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c#wpfdata-bindingdatagridtextcolumncompositecollection

DateGridTextColumn disable null values


I have a DataGridTextColumn binded with a CompositeCollection of 4 ObservableCollection

One of the DataGridTextColumn, binded like this:

<DataGrid x:Name="DonneesBrutes" IsReadOnly="True" ItemsSource="{Binding Path=.cmpc}" Margin="10,65,0,0" AutoGenerateColumns="False" EnableRowVirtualization="True" RowDetailsVisibilityMode="VisibleWhenSelected">
            <DataGrid.Columns>
                <DataGridTextColumn x:Name="Ligne" Width="*"  Binding="{Binding Path=.Remarque}" Header="Ligne" IsReadOnly="True"></DataGridTextColumn>

Where cmpc is my CompositeCollection and Where Ligne mustn't get a null value. Problem, I takes a lot of null values like in this screen shot: http://www.zimagez.com/zimage/compositecollection.php How can I ignore every lines where it has a null value? Is something like IsNullAble = false exists for a DataGridTextColumn?


Solution

  • Here's a simple example (Tested). You will not see the second row because of the trigger. I'm using int values so I'm comparing to 20 in trigger. in your case, use x:Null. You can use the same technique with yours.

    XAML :

    <Window x:Class="DataGridTest.MainWindow"
            xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
            xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
            xmlns:dataGridTest="clr-namespace:DataGridTest"
            Title="MainWindow" Height="350" Width="525">
        <DataGrid AutoGenerateColumns="True">
        <DataGrid.RowStyle>
            <Style TargetType="{x:Type DataGridRow}">
                <Style.Triggers>
                    <DataTrigger Binding="{Binding X}" Value="20">
                        <Setter Property="Visibility" Value="Collapsed"></Setter>
                    </DataTrigger>
                </Style.Triggers>
            </Style>
        </DataGrid.RowStyle>
    
            <DataGrid.Items>
                <dataGridTest:Test X="10" Y="5" />
                <dataGridTest:Test X="20" Y="10" />
            </DataGrid.Items>
            <DataGrid.Columns>
                <DataGridTextColumn Binding="{Binding X}" />
                <DataGridTextColumn Binding="{Binding Y}" />
            </DataGrid.Columns>
        </DataGrid>
    </Window>
    

    Code behind:

    namespace DataGridTest
    {
        /// <summary>
        /// Interaction logic for MainWindow.xaml
        /// </summary>
        public partial class MainWindow : Window
        {
            public MainWindow()
            {
                InitializeComponent();
            }
        }
    
        public class Test
        {
            public int X { get; set; }
            public int Y { get; set; }
        }
    }