WPF MVVM:EventTrigger在CheckBox中不起作用 [英] WPF MVVM: EventTrigger is not working inside CheckBox

问题描述

我正在使用MVVM样式的WPF构建应用程序.当我选中或取消选中几个要过滤的复选框时，我正在尝试在DataGrid上进行过滤.

我已经找到了Interaction.Triggers的解决方案，但在这种情况下不适用于我.

这是我的代码:

<ListBox 
            ItemsSource="{Binding PortsFilterSource}"
            Background="LightGray"
            BorderThickness="0"
            Grid.Column="1">
            <ListBox.ItemTemplate>
                <DataTemplate>
                    <CheckBox 
                        Content="{Binding Name}"
                        IsChecked="{Binding IsChecked}">

                        <i:Interaction.Triggers>
                            <i:EventTrigger EventName="Unchecked">
                                <i:InvokeCommandAction Command="{Binding FilterCommand}"/>
                            </i:EventTrigger>
                            <i:EventTrigger EventName="Checked">
                                <i:InvokeCommandAction Command="{Binding FilterCommand}"/>
                            </i:EventTrigger>
                        </i:Interaction.Triggers>
                    </CheckBox>
                </DataTemplate>
            </ListBox.ItemTemplate>
        </ListBox>

除FilterCommand之外，其他所有工具都工作正常.我的C#代码中有这个代码:

public DelegateCommand<object> FilterCommand { get; set; }
...
FilterCommand = new DelegateCommand<object>(Filter);

Filter(object obj)是一项功能，但是当我选中或取消选中任何CheckBox时都不会输入.

任何帮助将不胜感激.

解决方案

问题是，列表项的数据上下文是FilterModel类型，但是FilterCommand在父视图模型中. >

尝试以下命令绑定:

{Binding DataContext.FilterCommand, RelativeSource={RelativeSource AncestorType={x:Type ListBox}}}

I'm building an application with WPF in MVVM style. I'm trying to make filter on my DataGrid when I check or uncheck several CheckBoxes for filtering.

I've found solution with Interaction.Triggers, but it's not working for me in this case.

Here is my code:

<ListBox 
            ItemsSource="{Binding PortsFilterSource}"
            Background="LightGray"
            BorderThickness="0"
            Grid.Column="1">
            <ListBox.ItemTemplate>
                <DataTemplate>
                    <CheckBox 
                        Content="{Binding Name}"
                        IsChecked="{Binding IsChecked}">

                        <i:Interaction.Triggers>
                            <i:EventTrigger EventName="Unchecked">
                                <i:InvokeCommandAction Command="{Binding FilterCommand}"/>
                            </i:EventTrigger>
                            <i:EventTrigger EventName="Checked">
                                <i:InvokeCommandAction Command="{Binding FilterCommand}"/>
                            </i:EventTrigger>
                        </i:Interaction.Triggers>
                    </CheckBox>
                </DataTemplate>
            </ListBox.ItemTemplate>
        </ListBox>

Everything is working great except FilterCommand. I have this in my C# code:

public DelegateCommand<object> FilterCommand { get; set; }
...
FilterCommand = new DelegateCommand<object>(Filter);

Filter(object obj) is a function, but it is not entered when I check or uncheck any of my CheckBoxes.

Any help would be very appreciated.

解决方案

The problem is, that the data context of the list item is of type FilterModel, but the FilterCommand is in the parent view model.

Try the following binding for the command:

{Binding DataContext.FilterCommand, RelativeSource={RelativeSource AncestorType={x:Type ListBox}}}

这篇关于WPF MVVM:EventTrigger在CheckBox中不起作用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！