根据值更改 DataGrid 单元格颜色

Question

我有一个 WPF 数据网格，我想要根据值使用不同的单元格颜色。我的 xaml 上有以下代码

Style TargetType="DataGridCell"

但不是只选择一个单元格而是选择所有行？我错过了什么？

Answer 1

 <DataGridTextColumn  Binding="{Binding Name}" Header="Name" Foreground="White">
     <DataGridTextColumn.CellStyle>
      <Style TargetType="{x:Type DataGridCell}">
         <Setter Property="Background" Value="{Binding color}" />
      </Style>
     </DataGridTextColumn.CellStyle>
 </DataGridTextColumn>

在 xaml.cs 文件中

SolidColorBrush color=new SolidColorBrush(Colors.Red);

Answer 2

如果您尝试设置DataGrid.CellStyle，DataContext 将是行，因此如果您想根据一个单元格更改颜色，那么在特定列中这样做可能是最简单的，特别是因为列可以有不同的内容，像文本块、组合框和复选框。这是将Name 为John 的所有单元格设置为浅绿色的示例：

<DataGridTextColumn Binding="{Binding Name}">
    <DataGridTextColumn.ElementStyle>
        <Style TargetType="{x:Type TextBlock}">
            <Style.Triggers>
                <Trigger Property="Text" Value="John">
                    <Setter Property="Background" Value="LightGreen"/>
                </Trigger>
            </Style.Triggers>
        </Style>
    </DataGridTextColumn.ElementStyle>
</DataGridTextColumn>

---

您也可以使用ValueConverter 来更改颜色。

public class NameToBrushConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        string input = (string)value;
        switch (input)
        {
            case "John":
                return Brushes.LightGreen;
            default:
                return DependencyProperty.UnsetValue;
        }
    }

    public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        throw new NotSupportedException();
    }
}

用法：

<Window.Resources>
    <local:NameToBrushConverter x:Key="NameToBrushConverter"/>
</Window.Resources>
...
<DataGridTextColumn Binding="{Binding Name}">
    <DataGridTextColumn.ElementStyle>
        <Style TargetType="{x:Type TextBlock}">
            <Setter Property="Background" Value="{Binding Name, Converter={StaticResource NameToBrushConverter}}"/>
        </Style>
    </DataGridTextColumn.ElementStyle>
</DataGridTextColumn>

---

另一种选择是将Background 直接绑定到返回相应颜色画笔的属性。您必须在颜色所依赖的属性的设置器中触发属性更改通知。

例如

public string Name
{
    get { return _name; }
    set
    {
        if (_name != value)
        {
            _name = value;
            OnPropertyChanged(nameof(Name));
            OnPropertyChanged(nameof(NameBrush));
        }
    }
}

public Brush NameBrush
{
    get
    {
        switch (Name)
        {
            case "John":
                return Brushes.LightGreen;
            default:
                break;
        }

        return Brushes.Transparent;
    }
}

Answer 3

基于“Cassio Borghi”的回答。使用这种方法，根本不需要更改 XAML。

        DataGridTextColumn colNameStatus2 = new DataGridTextColumn();
        colNameStatus2.Header = "Status";
        colNameStatus2.MinWidth = 100;
        colNameStatus2.Binding = new Binding("Status");
        grdComputer_Servives.Columns.Add(colNameStatus2);

        Style style = new Style(typeof(TextBlock));
        Trigger running = new Trigger() { Property = TextBlock.TextProperty, Value = "Running" };
        Trigger stopped = new Trigger() { Property = TextBlock.TextProperty, Value = "Stopped" };

        stopped.Setters.Add(new Setter() { Property = TextBlock.BackgroundProperty, Value = Brushes.Blue });
        running.Setters.Add(new Setter() { Property = TextBlock.BackgroundProperty, Value = Brushes.Green });

        style.Triggers.Add(running);
        style.Triggers.Add(stopped);

        colNameStatus2.ElementStyle = style;

        foreach (var Service in computerResult)
        {
            var RowName = Service;  
            grdComputer_Servives.Items.Add(RowName);
        }

Answer 4

这可能对您有所帮助。然而，它不是普通的 WPF 数据网格。

我使用带有自定义 ColorFormatter 行为的 DevExpress。我在市场上找不到任何开箱即用的产品。这花了我几天的时间来开发。我的代码附在下面，希望这对那里的人有所帮助。

编辑：我使用了 POCO 视图模型和 MVVM，但是您可以根据需要将其更改为不使用 POCO。

Viewmodel.cs

namespace ViewModel
{
    [POCOViewModel]
    public class Table2DViewModel
    {
        public ITable2DView Table2DView { get; set; }

        public DataTable ItemsTable { get; set; }


        public Table2DViewModel()
        {
        }

        public Table2DViewModel(MainViewModel mainViewModel, ITable2DView table2DView) : base(mainViewModel)
        {
            Table2DView = table2DView;   
            CreateTable();
        }

        private void CreateTable()
        {
            var dt = new DataTable();
            var xAxisStrings = new string[]{"X1","X2","X3"};
            var yAxisStrings = new string[]{"Y1","Y2","Y3"};

            //TODO determine your min, max number for your colours
            var minValue = 0;
            var maxValue = 100;
            Table2DView.SetColorFormatter(minValue,maxValue, null);

            //Add the columns
            dt.Columns.Add(" ", typeof(string));
            foreach (var x in xAxisStrings) dt.Columns.Add(x, typeof(double));

            //Add all the values
            double z = 0;
            for (var y = 0; y < yAxisStrings.Length; y++)
            {
                var dr = dt.NewRow();
                dr[" "] = yAxisStrings[y];
                for (var x = 0; x < xAxisStrings.Length; x++)
                {
                    //TODO put your actual values here!
                    dr[xAxisStrings[x]] = z++; //Add a random values
                }
                dt.Rows.Add(dr);
            }
            ItemsTable = dt;
        }


        public static Table2DViewModel Create(MainViewModel mainViewModel, ITable2DView table2DView)
        {
            var factory = ViewModelSource.Factory((MainViewModel mainVm, ITable2DView view) => new Table2DViewModel(mainVm, view));
            return factory(mainViewModel, table2DView);
        }
    }

}

IView.cs

namespace Interfaces
    {
        public interface ITable2DView
        {
            void SetColorFormatter(float minValue, float maxValue, ColorScaleFormat colorScaleFormat);
        }
    }

View.xaml.cs

namespace View
{
    public partial class Table2DView : ITable2DView
    {
        public Table2DView()
        {
            InitializeComponent();
        }

        static ColorScaleFormat defaultColorScaleFormat = new ColorScaleFormat
        {
            ColorMin = (Color)ColorConverter.ConvertFromString("#FFF8696B"),
            ColorMiddle = (Color)ColorConverter.ConvertFromString("#FFFFEB84"),
            ColorMax = (Color)ColorConverter.ConvertFromString("#FF63BE7B")
        };

        public void SetColorFormatter(float minValue, float maxValue, ColorScaleFormat colorScaleFormat = null)
        {
            if (colorScaleFormat == null) colorScaleFormat = defaultColorScaleFormat;
            ConditionBehavior.MinValue = minValue;
            ConditionBehavior.MaxValue = maxValue;
            ConditionBehavior.ColorScaleFormat = colorScaleFormat;
        }
    }
}

DynamicConditionBehavior.cs

namespace Behaviors
{
    public class DynamicConditionBehavior : Behavior<GridControl>
    {
        GridControl Grid => AssociatedObject;

        protected override void OnAttached()
        {
            base.OnAttached();
            Grid.ItemsSourceChanged += OnItemsSourceChanged;
        }

        protected override void OnDetaching()
        {
            Grid.ItemsSourceChanged -= OnItemsSourceChanged;
            base.OnDetaching();
        }

        public ColorScaleFormat ColorScaleFormat { get; set;}
        public float MinValue { get; set; }
        public float MaxValue { get; set; }

        private void OnItemsSourceChanged(object sender, EventArgs e)
        {
            var view = Grid.View as TableView;

            if (view == null) return;

            view.FormatConditions.Clear();

            foreach (var col in Grid.Columns)
            {
                view.FormatConditions.Add(new ColorScaleFormatCondition
                {
                    MinValue = MinValue,
                    MaxValue = MaxValue,
                    FieldName = col.FieldName,
                    Format = ColorScaleFormat,
                });
            }

        }
    }
}

View.xaml

<UserControl x:Class="View"
             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"
             xmlns:dxmvvm="http://schemas.devexpress.com/winfx/2008/xaml/mvvm" 
             xmlns:ViewModels="clr-namespace:ViewModel"
             xmlns:dxg="http://schemas.devexpress.com/winfx/2008/xaml/grid"
             xmlns:behaviors="clr-namespace:Behaviors"
             xmlns:dxdo="http://schemas.devexpress.com/winfx/2008/xaml/docking"
             DataContext="{dxmvvm:ViewModelSource Type={x:Type ViewModels:ViewModel}}"
             mc:Ignorable="d" d:DesignHeight="300" d:DesignWidth="800">

    <UserControl.Resources>
        <Style TargetType="{x:Type dxg:GridColumn}">
            <Setter Property="Width" Value="50"/>
            <Setter Property="HorizontalHeaderContentAlignment" Value="Center"/>
        </Style>

        <Style TargetType="{x:Type dxg:HeaderItemsControl}">
            <Setter Property="FontWeight" Value="DemiBold"/>
        </Style>
    </UserControl.Resources>

        <!--<dxmvvm:Interaction.Behaviors>
            <dxmvvm:EventToCommand EventName="" Command="{Binding OnLoadedCommand}"/>
        </dxmvvm:Interaction.Behaviors>-->
        <dxg:GridControl ItemsSource="{Binding ItemsTable}"
                     AutoGenerateColumns="AddNew"
                     EnableSmartColumnsGeneration="True">

        <dxmvvm:Interaction.Behaviors >
            <behaviors:DynamicConditionBehavior x:Name="ConditionBehavior" />
            </dxmvvm:Interaction.Behaviors>
            <dxg:GridControl.View>
                <dxg:TableView ShowGroupPanel="False"
                           AllowPerPixelScrolling="True"/>
            </dxg:GridControl.View>
        </dxg:GridControl>
  </UserControl>

Answer 5

在我的情况下转换器必须返回字符串值。我不知道为什么，但它有效。

*.xaml（通用样式文件，包含在另一个xaml文件中）

<Style TargetType="DataGridCell">
        <Setter Property="Background" Value="{Binding RelativeSource={RelativeSource Self}, Converter={StaticResource ValueToBrushConverter}}" />
</Style>

*.cs

public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
    Color color = VSColorTheme.GetThemedColor(EnvironmentColors.ToolWindowBackgroundColorKey);
    return "#" + color.Name;
}

Answer 6

如果您需要使用一定数量的列来执行此操作，那么 H.B. 的方式是最好的。但是，如果您在运行时之前不知道要处理多少列，那么下面的代码 [re​​ad: hack] 将起作用。我不确定是否有更好的解决方案，列数未知。我断断续续地花了两天时间才得到它，所以无论如何我都会坚持下去。

C#

public class ValueToBrushConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        int input;
        try
        {
            DataGridCell dgc = (DataGridCell)value;
            System.Data.DataRowView rowView = (System.Data.DataRowView)dgc.DataContext;
            input = (int)rowView.Row.ItemArray[dgc.Column.DisplayIndex];
        }
        catch (InvalidCastException e)
        {
            return DependencyProperty.UnsetValue;
        }
        switch (input)
        {
            case 1: return Brushes.Red;
            case 2: return Brushes.White;
            case 3: return Brushes.Blue;
            default: return DependencyProperty.UnsetValue;
        }
    }

    public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        throw new NotSupportedException();
    }
}

XAML

<UserControl.Resources>
    <conv:ValueToBrushConverter x:Key="ValueToBrushConverter"/>
    <Style x:Key="CellStyle" TargetType="DataGridCell">
        <Setter Property="Background" Value="{Binding RelativeSource={RelativeSource Self}, Converter={StaticResource ValueToBrushConverter}}" />
    </Style>
</UserControl.Resources>
<DataGrid x:Name="dataGrid" CellStyle="{StaticResource CellStyle}">
</DataGrid>

Answer 7

        // Example: Adding a converter to a column (C#)
        Style styleReading = new Style(typeof(TextBlock));
        Setter s = new Setter();
        s.Property = TextBlock.ForegroundProperty;
        Binding b = new Binding();
        b.RelativeSource = RelativeSource.Self;
        b.Path = new PropertyPath(TextBlock.TextProperty);
        b.Converter = new ReadingForegroundSetter();
        s.Value = b;
        styleReading.Setters.Add(s);
        col.ElementStyle = styleReading;

Answer 8

在后面的代码 (VB.NET) 中执行此操作

Dim txtCol As New DataGridTextColumn

Dim style As New Style(GetType(TextBlock))
Dim tri As New Trigger With {.Property = TextBlock.TextProperty, .Value = "John"}
tri.Setters.Add(New Setter With {.Property = TextBlock.BackgroundProperty, .Value = Brushes.Green})
style.Triggers.Add(tri)

xtCol.ElementStyle = style

Answer 9

换个方式

<Style TargetType="{x:DataGridCell}" >

但请注意，这将针对您的所有单元格（您针对的是 DataGridCell 类型的所有对象） 如果您想根据单元格类型设置样式，我建议您使用DataTemplateSelector

可以在 Christian Mosers 的 DataGrid 教程中找到一个很好的示例：

http://www.wpftutorial.net/DataGrid.html#rowDetails

玩得开心:)