从组合框中筛选dataGridComboBox列

本文关键字：dataGridComboBox 筛选组合 | 更新日期: 2023-09-27 18:19:48

首先我在组合框列中选择一个供应商，然后只有来自该供应商的引用才能填充dataGridComboBox列。

我以为我知道怎么做，但显然少了一些东西。我没有任何错误，但我的dataGridComboBox列仍然为空。

查看

<ComboBox x:Name="supplierComboBox"
                      Margin="5" 
                      ItemsSource="{Binding Collection, Source={StaticResource supplier}}" 
                      DisplayMemberPath="supplier"
                      SelectedItem="{Binding Supplier,UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}" 
                      SelectedValuePath="idfoodSupplier"
                      Text="{Binding SupplierText, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"
                      Width="160"/>
<DataGrid x:Name="dataGridInvoice" 
                      ItemsSource="{Binding Collection}" 
                      AutoGenerateColumns="False">
                <DataGrid.Columns>
                    <DataGridComboBoxColumn Header="Ref Supplier"
                                            ItemsSource="{Binding Reference, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
                                            DisplayMemberPath="refsup" 
                                            SelectedValueBinding="{Binding refSup}" 
                                            SelectedValuePath="refsup"
                                            Width="*"/>  
                </DataGrid.Columns>
            </DataGrid>

ViewModel

public class InvoiceViewModel : ViewModelBase
    {

        public Context ctx = new Context();
        Invoice invoice;
        public InvoiceViewModel()
        {
            Collection = new ObservableCollection<PreInvoice>();
        }
        private ObservableCollection<PreInvoice> collection;
        public ObservableCollection<PreInvoice> Collection
        {
            get
            {
                return collection;
            }
            set
            {
                collection = value;
                OnPropertyChanged("Collection");
            }
        }
        private foodSupplier _supplier;
        public foodSupplier Supplier
        {
            get
            {
                return _supplier;
            }
            set
            {
                _supplier = value;
                OnPropertyChanged("Supplier");
                Reference = new List<product>();
                Reference = (from p in ctx.products
                              where p.supplier == _supplier.idfoodSupplier
                              select p).ToList();
            }
        }
        private List<product> _reference;
        public List<product> Reference
        {
            get
            {
                return _reference;
            }
            set
            {
                _reference = value;
                OnPropertyChanged("Reference");
            }
        }

        public class PreInvoice : ViewModelBase
        {
            public string refSup {get; set;}

        }
    }

产品型号

public partial class product
{
    public int idproduct { get; set; }
    public Nullable<int> supplier { get; set; }
    public string refsup { get; set; }
    public string description { get; set; }
    public virtual foodSupplier foodSupplier { get; set; }
}

从组合框中筛选dataGridComboBox列

由于DataGridComboBoxColumn或任何其他支持的数据网格列不是数据网格可视化树的一部分，因此它们不会继承数据网格的DataContext。因为，它们不在视觉树中，所以任何使用RelativeSource获取DataContext的尝试都不会奏效。

解决方案-您可以创建一个代理元素来绑定窗口的数据上下文；使用该代理元素来绑定CCD_ 4的CCD_。例如：

<Window x:Class="WpfApplication10.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApplication10"
        mc:Ignorable="d"
        Title="MainWindow" Height="350" Width="525"
        d:DataContext="{d:DesignInstance local:Vm, IsDesignTimeCreatable=True}">
    <Grid>
        <Grid.Resources>
            <FrameworkElement x:Key="ProxyElement" DataContext="{Binding}"/>
        </Grid.Resources>
        <Grid.RowDefinitions>
            <RowDefinition Height="*" />
            <RowDefinition Height="*" />
        </Grid.RowDefinitions>
            <ComboBox x:Name="supplierComboBox"
                      Margin="5" 
                      ItemsSource="{Binding Collection, Source={StaticResource supplier}}" 
                      DisplayMemberPath="supplier"
                      SelectedItem="{Binding Supplier,UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}" 
                      SelectedValuePath="idfoodSupplier"
                      Text="{Binding SupplierText, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"
                      Width="160"/>
        <ContentControl Visibility="Collapsed" Content="{StaticResource ProxyElement}"></ContentControl>
        <DataGrid x:Name="dataGridInvoice" 
                  ItemsSource="{Binding Collection}" 
                  AutoGenerateColumns="False">
            <DataGrid.Columns>
             <DataGridComboBoxColumn Header="Ref Supplier"
                                            ItemsSource="{Binding DataContext.Reference, Source={StaticResource ProxyElement}}"
                                            DisplayMemberPath="refsup" 
                                            SelectedValueBinding="{Binding refSup}" 
                                            SelectedValuePath="refsup"
                                            Width="*"/>  
            </DataGrid.Columns>
            </DataGrid.Columns>
        </DataGrid>
    </Grid>
</Window>