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WPF-复选框组合框-是否选择绑定?

checkbox binding templates wpf

Sonny Boy · 技术社区 · 14 年前

我已经实现了一个复选框组合框,在GUI中看起来很不错,但在功能性方式中使用它时遇到了问题。

我遇到的主要问题是弄清楚哪些箱子是真的被检查过的。在运行时,ComboBox.SelectedItem工作正常,但是如果我遍历所有项,它们总是返回IsSelected==false。

有什么想法吗?

这是我的xaml:

<ComboBox Name="cboParam3" Grid.Row="0" Grid.Column="5" SelectedValuePath="Key" KeyDown="headerBar_KeyDown">
   <ComboBox.ItemTemplate>
      <DataTemplate>
         <StackPanel Orientation="Horizontal">
            <CheckBox IsChecked="{Binding Path=IsSelected}" VerticalAlignment="Center" Margin="0,0,4,0" />
            <TextBlock Text="{Binding Value}" VerticalAlignment="Center"/>
         </StackPanel>
      </DataTemplate>
   </ComboBox.ItemTemplate>
</ComboBox>

下面是我最初填充组合框的代码:

Dictionary<int, string> codes = CodeCache.CodeLookup<DACaseCategoryCode>();
List<MultipleComboItem> items = new List<MultipleComboItem>();

codes.ToList().ForEach(t =>
{
   MultipleComboItem item = new MultipleComboItem();

   item.Key = t.Key;
   item.Value = t.Value;
   item.IsSelected = false;

   items.Add(item);
});

this.lblParam3.Content = "Case Category:";
this.cboParam3.ItemsSource = items;

我还需要加入其他的东西来让它发挥作用吗?

谢谢,
桑尼

附言 MultipleComboItem 只是一个有三个性质的简单结构。没什么奇怪的事发生。

4 回复 | 直到 14 年前

Scott 14 年前

编辑:

我编写了一个快速测试应用程序,绑定似乎可以使用以下方法正常工作(但是,选中复选框不会设置组合框的SelectedItem属性):

<Window x:Class="TestApp11.MainWindow" 
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
  xmlns:l="clr-namespace:TestApp11"
  Title="Window1" >
    <Window.Resources>
    </Window.Resources>
    <Grid Background="Black">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="Auto" />
        </Grid.ColumnDefinitions>
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto" />
            <RowDefinition Height="Auto" />
        </Grid.RowDefinitions>
        <ComboBox Name="cboParam3" Grid.Row="0" Grid.Column="0">
            <ComboBox.ItemTemplate>
                <DataTemplate>
                    <StackPanel Orientation="Horizontal">
                        <CheckBox IsChecked="{Binding Path=Select}" VerticalAlignment="Center" Margin="0,0,4,0" />
                        <TextBlock Text="{Binding Name}" VerticalAlignment="Center"/>
                    </StackPanel>
                </DataTemplate>
            </ComboBox.ItemTemplate>
            </ComboBox>
        <Button Grid.Row="1" Content="Click Me For Break Point" Click="Button_Click"></Button>
    </Grid>
</Window>


using System.Collections.ObjectModel;
using System.Windows;

namespace TestApp11
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
    public ObservableCollection<MCI> MCIList { get; set; }
    public MainWindow()
    {
        InitializeComponent();
        this.MCIList = new ObservableCollection<MCI>();
        this.cboParam3.ItemsSource = this.MCIList;

        this.MCIList.Add(new MCI());
        this.MCIList.Add(new MCI());
        this.MCIList.Add(new MCI());
    }

    private void Button_Click(object sender, RoutedEventArgs e)
    {

    }

}

public class MCI
{
    public bool Select { get; set; }
    public string Name { get; set; }
    public MCI()
    {
        this.Name = "Bob";
        this.Select = false;
    }
}
}

你做的和我上面说的有什么不同吗?

DaveShaw Thishin 13 年前

<ComboBox Name="identifiercombo" Text="{Binding SelectedIdentifier, UpdateSourceTrigger=PropertyChanged}"  ItemsSource="{Binding IdentifierCollection}"  SelectedIndex="0" IsEditable="True" Grid.Row="3" Grid.Column="1" HorizontalAlignment="Stretch" Margin="10,5">
    <ComboBox.ItemTemplate>
        <DataTemplate>
            <StackPanel Orientation="Horizontal">
                <CheckBox Click="CheckBox_Click" Content="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=Content,UpdateSourceTrigger=PropertyChanged}" VerticalAlignment="Center"/>                            
            </StackPanel>
        </DataTemplate>
    </ComboBox.ItemTemplate>
</ComboBox>

Vladimir Dorokhov 14 年前

ComboBox.SelectedItem工作正常

好的,你可以选择多个目标。

如果我遍历所有项,它们总是返回IsSelected==false。

这是因为您已经绑定了IsChecked=“{Binding Path=IsSelected}”,如果选中打开的组合框列表中的复选框并再次遍历这些项,则可以找到IsSelected==true的项。

所以,如果不选中复选框,就找不到IsSelected==true。

你一定感觉不一样 挑选出来的 组合框项和 选中的 显示项目的复选框。

Rashed Bhatti 11 年前

我需要创建一个由复选框组成的自定义组合框,以显示供用户选择的日历月列表。此应用程序允许用户选择月份,无论何时选择或取消选择月份,都会更新列表框。我遍历组合框的itemsource observate集合,以确定选中的月份。我可能可以使用LINQ来查询集合,而不是手动遍历可观察集合,但那是另一天的事了。如果您想测试这个,只需创建一个名为CustomComboBox的新wpf应用程序(在C中),然后将xaml和C复制并粘贴到您的应用程序中:

<Window x:Class="CustomComboBox.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525">
    <Window.Resources>

    </Window.Resources>
    <Grid>      
        <Grid>
            <Grid.RowDefinitions>
                <RowDefinition Height="30" />
                <RowDefinition Height="30"/>
                <RowDefinition Height="Auto"/>
            </Grid.RowDefinitions>
            <Grid.ColumnDefinitions>
                <ColumnDefinition />
                <ColumnDefinition />            
            </Grid.ColumnDefinitions>
            <Label Grid.Column="0" Grid.Row="0" Content="Select the months:" />
            <Label Grid.Column="1" Grid.Row="1" Content="Months selected:" />
            <ComboBox x:Name="ComboBoxMonths" Grid.Column="0" Grid.Row="1">
                <ComboBox.ItemTemplate>
                    <DataTemplate>
                        <StackPanel Orientation="Horizontal">
                            <CheckBox IsChecked="{Binding Path=monthSelected}" VerticalAlignment="Center" Margin="0,0,4,0" Checked="CheckBox_Checked" Unchecked="CheckBox_Unchecked" />
                            <TextBlock Text="{Binding monthName}" VerticalAlignment="Center"/>
                        </StackPanel>
                    </DataTemplate>
                </ComboBox.ItemTemplate>
            </ComboBox>
            <ListBox x:Name="ListBoxMonthsChecked" Grid.Column="1" Grid.Row="2">
                <ListBox.ItemTemplate>
                    <DataTemplate>
                        <TextBlock Text="{Binding monthName}" VerticalAlignment="Center"/>
                    </DataTemplate>
                </ListBox.ItemTemplate>
            </ListBox>
        </Grid>       
    </Grid>

</Window>

c代码:

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.ComponentModel;
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.Navigation;
using System.Windows.Shapes;

namespace CustomComboBox
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public static ObservableCollection<Month> monthList = new ObservableCollection<Month>();
        public static ObservableCollection<Month> monthsChecked = new ObservableCollection<Month>();

        public MainWindow()
        {
            InitializeComponent();

            this.ComboBoxMonths.ItemsSource = monthList;
            this.ListBoxMonthsChecked.ItemsSource = monthsChecked;

            //add Months to the ComboBoxMonths
            monthList.Add(new Month() { monthSelected = false, monthName = "January", monthNumber = 01 });
            monthList.Add(new Month() { monthSelected = false, monthName = "February", monthNumber = 02 });
            monthList.Add(new Month() { monthSelected = false, monthName = "March", monthNumber = 03 });            
            monthList.Add(new Month() { monthSelected = false, monthName = "April", monthNumber = 04 });
            monthList.Add(new Month() { monthSelected = false, monthName = "May", monthNumber = 05 });
            monthList.Add(new Month() { monthSelected = false, monthName = "June", monthNumber = 06 });
            monthList.Add(new Month() { monthSelected = false, monthName = "July", monthNumber = 07 });
            monthList.Add(new Month() { monthSelected = false, monthName = "August", monthNumber = 08 });
            monthList.Add(new Month() { monthSelected = false, monthName = "September", monthNumber = 09 });
            monthList.Add(new Month() { monthSelected = false, monthName = "October", monthNumber = 10 });
            monthList.Add(new Month() { monthSelected = false, monthName = "November", monthNumber = 11 });
            monthList.Add(new Month() { monthSelected = false, monthName = "December", monthNumber = 12 });
        }

        public class Month
        {
            public string monthName { get; set; } 
            public int monthNumber { get; set; } 

            private bool _monthSelected;
            public bool monthSelected //the checkbox is bound to this
            {
                get
                {
                    return _monthSelected;
                }
                set
                {
                    if (value != this._monthSelected)
                    {
                        _monthSelected = value;                        
                    }
                }
            }

        }

        private void CheckBox_Checked(object sender, RoutedEventArgs e)
        {
            monthsChecked.Clear();
            foreach (Month m in monthList)
            {
                if (m.monthSelected == true)
                {                    
                    monthsChecked.Add(m);
                }
            }            
        }

        private void CheckBox_UnChecked(object sender, RoutedEventArgs e)
        {
            monthsChecked.Clear();
            foreach (Month m in monthList)
            {
                if (m.monthSelected == true)
                {
                    monthsChecked.Add(m);
                }
            }
        }

    }
}