Question

我正在研究wpf MVVM应用程序，有2个控件组合框和Datagrid。根据在Combobox中选择的值，应过滤Datagrid项目源。这工作正常。下一个要求是，如果Combobox中的项目在Datagrid中至少有一个过滤值，则Combobox中的项目文本应设置为粗体。任何人都可以建议以这种要求的优化方式实施

Answer 1

使用Attached创建ItemsSource of DataGrid属性以获取PropertyChangedCallback()。
将此属性应用于用于显示查找项的控件。可以TextBlock在ComboBox中显示国家/地区名称。
您将通过DataGrid.ItemsSource和TextBlock收到回叫，只需遍历列表，然后将FontWeight设置为Bold。

示例：

<强> Window2.xaml

<Window x:Class="WpfAdvanced.Window2"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:cc="clr-namespace:WpfAdvanced"
        xmlns:local="clr-namespace:WpfAdvanced"
        Title="Window2" Height="300" Width="300">

    <StackPanel x:Name="Grd">
        <Button Content="Add" HorizontalAlignment="Left" VerticalAlignment="Top" Width="75" Click="Button_Click_1"/>
        <ComboBox x:Name="Cmb">
            <ComboBox.ItemTemplate>
                <DataTemplate>
                    <TextBlock Text="{Binding Name}" local:Window2.ItemsSource="{Binding ItemsSource, ElementName=Dgrd}"/>
                </DataTemplate>
            </ComboBox.ItemTemplate>
        </ComboBox>

        <DataGrid x:Name="Dgrd">            
        </DataGrid>

    </StackPanel>

</Window>

<强> Window2.xaml.cs

using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;

namespace WpfAdvanced
{
    /// <summary>
    /// Interaction logic for Window2.xaml
    /// </summary>
    public partial class Window2 : Window
    {
        DataGrid b = new DataGrid();
        ArrayList countries = new ArrayList();
        ArrayList lookupCountries = new ArrayList();



        public static ArrayList GetItemsSource(DependencyObject obj)
        {
            return (ArrayList)obj.GetValue(ItemsSourceProperty);
        }

        public static void SetItemsSource(DependencyObject obj, ArrayList value)
        {
            obj.SetValue(ItemsSourceProperty, value);
        }

        // Using a DependencyProperty as the backing store for ItemsSource.  This enables animation, styling, binding, etc...
        public static readonly DependencyProperty ItemsSourceProperty =
            DependencyProperty.RegisterAttached("ItemsSource", typeof(ArrayList), typeof(Window2), new PropertyMetadata(null, new PropertyChangedCallback(myCallback)));

        private static void myCallback(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            TextBlock tb = (TextBlock)d;
            ArrayList v = (ArrayList)e.NewValue;
            bool found = false;
            for (int i = 0; i < v.Count; ++i)
            {
                dynamic o = v[i];
                if (o.Name == tb.Text)
                {
                    found = true;
                    break;
                }
            }
            if (found)
                tb.FontWeight = FontWeights.ExtraBold;
        }



        public Window2()
        {
            InitializeComponent();

            dynamic o1 = new { Name = "UK", Capital = "London" };            
            countries.Add(o1);
            dynamic o2 = new { Name = "USA", Capital = "New York" };
            countries.Add(o2);
            dynamic o3 = new { Name = "INDIA", Capital = "New Delhi" };
            countries.Add(o3);
            dynamic o4 = new { Name = "INDIA", Capital = "Shimla" };
            countries.Add(o4);

            Dgrd.ItemsSource = countries;

            dynamic c1 = new { Name = "UK" };
            lookupCountries.Add(c1);
            dynamic c2 = new { Name = "INDIA" };
            lookupCountries.Add(c2);
            dynamic c3 = new { Name = "SRILANKA" };
            lookupCountries.Add(c3);

            Cmb.ItemsSource = lookupCountries;
        }

        private void Button_Click_1(object sender, RoutedEventArgs e)
        {
            CollectionViewSource.GetDefaultView(Dgrd.ItemsSource).Filter = grdFilter;
        }

        private bool grdFilter(dynamic obj)
        {
            dynamic i = Cmb.SelectedItem;

            return (obj.Name == i.Name);
        }
    }   
}

如果Datagrid中存在相关记录，则下拉项应为粗体

1 个答案: