3

我希望对某人来说是一个明显的问题。我希望在用户双击 ListBox 内的 ListBoxItem 时触发 Edit 命令。我以前在用户控件中做过这个，但想直接在一个视图中做，因为它是一个足够简单的列表框。但它不会接线。

这是列表框：

<ListBox SelectedItem="{Binding DataQuerySortSelected}"
         ItemContainerStyle="{StaticResource SortListItemStyle}"
         ItemsSource="{Binding DataQueryHolder.DataQuerySorts}">

    <ListBox.InputBindings>
        <KeyBinding Key="Delete" Command="{Binding DataQuerySortDelete}" />
    </ListBox.InputBindings>

    <ListBox.Resources>
        <Style TargetType="{x:Type ListBoxItem}">
            <Setter Property="AllowDrop" Value="True" />
            <EventSetter Event="PreviewMouseMove" Handler="DragDropListBoxItem_PreviewMouseMoveEvent" />
            <EventSetter Event="Drop" Handler="DragDropListBoxItem_Drop" />
        </Style>

    </ListBox.Resources>
</ListBox>

请注意，顶层的 Delete Key 绑定工作得很好。这是引用的样式（作为单独的 ResourceDictionary 引入，但将样式内联没有区别）：

<Style x:Key="SortListItemStyle" TargetType="ListBoxItem">
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="ListBoxItem">
                <Border Name="MainBorder">
                    <ContentPresenter>
                        <ContentPresenter.InputBindings>
                            <MouseBinding Gesture="LeftDoubleClick" Command="{Binding DataQuerySortEdit}" />
                        </ContentPresenter.InputBindings>
                    </ContentPresenter>

                    <Border.InputBindings>
                        <MouseBinding Gesture="LeftDoubleClick" Command="{Binding DataQuerySortEdit}" />
                    </Border.InputBindings>
                </Border>

                <ControlTemplate.Triggers>
                    <Trigger Property="IsSelected" Value="True">
                        <Setter TargetName="MainBorder" Value="Yellow" Property="Background" />
                    </Trigger>
                </ControlTemplate.Triggers>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

我将鼠标绑定放在两个地方只是为了看看它是否有所作为，但事实并非如此。那里没有任何接线。其他一切都按预期工作。如果我在视图中创建一个普通按钮并将其指向 DataQuerySortEdit 命令，它会按预期工作。

我错过了什么吗？谢谢你的帮助。

编辑：只需添加更多信息以响应 J 的回复。我为 ControlTemplate 的 Border 提供了一个相对于最近列表框的绑定，并为列表框命名，以便输出确认它会找到它。这是输出窗口：

System.Windows.Data Error: 40 : BindingExpression path error: 'DataQuerySortEdit' property not found on 'object' ''DataQuerySort' (HashCode=7641038)'. BindingExpression:Path=DataQuerySortEdit; DataItem='DataQuerySort' (HashCode=7641038); target element is 'MouseBinding' (HashCode=65119131); target property is 'Command' (type 'ICommand')
System.Windows.Data Error: 40 : BindingExpression path error: 'DataQuerySortEdit' property not found on 'object' ''DataQuerySort' (HashCode=50439840)'. BindingExpression:Path=DataQuerySortEdit; DataItem='DataQuerySort' (HashCode=50439840); target element is 'MouseBinding' (HashCode=3649016); target property is 'Command' (type 'ICommand')
System.Windows.Data Error: 40 : BindingExpression path error: 'DataQuerySortEdit' property not found on 'object' ''DataQuerySort' (HashCode=65588106)'. BindingExpression:Path=DataQuerySortEdit; DataItem='DataQuerySort' (HashCode=65588106); target element is 'MouseBinding' (HashCode=35717517); target property is 'Command' (type 'ICommand')
System.Windows.Data Error: 40 : BindingExpression path error: 'DataQuerySortEdit' property not found on 'object' ''DataQuerySort' (HashCode=32836053)'. BindingExpression:Path=DataQuerySortEdit; DataItem='DataQuerySort' (HashCode=32836053); target element is 'MouseBinding' (HashCode=66172851); target property is 'Command' (type 'ICommand')
System.Windows.Data Error: 40 : BindingExpression path error: 'DataQuerySortEdit' property not found on 'object' ''ListBox' (Name='SortListBox')'. BindingExpression:Path=DataQuerySortEdit; DataItem='ListBox' (Name='SortListBox'); target element is 'MouseBinding' (HashCode=28263486); target property is 'Command' (type 'ICommand')
System.Windows.Data Error: 40 : BindingExpression path error: 'DataQuerySortEdit' property not found on 'object' ''ListBox' (Name='SortListBox')'. BindingExpression:Path=DataQuerySortEdit; DataItem='ListBox' (Name='SortListBox'); target element is 'MouseBinding' (HashCode=27134857); target property is 'Command' (type 'ICommand')
System.Windows.Data Error: 40 : BindingExpression path error: 'DataQuerySortEdit' property not found on 'object' ''ListBox' (Name='SortListBox')'. BindingExpression:Path=DataQuerySortEdit; DataItem='ListBox' (Name='SortListBox'); target element is 'MouseBinding' (HashCode=7437765); target property is 'Command' (type 'ICommand')
System.Windows.Data Error: 40 : BindingExpression path error: 'DataQuerySortEdit' property not found on 'object' ''ListBox' (Name='SortListBox')'. BindingExpression:Path=DataQuerySortEdit; DataItem='ListBox' (Name='SortListBox'); target element is 'MouseBinding' (HashCode=58400697); target property is 'Command' (type 'ICommand')

因此，第二次尝试绑定（我猜是 Border InputBinding 中的那个）确实可以很好地找到正确的列表框，但仍然找不到 ICommand。我尝试对窗口、包含列表的网格等进行相对查找，但仍然无法连接。正如 J 提到的那样，我还尝试将相对搜索直接放在 MouseBindings 中，它们会导致相同的错误。

EDIT2：这里是 ViewModel 中的命令和属性，使用 MVVMLight

public DataQuerySort DataQuerySortSelected
{
    get { return _DataQuerySortSelected; }
    set { NotifySetProperty(ref _DataQuerySortSelected, value, () => DataQuerySortSelected); }
}
private DataQuerySort _DataQuerySortSelected;


public RelayCommand DataQuerySortEdit
{
    get { return new RelayCommand(_DataQuerySortEdit, CanDataQuerySortEdit); }
}
private void _DataQuerySortEdit()
{
    DataQuerySortHolder = DataQuerySortSelected.Copy();
    DataQuerySortEditMode = EditMode.Edit;
}    
private bool CanDataQuerySortEdit() 
{ 
    return DataQuerySortSelected != null; 
}

取出 CanDataQuerySortEdit 没有区别。我知道一切正常，因为如果我创建一个按钮并指向它，它就可以工作。如果我还在 ListBox 中为鼠标创建一个输入绑定，例如有效的 Delete 键 - 当然，只要我在 ListBoxItems 之外单击即可。

EDIT3：这是视图本身的一部分，包括类、数据上下文和资源。我尝试将相对绑定设置为“{x:Type Window}”和“{x:Type l:ToolkitWindowBase}”。ToolkitWindowBase 直接扩展了 Window。frmDataBrowserViewModel 扩展了一个名为 ToolkitViewModelBase 的类，它从 MVVMLight 扩展了 ViewModelBase：

<l:ToolkitWindowBase x:Class="GISToolkit.frmDataBrowser"  x:Name="mainWindow" Icon="Images/favicon.ico" 
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008" mc:Ignorable="d"
    xmlns:l="clr-namespace:GISToolkit;assembly="
    xmlns:lc="clr-namespace:GISToolkit.Controls;assembly="
    xmlns:ls="clr-namespace:GISToolkit.Settings;assembly="
    xmlns:system="clr-namespace:System;assembly=mscorlib"
    xmlns:xctk="clr-namespace:Xceed.Wpf.Toolkit;assembly=Xceed.Wpf.Toolkit"
    xmlns:xctkp="clr-namespace:Xceed.Wpf.Toolkit.Primitives;assembly=Xceed.Wpf.Toolkit"
    Title="Solutions GIS Toolkit - Setup"  
    ResizeMode="CanResizeWithGrip" Foreground="White"
    l:ControlBox.HasMaximizeButton="False" l:ControlBox.HasMinimizeButton="False" l:ControlBox.HasCloseButton="False"
    Height="{Binding RunTimeHeight, Mode=TwoWay}" 
    Width="{Binding RunTimeWidth, Mode=TwoWay}" IsSettingsDirty="{Binding IsCurrentSettingsDirty}" IsEnabled="True">

    <Window.DataContext>
        <l:frmDataBrowserViewModel />
    </Window.DataContext>

    <Window.Resources>
        <ResourceDictionary>
            <ResourceDictionary.MergedDictionaries>
                <ResourceDictionary Source="Themes/DataBrowser.xaml"/>
            </ResourceDictionary.MergedDictionaries>
        </ResourceDictionary>
    </Window.Resources>

    ..................
<l:ToolkitWindowBase />

EDIT4：以防万一有人还在列出，帮我一个忙，创建一个名为“WpfMvvmApplication1”的新WPF项目，其中有一个名为“BindingTestWindow”的窗口和一个名为“MainWindowViewModel”的视图模型然后放置窗口（应该很简单剪切/粘贴，除非您为文件/项目使用不同的名称）：

<Window x:Class="WpfMvvmApplication1.BindingTestWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:l="clr-namespace:WpfMvvmApplication1"
        Title="BindingTestWindow" Height="300" Width="300">

    <Window.DataContext>
        <l:BindingTestViewModel />
    </Window.DataContext>

    <Grid>
        <GroupBox Header="Sorting:" >
            <Grid>
                <ListBox Background="White" Name="SortListBox" ItemsSource="{Binding TestCollection}">

                    <ListBox.InputBindings>
                        <KeyBinding Key="Delete" Command="{Binding TestCommand}" />
                    </ListBox.InputBindings>

                    <ListBox.Resources>
                        <Style TargetType="{x:Type ListBoxItem}">
                            <Setter Property="AllowDrop" Value="True" />
                            <Setter Property="Template">
                                <Setter.Value>
                                    <ControlTemplate TargetType="ListBoxItem">
                                        <Border Name="MainBorder" Padding="0" Margin="0">
                                            <ContentPresenter />

                                            <Border.InputBindings>
                                                <MouseBinding Gesture="LeftDoubleClick" Command="{Binding TestCommand, RelativeSource={RelativeSource AncestorType={x:Type Window}}}" />
                                            </Border.InputBindings>
                                        </Border>

                                        <ControlTemplate.Triggers>
                                            <Trigger Property="IsSelected" Value="True">
                                                <Setter TargetName="MainBorder" Value="Yellow" Property="Background" />
                                            </Trigger>
                                        </ControlTemplate.Triggers>
                                    </ControlTemplate>
                                </Setter.Value>
                            </Setter>
                        </Style>
                    </ListBox.Resources>
                </ListBox>
            </Grid>
        </GroupBox>
    </Grid>
</Window>

对于 VIEWMODEL：

using System;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Linq.Expressions;
using System.Windows.Input;

namespace WpfMvvmApplication1
{
    public class BindingTestViewModel : NotificationObject
    {
        public BindingTestViewModel()
        {
            TestCollection = new ObservableCollection<string>();
            for (int i = 0; i < 10; i++ )
                TestCollection.Add("test" + i);
        }

        public ICommand TestCommand { get { return new DelegateCommand(_TestCommand); } }

        private void _TestCommand() { System.Diagnostics.Debugger.Break(); }

        public ObservableCollection<string> TestCollection
        {
            get { return _TestCollection; }
            set 
            {
                _TestCollection = value;
                RaisePropertyChanged(() => TestCollection);
            }
        }
        private ObservableCollection<string> _TestCollection;
    }

    public class DelegateCommand : ICommand
    {
        private readonly Action _command;
        private readonly Func<bool> _canExecute;
        public event EventHandler CanExecuteChanged
        {
            add { CommandManager.RequerySuggested += value; }
            remove { CommandManager.RequerySuggested -= value; }
        }

        public DelegateCommand(Action command, Func<bool> canExecute = null)
        {
            if (command == null)
                throw new ArgumentNullException();
            _canExecute = canExecute;
            _command = command;
        }

        public void Execute(object parameter)
        {
            _command();
        }

        public bool CanExecute(object parameter)
        {
            return _canExecute == null || _canExecute();
        }

    }

    public class NotificationObject : INotifyPropertyChanged
    {
        protected void RaisePropertyChanged<T>(Expression<Func<T>> action)
        {
            var propertyName = GetPropertyName(action);
            RaisePropertyChanged(propertyName);
        }

        private static string GetPropertyName<T>(Expression<Func<T>> action)
        {
            var expression = (MemberExpression)action.Body;
            var propertyName = expression.Member.Name;
            return propertyName;
        }

        private void RaisePropertyChanged(string propertyName)
        {
            if (PropertyChanged != null)
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
        }

        public event PropertyChangedEventHandler PropertyChanged;
    }
}

这里面没有别的东西。当输入绑定在 listboxtiem 内时，它给了我绑定错误，但在列表框本身时却没有。似乎它应该可以工作，因为输出表明它确实在 FindAncestor 中找到了窗口。

4

3 回答 3

1

尝试将您的命令绑定更改为以下代码。列表框项是列表框的可视子项，您需要正确连接数据上下文。我认为。注意窗口类型。将其更改为您的顶级数据上下文是声明命令且存在列表框的位置。即：用户控件、窗口等...

<MouseBinding Gesture="LeftDoubleClick" Command="{Binding DataQuerySortEdit, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}}}}" />

当您运行您的应用程序时，您可以通过查看输出窗口来调试它，它会向您显示这样的绑定错误。

编辑 1：Mvvm 灯光事件命令

好吧，我完全忽略了你起诉 Mvvm Light 的事实。MVVM-Light 有一个内置函数，用于将事件绑定到视图模型上的命令。

将以下内容添加到您的 Windows 命名空间中：

xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
xmlns:cmd="http://www.galasoft.ch/mvvmlight"

现在更改列表框项内的边框以包含以下内容：

<Border ...>
    <i:Interaction.Triggers>
        <i:EventTrigger EventName="LeftDoubleClick">
            <cmd:EventToCommand Command="{Binding DataContext.DataQuerySortEdit, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}}}"/>
        </i:EventTrigger>
    </i:Interaction.Triggers>
</Border>

Mvvm light 已经建立了这个，以便准确地促进您正在寻找的东西。它允许您接受任何事件并将命令绑​​定到它。我通过控件的 lostfocus 事件等使用它进行表单验证。

确保您的项目中有以下引用：

  • GalaSoft.MvvmLight.WPF45
  • GalaSoft.MvvmLight.Extras.WPF45
  • Microsoft.Expression.Interactions

希望这可以帮助

编辑 3：

只是最后的努力，如果您使用以下内容：

它将 Datacontext 添加到命令名称中。

于 2013-11-14T18:01:32.787 回答
0

非常感谢 J King 的参与。但似乎在 XAML 中做是行不通的。我最终在 VIEW 后面的代码中执行了此操作（希望它可以帮助某人）：

public BindingTestWindow()
{
    InitializeComponent();

    SortListBox.ItemContainerGenerator.StatusChanged += ItemContainerGenerator_StatusChanged;
}

private void ItemContainerGenerator_StatusChanged(object sender, EventArgs e)
{
    if (SortListBox.ItemContainerGenerator.Status == System.Windows.Controls.Primitives.GeneratorStatus.ContainersGenerated)
    {
        BindingTestViewModel vm = (BindingTestViewModel)this.DataContext;

        for(int i = 0; i < SortListBox.Items.Count; i++)
        {
            ListBoxItem lbi = (ListBoxItem)SortListBox.ItemContainerGenerator.ContainerFromIndex(i);
            lbi.InputBindings.Clear();
            lbi.InputBindings.Add(new InputBinding(vm.TestCommand, new MouseGesture(MouseAction.LeftDoubleClick)));
        }
    }
}

为了操作实际的列表框项（而不是通过 ListBox.Items 处理它们的内容），我们必须使用 ItemContainerGenerator。但为了做到这一点，您必须等待它完全生成，因此需要事件处理程序。它不漂亮，但它有效。

厄尼

于 2013-11-17T13:41:35.180 回答
0

我花了相当多的时间摆弄这个问题。设法将一些答案与有效的结果混合在一起。ListBox 上的输入绑定有一个奇怪的行为。ListBox 本身的一些工作，如 MiddleClick，其他需要在项目上实现。J Kings 绑定到 DataContext 在 LisBoxItemStyle 的 ContentPresenter 中发挥了作用。

 <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type ListBoxItem}">

                    <Border x:Name="Bd" 
                            BorderBrush="{TemplateBinding BorderBrush}" 
                            BorderThickness="{TemplateBinding BorderThickness}" 
                            Background="{TemplateBinding Background}" 
                            Padding="{TemplateBinding Padding}" 
                            SnapsToDevicePixels="true">

                        <ContentPresenter HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" 
                                          SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" 
                                          VerticalAlignment="{TemplateBinding VerticalContentAlignment}">
                            <ContentPresenter.InputBindings>
                                <MouseBinding Gesture="Ctrl+MiddleClick" 
                                              Command="{Binding  DataContext.MiddleClickCommand, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}}}"/>
                                <MouseBinding Gesture="Ctrl+RightClick" 
                                              Command="{Binding DataContext.CtrlRightClickCommand, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}}}"/>
                                <MouseBinding MouseAction="RightClick" 
                                              Command="{Binding DataContext.RightClickCommand, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}}}"/>
                            </ContentPresenter.InputBindings>
                        </ContentPresenter>
                    </Border>
                    <ControlTemplate.Triggers>
                        <MultiTrigger>
                            <MultiTrigger.Conditions>
                                <Condition Property="IsMouseOver" Value="True"/>
                            </MultiTrigger.Conditions>
                            <Setter Property="Background" TargetName="Bd" Value="{StaticResource Item.MouseOver.Background}"/>
                            <Setter Property="BorderBrush" TargetName="Bd" Value="{StaticResource Item.MouseOver.Border}"/>
                        </MultiTrigger>
                        <MultiTrigger>
                            <MultiTrigger.Conditions>
                                <Condition Property="Selector.IsSelectionActive" Value="False"/>
                                <Condition Property="IsSelected" Value="True"/>
                            </MultiTrigger.Conditions>
                            <Setter Property="Background" TargetName="Bd" Value="{StaticResource Item.SelectedInactive.Background}"/>
                            <Setter Property="BorderBrush" TargetName="Bd" Value="{StaticResource Item.SelectedInactive.Border}"/>
                        </MultiTrigger>
                        <MultiTrigger>
                            <MultiTrigger.Conditions>
                                <Condition Property="Selector.IsSelectionActive" Value="True"/>
                                <Condition Property="IsSelected" Value="True"/>
                            </MultiTrigger.Conditions>
                            <Setter Property="Background" TargetName="Bd" Value="{StaticResource Item.SelectedActive.Background}"/>
                            <Setter Property="BorderBrush" TargetName="Bd" Value="{StaticResource Item.SelectedActive.Border}"/>
                        </MultiTrigger>
                        <Trigger Property="IsEnabled" Value="False">
                            <Setter Property="TextElement.Foreground" TargetName="Bd" Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}"/>
                        </Trigger>
                    </ControlTemplate.Triggers>

                </ControlTemplate>
            </Setter.Value>
        </Setter>
于 2018-09-23T11:32:02.047 回答