2

我有 TextBox 驻留在样式资源字典中的 DataGridColumnHeader 中，TextBox 用作过滤器，所以我需要触发 TextChanged 事件并在 View Model 中处理它以实现过滤过程。重点是我需要遵守以下规则：

  1. 没有代码背后
  2. 视图模型中的事件处理
  3. 使用样式能够一致地将其应用于所有 DataGrid
  4. 将事件参数传递给视图模型以在过滤过程中使用

我做了很多谷歌搜索，但找不到符合所有这些规则的解决方案。提前致谢

编辑：这是定义文本框的资源字典的完整 xaml。注意：我正在使用 MVVM Light EventToCommand 尝试将文本框的 TextChanged 事件绑定到视图模型中的附加行为 另请注意，这个 xamle 仍在开发和修改中，知道我从 DataGrid 过滤应用程序中获得了大部分内容

enter code here
    <ResourceDictionary x:Class="PreCommissioning.Infrastructure.Filter2.FilteringDataGrid"
 xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
 xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
 xmlns:dg="http://schemas.microsoft.com/wpf/2008/toolkit"
 xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"      
 xmlns:cmd="clr-namespace:GalaSoft.MvvmLight.Command;assembly=GalaSoft.MvvmLight.Extras.WPF4"                   
 xmlns:local="clr-namespace:PreCommissioning.Infrastructure.Filter2;assembly=PreCommissioning.Infrastructure"
 xmlns:localx="clr-namespace:PreCommissioning.Module.Subsystem.ViewModel;assembly=PreCommissioning.Module.Subsystem"    
 xmlns:my="http://schemas.microsoft.com/wpf/2008/toolkit"
>

    <local:HeaderFilterConverter x:Key="headerConverter"/>

        <Style TargetType="{x:Type DataGridColumnHeader}">
            <Setter Property="VerticalContentAlignment" Value="Center"/>
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="{x:Type DataGridColumnHeader}">
                        <ControlTemplate.Resources>
                            <Storyboard x:Key="ShowFilterControl">
                                <ObjectAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetName="filterTextBox" Storyboard.TargetProperty="(UIElement.Visibility)">
                                    <DiscreteObjectKeyFrame KeyTime="00:00:00" Value="{x:Static Visibility.Visible}"/>
                                    <DiscreteObjectKeyFrame KeyTime="00:00:00.5000000" Value="{x:Static Visibility.Visible}"/>
                                </ObjectAnimationUsingKeyFrames>
                                <ColorAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetName="filterTextBox" Storyboard.TargetProperty="(Panel.Background).(SolidColorBrush.Color)">
                                    <SplineColorKeyFrame KeyTime="00:00:00" Value="Transparent"/>
                                    <SplineColorKeyFrame KeyTime="00:00:00.5000000" Value="White"/>
                                </ColorAnimationUsingKeyFrames>
                            </Storyboard>
                            <Storyboard x:Key="HideFilterControl">
                                <ObjectAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetName="filterTextBox" Storyboard.TargetProperty="(UIElement.Visibility)">
                                    <DiscreteObjectKeyFrame KeyTime="00:00:00.4000000" Value="{x:Static Visibility.Collapsed}"/>
                                </ObjectAnimationUsingKeyFrames>
                                <ColorAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetName="filterTextBox" Storyboard.TargetProperty="(UIElement.OpacityMask).(SolidColorBrush.Color)">
                                    <SplineColorKeyFrame KeyTime="00:00:00" Value="Black"/>
                                    <SplineColorKeyFrame KeyTime="00:00:00.4000000" Value="#00000000"/>
                                </ColorAnimationUsingKeyFrames>
                            </Storyboard>
                        </ControlTemplate.Resources>
                        <my:DataGridHeaderBorder x:Name="dataGridHeaderBorder" Margin="0" VerticalAlignment="Top" Height="31" IsClickable="{TemplateBinding CanUserSort}" IsHovered="{TemplateBinding IsMouseOver}" IsPressed="{TemplateBinding IsPressed}" SeparatorBrush="{TemplateBinding SeparatorBrush}" SeparatorVisibility="{TemplateBinding SeparatorVisibility}" SortDirection="{TemplateBinding SortDirection}" Background="{TemplateBinding Background}" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Padding="{TemplateBinding Padding}" Grid.ColumnSpan="1">
                            <Grid x:Name="grid" Width="Auto" Height="Auto" RenderTransformOrigin="0.5,0.5">
                                <Grid.RenderTransform>
                                    <TransformGroup>
                                        <ScaleTransform/>
                                        <SkewTransform/>
                                        <RotateTransform/>
                                        <TranslateTransform/>
                                    </TransformGroup>
                                </Grid.RenderTransform>
                                <Grid.ColumnDefinitions>
                                    <ColumnDefinition Width="*"/>
                                </Grid.ColumnDefinitions>
                                <ContentPresenter x:Name="contentPresenter"
                                    HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" 
                                    VerticalAlignment="{TemplateBinding VerticalContentAlignment}" 
                                    SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" 
                                    ContentStringFormat="{TemplateBinding ContentStringFormat}" 
                                    ContentTemplate="{TemplateBinding ContentTemplate}">
                                    <ContentPresenter.Content>
                                        <MultiBinding Converter="{StaticResource headerConverter}">
                                            <MultiBinding.Bindings>
                                                <Binding ElementName="filterTextBox" Path="Text" />
                                                <Binding RelativeSource="{RelativeSource TemplatedParent}" Path="Content" />
                                            </MultiBinding.Bindings>
                                        </MultiBinding>
                                    </ContentPresenter.Content>
                                </ContentPresenter>

                            <!--Filter Text Box-->    
                            <TextBox x:Name="filterTextBox" HorizontalAlignment="Right" 
                                         MinWidth="25" Height="Auto" OpacityMask="Black" Visibility="Collapsed" 
                                         Text="" 
                                         TextWrapping="Wrap" Grid.Column="0" Grid.ColumnSpan="1">
                                <i:Interaction.Triggers>
                                    <i:EventTrigger EventName="TextChanged">
                                        <cmd:EventToCommand  Command="{Binding Path=DataContext.TextChangedCommand, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type UserControl}}}"
                                                             PassEventArgsToCommand="True"
                                                             CommandParameter="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type TextBox}}, Path=Name}"/>
                                    </i:EventTrigger>
                                </i:Interaction.Triggers>
                            </TextBox>

                        </Grid>
                        </my:DataGridHeaderBorder>
                        <ControlTemplate.Triggers>
                            <Trigger Property="IsMouseOver" Value="True">
                                <Trigger.EnterActions>
                                    <BeginStoryboard x:Name="ShowFilterControl_BeginStoryboard" Storyboard="{StaticResource ShowFilterControl}"/>
                                    <StopStoryboard BeginStoryboardName="HideFilterControl_BeginShowFilterControl"/>
                                </Trigger.EnterActions>
                                <Trigger.ExitActions>
                                    <BeginStoryboard x:Name="HideFilterControl_BeginShowFilterControl" Storyboard="{StaticResource HideFilterControl}"/>
                                    <StopStoryboard BeginStoryboardName="ShowFilterControl_BeginStoryboard"/>
                                </Trigger.ExitActions>
                            </Trigger>
                        </ControlTemplate.Triggers>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>


    <Style x:Key="DataGridStyle" TargetType="DataGrid">
        <Setter Property="ScrollViewer.CanContentScroll" Value="true"/>
        <Setter Property="SnapsToDevicePixels" Value="True" />
        <Setter Property="AlternatingRowBackground" Value="#00FFFFFF"/>
        <Setter Property="VerticalGridLinesBrush" Value="#FFC9CACA"/>
        <Setter Property="HorizontalGridLinesBrush" Value="#FFC9CACA"/>
        <Setter Property="AutoGenerateColumns" Value="False"/>
        <!--

        -->
        <Style.Triggers>
            <Trigger Property="IsGrouping" Value="true">
                <Setter Property="ScrollViewer.CanContentScroll" Value="false"/>
            </Trigger>
        </Style.Triggers>
    </Style>


</ResourceDictionary>
4

1 回答 1

0

我在我的应用程序中实现了一个非常相似的过滤器文本。它与命令一起使用，将参数作为当前文本。我希望这就是你要找的东西（看到这个问题这些年来仍然没有答案有点晚了）

<StackPanel Grid.Row="0" Orientation="Horizontal">
        <Label Content="Filter names by " ></Label>
        <TextBox Name="txtFilter" Width="290" Height="25" VerticalAlignment="Center" Text="{Binding FilterText, UpdateSourceTrigger=PropertyChanged}"
                 BorderBrush="DarkGray" BorderThickness="0,0,0,1">
            <i:Interaction.Triggers>
                <i:EventTrigger EventName="TextChanged">
                    <i:InvokeCommandAction Command="{Binding FilterItemsCommand}"></i:InvokeCommandAction>
                </i:EventTrigger>
            </i:Interaction.Triggers>
        </TextBox>
    </StackPanel>

在各自的 ViewModel 中，我有以下代码行来使用过滤器操作。

ViewModel 构造函数：

FilterItemsCommand = new RelayCommand(_ => FilterItems(), _ => CanFilterItems);
FilterText = string.Empty;

和过滤器命令逻辑：

    [NotifyPropertyChanged]
    public string FilterText { get; set; }
    public ICommand FilterItemsCommand
    {
        get;
        set;
    }

    public void FilterItems()
    {
        // to load the items from source so every filter change will be from the source. 
        if (string.IsNullOrWhiteSpace(FilterText))
            PopulateItems(); //imagine i am loading a set of items from source to display in the UI
        else PopulateItems(filter: FilterText);
    }

    public bool CanFilterItems
    {
        get
        {
            return (Items != null);
        }
    }

如果您对 PopulateItems 方法感兴趣，

private void PopulateLaunchItems(string filter = "")
    {
        // Add items
        Items = new ObservableCollection<SomeItemType>();

        // use your filter to manipulate the data from source
        ...
        ...
    }

这是一段工作代码。我希望这对将来的某人有所帮助，即使最初被问到的人可能已经继续前进。;-)

于 2020-01-06T22:15:23.793 回答