"/>
                            </Grid.RowDefinitions>
                            <TextBlock Grid.Row="0" Text="{Binding Path=Attributes.Attribute1}" VerticalAlignment="Center" Margin="3,3,3,3"/>
                            <Line Grid.Row="1" Stroke="Black" Stretch="Fill" X2="1" VerticalAlignment="Center"/>
                            <TextBlock Grid.Row="2" Text="{Binding Path=Attributes.Attribute2}"  VerticalAlignment="Center" Margin="3,3,3,3"/>
                        </Grid>
                    </DataTemplate>
                </DataGridTemplateColumn.CellTemplate>
            </DataGridTemplateColumn>
        </DataGrid.Columns>
    </DataGrid>

And fill it in code-behind

List<Test> list = new List<Test>();
//populate list with your data here
dataGrid1.DataContext = list;

Answer 2

I managed to implement a solution that does what you want with three levels of grouping with one small issue, in that that the Group Headers scroll horizontally with the data.

    <Style x:Key="GroupItemStyle" TargetType="{x:Type GroupItem}">
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type GroupItem}">
                        <StackPanel Orientation="Horizontal" >
                            <Border BorderThickness="0">
                                <Grid HorizontalAlignment="Center" VerticalAlignment="Center">
                                    <Grid.ColumnDefinitions>
                                        <ColumnDefinition Width="Auto"/>
                                        <ColumnDefinition Width="Auto"/>
                                    </Grid.ColumnDefinitions>

                                    <Border BorderThickness="1" MinWidth="150">
                                        <Grid HorizontalAlignment="Center" VerticalAlignment="Center">
                                            <ContentPresenter Content="{Binding Name}" >
                                            </ContentPresenter>
                                        </Grid>

                                    </Border>
                                    <Border BorderThickness="0" Grid.Column="1">
                                        <Grid HorizontalAlignment="Center" VerticalAlignment="Center">
                                            <ItemsPresenter/>
                                        </Grid>
                                    </Border>
                                </Grid>
                            </Border>
                        </StackPanel>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>

And the Grid:

            <DataGrid ItemsSource="{Binding GroupedData}" AutoGenerateColumns="False" MinRowHeight="25" CanUserAddRows="False" CanUserDeleteRows="False">
                <DataGrid.GroupStyle>
                    <!-- First Group -->
                    <GroupStyle ContainerStyle="{StaticResource GroupItemStyle}">
                        <GroupStyle.Panel>
                            <ItemsPanelTemplate>
                                <DataGridRowsPresenter/>
                            </ItemsPanelTemplate>
                        </GroupStyle.Panel>
                    </GroupStyle>

                    <!-- Second Group -->
                    <GroupStyle ContainerStyle="{StaticResource GroupItemStyle}">
                        <GroupStyle.Panel>
                            <ItemsPanelTemplate>
                                <DataGridRowsPresenter/>
                            </ItemsPanelTemplate>
                        </GroupStyle.Panel>

                    </GroupStyle>

                    <!-- Third Group -->
                    <GroupStyle ContainerStyle="{StaticResource GroupItemStyle}">
                        <GroupStyle.Panel>
                            <ItemsPanelTemplate>
                                <DataGridRowsPresenter/>
                            </ItemsPanelTemplate>
                        </GroupStyle.Panel>
                    </GroupStyle>
                </DataGrid.GroupStyle>
                <DataGrid.Columns>
        ...
                </DataGrid.Columns>
            </DataGrid>