Question

我有一个DataGrid，它们的行非常快地更新了。每行都有一个右键单击事件，如果单击该事件，则应将所选行添加到另一个dataGrid。问题是当用户选择一行以添加到另一个列表时由于更新了所选行，他无法添加，因此用户应一次又一次选择该行。我的代码是这样的

       <DataGrid SelectionMode="Single" CanUserAddRows="False"CanUserDeleteRows="False"  >

            <DataGrid.Columns>
                <DataGridTextColumn   Header="Data1"  Binding="{Binding Path=Data1}"></DataGridTextColumn>
                <DataGridTextColumn   Header="Data2"  Binding="{Binding Path=Data2}"></DataGridTextColumn>
                <DataGridTextColumn   Header="Data3"  Binding="{Binding Path=Data3}"></DataGridTextColumn>
                <DataGridTextColumn   Header="Data4" Binding="{Binding Path=Data4}"></DataGridTextColumn>
                <DataGridTextColumn   Header="Data5" Binding="{Binding Path=Data5}"></DataGridTextColumn>
                <DataGridTextColumn   Header="Data6" Binding="{Binding Path=Data6}"></DataGridTextColumn>

            </DataGrid.Columns>

            <DataGrid.ContextMenu>
                <ContextMenu HorizontalContentAlignment="Right" FlowDirection="RightToLeft">

                    <MenuItem Name="addToBlackListMnuBtn" Header="Add to Black List" Click="addToBlackListMnuBtn_Click" FontWeight="Black"/>
                    <MenuItem Name="addtoReportedListMnuBtn" Header="Add to Reported List"  Click="addtoReportedListMnuBtn_Click" FontWeight="Black"/>

                </ContextMenu>
            </DataGrid.ContextMenu>

        </DataGrid>

当我想从contexMenu中单击“ addtoReportedListMnuBtn”时，我应该尝试几次以完成其事件。通常在下面的代码中显示messageBox

private void addtoReportedListMnuBtn_Click(object sender, RoutedEventArgs e)//add to reported list
    {
        ObjClass en = (ObjClass)ActiveSignalDataGrid.SelectedItem;
        if(en!=null)
        {
            ReportSignalsListQ.Data = en; // add to queue for adding 
        }else
        {
            MessageBox.Show("Please select again");
        }
    }

Answer 1

我想说，DataGrid在您的情况下对ContextMenu是错误的地方。将您的ContextMenu放入窗口的资源中，并用于DataGridCell。

<Window.Resources>
    <ContextMenu x:Key="contMen" HorizontalContentAlignment="Right" FlowDirection="RightToLeft">
        <MenuItem Name="addToBlackListMnuBtn" Header="Add to Black List" Click="addToBlackListMnuBtn_Click" FontWeight="Black"/>
        <MenuItem Name="addtoReportedListMnuBtn" Header="Add to Reported List"  Click="addtoReportedListMnuBtn_Click" FontWeight="Black"/>
    </ContextMenu>
</Window.Resources>


<DataGrid.Resources>
    <Style TargetType="DataGridCell">
        <Setter Property="ContextMenu" Value="{StaticResource contMen}"/>                        
    </Style>
</DataGrid.Resources>

private void addtoReportedListMnuBtn_Click(object sender, RoutedEventArgs e)//add to reported list
{
    var en = (((sender as MenuItem).Parent as ContextMenu).PlacementTarget as DataGridCell).DataContext as ObjClass;
    if (en != null)
    {
        ReportSignalsListQ.Data = en; // add to queue for adding 
    }
    else
    {
        MessageBox.Show("Please select again");
    }
}

Answer 2

当您的ItemSource更新时，您的SelectedItem的{{1}}被清除。因此，您可以将DataGrid事件添加到SelectionChanged中，然后需要将DataGrid分配给后面代码中的局部变量，然后将局部变量添加到第二个{{1 }}。

DataGrid中的选定行已丢失

2 个答案: