Wpf 如何通过单击分组列表框的DataTemplate中的按钮从分组列表框中删除项目？_Wpf_Silverlight_Windows Store Apps_Windows Store

Wpf 如何通过单击分组列表框的DataTemplate中的按钮从分组列表框中删除项目？

wpf silverlight windows-store-apps

Wpf 如何通过单击分组列表框的DataTemplate中的按钮从分组列表框中删除项目？,wpf,silverlight,windows-store-apps,windows-store,Wpf,Silverlight,Windows Store Apps,Windows Store,我在使用MVVM开发一个小型Windows应用商店应用程序时遇到了一个难题。我想用ListBox显示《老大哥》第14季中的一份房客名单。根据设计，每个ListBoxItem中都应该有一个按钮。单击按钮时，应触发一个命令，该命令将从ListBox中删除ListBoxItem 下面是我目前的解决方案。它可以工作，但不是很令人满意，因为每当从列表框中删除一个项时，模型都需要过滤整个集合并刷新整个列表框，这会导致一些性能问题，特别是当原始集合非常庞大时 [主页.xaml] <Page x:

我在使用MVVM开发一个小型Windows应用商店应用程序时遇到了一个难题。我想用ListBox显示《老大哥》第14季中的一份房客名单。根据设计，每个ListBoxItem中都应该有一个按钮。单击按钮时，应触发一个命令，该命令将从ListBox中删除ListBoxItem

下面是我目前的解决方案。它可以工作，但不是很令人满意，因为每当从列表框中删除一个项时，模型都需要过滤整个集合并刷新整个列表框，这会导致一些性能问题，特别是当原始集合非常庞大时

[主页.xaml]

<Page
    x:Class="App1.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:App1"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d">

    <Page.Resources>
        <CollectionViewSource x:Name="groupInfo" IsSourceGrouped="true" ItemsPath="Items" />
        <local:BigBrotherModel x:Name="BBModel" />
        <DataTemplate x:Key="lvwItemTemp">
            <StackPanel>
                <Grid  Height="30">
                    <Grid.ColumnDefinitions>
                        <ColumnDefinition Width="40" />
                        <ColumnDefinition Width="100" />
                        <ColumnDefinition Width="100" />
                    </Grid.ColumnDefinitions>

                    <Button  Grid.Column="0" Padding="0" Foreground="Red" FontFamily="Segoe UI Symbol"
                                Command="{Binding DataContext.RemoveHouseGuestCommand, ElementName=lbxHouseGuests}" 
                                CommandParameter="{Binding}">&#xE221;</Button>
                    <TextBlock Grid.Column="1" Text="{Binding FirstName}" HorizontalAlignment="Stretch" />
                    <TextBlock Grid.Column="2" Text="{Binding LastName}" HorizontalAlignment="Stretch"  />
                </Grid>
            </StackPanel>
        </DataTemplate>
    </Page.Resources>


    <Grid Background="{StaticResource ApplicationPageBackgroundThemeBrush}">
        <ListBox x:Name="lbxHouseGuests" DataContext="{StaticResource BBModel}" ItemsSource="{Binding Source={StaticResource groupInfo}}" ItemTemplate="{StaticResource lvwItemTemp}" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
            <ListBox.GroupStyle>
                <GroupStyle>
                    <GroupStyle.HeaderTemplate>
                        <DataTemplate>
                            <Border BorderBrush="Red" BorderThickness="0" Background="DarkGray" HorizontalAlignment="Stretch">
                                <TextBlock Width="500" Text="{Binding Role}"/>
                            </Border>
                        </DataTemplate>
                    </GroupStyle.HeaderTemplate>
                </GroupStyle>
            </ListBox.GroupStyle>
        </ListBox>
    </Grid>
</Page>


；

[主页.cs]

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Windows.Input;
using Windows.Foundation;
using Windows.Foundation.Collections;
using System.Collections.ObjectModel;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Controls.Primitives;
using Windows.UI.Xaml.Data;
using Windows.UI.Xaml.Input;
using Windows.UI.Xaml.Media;
using Windows.UI.Xaml.Navigation;
using Windows.UI.Popups;
using System.Diagnostics;


namespace App1
{


    public class HouseGuest
    {
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public string Role { get; set; }
        public bool Deleted { get; set; }
    }

    public class BigBrotherModel
    {
        public ObservableCollection<HouseGuest> houseGuests { get; set; }
        public ListBox lbx { get; set; }
        public CollectionViewSource cvs { get; set; }

        public BigBrotherModel()
        {
            houseGuests = new ObservableCollection<HouseGuest>();
            houseGuests.Add(new HouseGuest() { FirstName = "Ian", LastName = "Terry", Role="Player" });
            houseGuests.Add(new HouseGuest() { FirstName = "Shane", LastName = "Meaney", Role = "Player" });
            houseGuests.Add(new HouseGuest() { FirstName = "Wil", LastName = "Heuser", Role = "Player" });
            houseGuests.Add(new HouseGuest() { FirstName = "Danielle", LastName = "Murphree", Role = "Player" });
            houseGuests.Add(new HouseGuest() { FirstName = "Jenn", LastName = "Arroyo", Role = "Player" });
            houseGuests.Add(new HouseGuest() { FirstName = "Jodi", LastName = "Rollins", Role = "Player" });
            houseGuests.Add(new HouseGuest() { FirstName = "Ashley", LastName = "Iocco", Role = "Player" });

            houseGuests.Add(new HouseGuest() { FirstName = "Britney", LastName = "Haynes", Role = "Coach" });
            houseGuests.Add(new HouseGuest() { FirstName = "Dan", LastName = "Gheesling", Role = "Coach"});
            houseGuests.Add(new HouseGuest() { FirstName = "Janelle", LastName = "Pierzina", Role = "Coach" });
            houseGuests.Add(new HouseGuest() { FirstName = "Mike", LastName = "Boogie", Role = "Coach"});


            RemoveHouseGuestCommand = new DelegateCommand(RemoveHouseGuest);
        }
        public ICommand RemoveHouseGuestCommand { get; set; }

        void RemoveHouseGuest(object param)
        {
            Debug.Assert(param is HouseGuest);
            (param as HouseGuest).Deleted = true;
            RefreshListBox();
        }

        object GetGroupedView()
        {
            var view = from hg in houseGuests
                       where hg.Deleted == false
                       group hg by hg.Role into g
                       orderby g.Key
                       select new { Role = g.Key, Items = g };
            return view;
        }

        public void RefreshListBox()
        {
            cvs.Source = GetGroupedView();
        }
    }

    public sealed partial class MainPage : Page
    {

        public MainPage()
        {
            this.InitializeComponent();
            BBModel.cvs = groupInfo;
            BBModel.lbx = lbxHouseGuests;

            BBModel.RefreshListBox();
        }
    }
}

使用系统；
使用System.Collections.Generic；
使用System.IO；
使用System.Linq；
使用System.Windows.Input；
使用Windows基金会；
使用Windows。
使用System.Collections.ObjectModel；
使用Windows.UI.Xaml；
使用Windows.UI.Xaml.Controls；
使用Windows.UI.Xaml.Controls.Primitives；
使用Windows.UI.Xaml.Data；
使用Windows.UI.Xaml.Input；
使用Windows.UI.Xaml.Media；
使用Windows.UI.Xaml.Navigation；
使用Windows.UI.Popups；
使用系统诊断；
名称空间App1
{
公务舱房客
{
公共字符串名{get；set；}
公共字符串LastName{get；set；}
公共字符串角色{get；set；}
公共bool已删除{get；set；}
}
公共类BigBrotherModel
{
公共可观察的集合房客{get；set；}
公共列表框lbx{get；set；}
public CollectionViewSource cvs{get；set；}
公共BigBrotherModel（）
{
客房客人=新的可观察收集（）；
添加（newhousegest（）{FirstName=“Ian”，LastName=“Terry”，Role=“Player”}）；
添加（newhousegest（）{FirstName=“Shane”，LastName=“Meaney”，Role=“Player”}）；
添加（newhousegest（）{FirstName=“Wil”，LastName=“Heuser”，Role=“Player”}）；
添加（newhousegest（）{FirstName=“Danielle”，LastName=“Murphree”，Role=“Player”}）；
添加（newhousegest（）{FirstName=“Jenn”，LastName=“Arroyo”，Role=“Player”}）；
添加（newhousegest（）{FirstName=“Jodi”，LastName=“Rollins”，Role=“Player”}）；
添加（newhousegest（）{FirstName=“Ashley”，LastName=“Iocco”，Role=“Player”}）；
添加（newhousegest（）{FirstName=“Britney”，LastName=“Haynes”，Role=“Coach”}）；
添加（newhousegest（）{FirstName=“Dan”，LastName=“Gheesling”，Role=“Coach”}）；
添加（newhousegest（）{FirstName=“Janelle”，LastName=“Pierzina”，Role=“Coach”}）；
添加（newhousegest（）{FirstName=“Mike”，LastName=“Boogie”，Role=“Coach”}）；
RemoveHouseGuestCommand=新的DelegateCommand（RemoveHouseGuest）；
}
public ICommand RemoveHouseGuestCommand{get；set；}
void RemoveHouseGuest（对象参数）
{
Assert（param是housegest）；
（参数为客房客人）。已删除=真；
刷新列表框（）；
}
对象GetGroupedView（）
{
var view=来自客房内的hg
其中hg.Deleted==false
将汞按汞分组。角色分为g
orderby g.Key
选择新{Role=g.Key，Items=g}；
返回视图；
}
公共空刷新列表框（）
{
cvs.Source=GetGroupedView（）；
}
}
公共密封部分类主页面：第页
{
公共主页（）
{
this.InitializeComponent（）；
BBModel.cvs=groupInfo；
BBModel.lbx=lbxHouseGuests；
BBModel.RefreshListBox（）；
}
}
}

我的问题是：有没有一种方法可以从分组的ListBox中删除ListBoxItem，而不需要使用MVVM刷新整个ListBox？我真的被困在这里了。如有任何建议，将不胜感激。非常感谢

[编辑] 谢谢Nate的建议，我在MainPage.cs中重写了我的代码，效果很好。这是源代码

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Windows.Input;
using Windows.Foundation;
using Windows.Foundation.Collections;
using System.Collections.ObjectModel;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Controls.Primitives;
using Windows.UI.Xaml.Data;
using Windows.UI.Xaml.Input;
using Windows.UI.Xaml.Media;
using Windows.UI.Xaml.Navigation;
using Windows.UI.Popups;
using System.Diagnostics;
using System.Collections.Specialized;


namespace App1
{


    public class HouseGuest
    {
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public string Role { get; set; }
        public bool Deleted { get; set; }
    }

    public class HouseGuestGroup : IGrouping<string, HouseGuest>
    {
        public ObservableCollection<HouseGuest> Items { get; set; }
        public string Role { get; set; }
        public HouseGuestGroup()
        {
            Items = new ObservableCollection<HouseGuest>();
        }

        public string Key
        {
            get { return Role; }
        }

        public IEnumerator<HouseGuest> GetEnumerator()
        {
            return Items.GetEnumerator();
        }

        System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()
        {
            return Items.GetEnumerator();
        }


    }

    public class BigBrotherModel : ObservableCollection<HouseGuestGroup>
    {
        public BigBrotherModel()
        {
            RemoveHouseGuestCommand = new DelegateCommand(RemoveHouseGuest);
        }

        public ICommand RemoveHouseGuestCommand { get; set; }

        void RemoveHouseGuest(object param)
        {
            Debug.Assert(param is HouseGuest);
            HouseGuest guest = param as HouseGuest;

            foreach (var g in Items)
            {
                if (g.Role == guest.Role)
                {
                    g.Items.Remove(guest);
                    break;
                }
            }
        }

    }

    public sealed partial class MainPage : Page
    {

        public MainPage()
        {
            this.InitializeComponent();

            HouseGuestGroup guestGroup;

            guestGroup = new HouseGuestGroup();
            guestGroup.Role = "Coach";
            guestGroup.Items.Add(new HouseGuest() { FirstName = "Britney", LastName = "Haynes", Role = "Coach" });
            guestGroup.Items.Add(new HouseGuest() { FirstName = "Dan", LastName = "Gheesling", Role = "Coach" });
            guestGroup.Items.Add(new HouseGuest() { FirstName = "Janelle", LastName = "Pierzina", Role = "Coach" });
            guestGroup.Items.Add(new HouseGuest() { FirstName = "Mike", LastName = "Boogie", Role = "Coach" });
            BBModel.Add(guestGroup);



            guestGroup = new HouseGuestGroup();
            guestGroup.Role = "Player";
            guestGroup.Items.Add(new HouseGuest() { FirstName = "Ian", LastName = "Terry", Role = "Player" });
            guestGroup.Items.Add(new HouseGuest() { FirstName = "Shane", LastName = "Meaney", Role = "Player" });
            guestGroup.Items.Add(new HouseGuest() { FirstName = "Wil", LastName = "Heuser", Role = "Player" });
            guestGroup.Items.Add(new HouseGuest() { FirstName = "Danielle", LastName = "Murphree", Role = "Player" });
            guestGroup.Items.Add(new HouseGuest() { FirstName = "Jenn", LastName = "Arroyo", Role = "Player" });
            guestGroup.Items.Add(new HouseGuest() { FirstName = "Jodi", LastName = "Rollins", Role = "Player" });
            guestGroup.Items.Add(new HouseGuest() { FirstName = "Ashley", LastName = "Iocco", Role = "Player" });
            BBModel.Add(guestGroup);

            groupInfo.Source = BBModel;
        }
    }
}

使用系统；
使用System.Collections.Generic；
使用System.IO；
使用System.Linq；
使用System.Windows.Input；
使用Windows基金会；
使用Windows。
使用System.Collections.ObjectModel；
使用Windows.UI.Xaml；
使用Windows.UI.Xaml.Controls；
使用Windows.UI.Xaml.Controls.Primitives；
使用Windows.UI.Xaml.Data；
使用Windows.UI.Xaml.Input；
使用Windows.UI.Xaml.Media；
使用Windows.UI.Xaml.Navigation；
使用Windows.UI.Popups；
使用系统诊断；
使用System.Collections.Specialized；
名称空间App1
{
公务舱房客
{
公共字符串名{get；set；}
公共字符串LastName{get；set；}
公共字符串角色{get；set；}
公共bool已删除{get；set；}
}
公共类客房组：iGroup
{
公共ObservableCollection项{get；set；}
公共字符串角色{get；set；}
公共住房宾客组（）
{
Items=新的ObservableCollection（）；
}
公共字符串密钥
{
void RemoveHouseGuest(object param)
{
    Debug.Assert(param is HouseGuest);
    if(houseGuests.Contains(param as HouseGuest))
        houseGuests.Remove(param);
    //(param as HouseGuest).Deleted = true;
    //RefreshListBox();
}