Question

我有一个可观察的自定义对象集合和一个公共字典变量。

我希望“ BrandName”属性充当“ Brands”词典的键，并将颜色绑定到按钮。我将如何去做呢？字典变量在类之外。

C＃代码：

private ObservableCollection<BusService> BusServicesGUI;
public Dictionary<String, Brush> Brands;

public MainWindow(Dictionary<String, BusService> busServices)
{
    InitializeComponent();
    BusServicesGUI = new ObservableCollection<BusService>(BusServices.Values);
    lstMachineFunctions.ItemsSource = BusServicesGUI;
    lstMachineFunctions.Items.Refresh();
}

C＃类：

public class BusService
{
    public string ServiceNumber { get; set; }
    public string BrandName { get; set; }
    public List<Location> Locations { get; set; }

    public BusService(string brandName, string serviceNumber)
    {
        BrandName = brandName;
        ServiceNumber = serviceNumber; 
        Locations = new List<Location>();
    }
}

XAML代码：

<StackPanel x:Name="ServiceStack">
    <ItemsControl x:Name="lstMachineFunctions">
        <ItemsControl.ItemTemplate  >
            <DataTemplate>   
                <Grid HorizontalAlignment="Stretch">
                    <usercontrols:BusServiceCard/>
                     <Button Tag="{Binding ServiceNumber}" Background="{Binding Brands[BrandName]}" Height="50" Click="ButtonCl"/>
                </Grid>
            </DataTemplate>
        </ItemsControl.ItemTemplate>
    </ItemsControl>
</StackPanel>

从XAML中可以看到，我目前的尝试是尝试Background="{Binding Brands[BrandName]}"，但是这种方法没有用，任何帮助将不胜感激。

Answer 1

您可以使用IValueConverter取消此操作。

public class BrandColorConverter : IValueConverter
{
    public Dictionary<String, Brush> Brands = new Dictionary<string, Brush>()
    {
        { "brand1", Brushes.Red },
        { "brand2", Brushes.Blue }
    };

    public object Convert(object value, Type targetType, object parameter,
            System.Globalization.CultureInfo culture)
    {
        if (!(value is BusService))
            return Binding.DoNothing;

        var busService = (BusService)value;

        if (!Brands.ContainsKey(busService.BrandName))
            return Binding.DoNothing;

        return Brands[busService.BrandName];
    }

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

在xaml中，将其添加为静态资源：

<Window.Resources>
    <local:BrandColorConverter x:Key="BrandColorConverter"/>
</Window.Resources>

并在按钮中使用它：

  <Button Tag="{Binding ServiceNumber}" 
     Background="{Binding Converter={StaticResource BrandColorConverter}}" 
     Height="50" 
     Click="ButtonCl"/>

此绑定转到当前元素，因此整个BusService对象将传递给转换器。

希望它可以解决您的问题。

如果您打算将WPF与数据绑定一起使用，我强烈建议您研究MVVM模式，因为这样会使事情更加简化。

DataBind将字典值绑定到ObservableCollection C＃-XAML

1 个答案: