Question

我有一个来自WPF工具包的Accordion，其中我绑定了值

   <layoutToolkit:Accordion x:Name="myAccordion">
        <layoutToolkit:Accordion.ItemTemplate>
            <DataTemplate>
                <TextBlock x:Name="myHeader" Text="{Binding Date}" />
                <DataTemplate.Resources>
                  <local:BeforeTodayConverter x:Key="IsBeforeToday" />
                </DataTemplate.Resources>
                <DataTemplate.Triggers>
                <DataTrigger 
                    Binding="{Binding Date, Converter={StaticResource IsBeforeToday}}" 
                    Value="True">
                 <Setter 
                    TargetName="myHeader" 
                    Property="Foreground" 
                    Value="Blue" />
                </DataTrigger>
                </DataTemplate.Triggers>
            </DataTemplate>
        </layoutToolkit:Accordion.ItemTemplate>
        <layoutToolkit:Accordion.ContentTemplate>
            <DataTemplate>
               //not important
            </DataTemplate>
        </layoutToolkit:Accordion.ContentTemplate>
    </layoutToolkit:Accordion>

转换器：

public class BeforeTodayConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
    if (!(value is DateTime))
    {
        return false;
    }

    return ((DateTime)value).CompareTo(DateTime.Today) < 0;
}

public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
    throw new NotImplementedException();
}

} 我想要的是改变文本块的前景＆＃34; myHeader＆＃34;取决于约束日期。如果日期是从今天开始的日期，我希望它是蓝色的，如果日期是从今天开始的日期，我希望它是红色的。

有没有办法解决这个问题？

Answer 1

写一个值转换器来比较日期：

public class BeforeTodayConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        if (!(value is DateTime))
        {
            return false;
        }

        return ((DateTime)value).CompareTo(DateTime.Today) < 0;
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

并在模板中使用它：

<DataTemplate>
    <TextBlock 
        x:Name="myHeader" 
        Text="{Binding Date}" 
        Foreground="Red" 
        />
    <DataTemplate.Resources>
        <local:BeforeTodayConverter x:Key="IsBeforeToday" />
    </DataTemplate.Resources>
    <DataTemplate.Triggers>
        <DataTrigger 
            Binding="{Binding Date, Converter={StaticResource IsBeforeToday}}" 
            Value="True"
            >
            <Setter 
                TargetName="myHeader" 
                Property="Foreground" 
                Value="Blue" 
                />
        </DataTrigger>
    </DataTemplate.Triggers>
</DataTemplate>

根据日期限制更改DataTemplate中的Textblock前景

1 个答案: