Question

在我的WPF应用程序中，我具有项目控件，该控件显示一周中的日期和星期几。现在，我需要更改项目的背景颜色，即今天的日期。这是XAML代码

  <ItemsControl Grid.Column="1"
                Focusable="False" 
               ItemsSource="{Binding WeekDays}">
                <ItemsControl.ItemsPanel>
                    <ItemsPanelTemplate>
                        <StackPanel Orientation="Horizontal"/>
                    </ItemsPanelTemplate>
                </ItemsControl.ItemsPanel>
                <ItemsControl.ItemTemplate >
                    <DataTemplate>
                        <Border BorderBrush="{StaticResource GrayBrush7}"
                                BorderThickness="1,0,0,0"
                                SnapsToDevicePixels="True"
                                UseLayoutRounding="True">                                
                            <StackPanel Margin="2" 
                                      VerticalAlignment="Center">
                                <TextBlock HorizontalAlignment="Center"
                                           VerticalAlignment="Top"                                               
                                           Text="{Binding Day}"
                                           TextAlignment="Center"/>

                                <TextBlock HorizontalAlignment="Center"
                                           VerticalAlignment="Top"                                               
                                           Text="{Binding Date, 
                                                StringFormat='dd/MM/yyyy'}"
                                           TextAlignment="Center"/>
                            </StackPanel>
                        </Border>
                        </DataTemplate>
                </ItemsControl.ItemTemplate>
            </ItemsControl>

谢谢。

Answer 1

如果模型类中具有n - size + 1属性，则可以在Border Style中使用DataTrigger。像这样

IsToday

public class WeekDay
{
    public DateTime Date { get; }
    public string Day { get; }
    public bool IsToday { get; }

    public WeekDay(DateTime date)
    {
        this.Date = date;
        this.Day = date.DayOfWeek.ToString();
        this.IsToday = date.Date == DateTime.Today;
    }
}

或者，您可以使用ValueConverter将Date转换为Background。

<ItemsControl.ItemTemplate >
    <DataTemplate>
        <Border BorderBrush="{StaticResource GrayBrush7}"
                BorderThickness="1,0,0,0"
                SnapsToDevicePixels="True"
                UseLayoutRounding="True">
            <Border.Style>
                <Style TargetType="Border">
                    <Style.Triggers>
                        <DataTrigger Binding="{Binding IsToday}" Value="True">
                            <Setter Property="Background" Value="Yellow" />
                        </DataTrigger>
                    </Style.Triggers>
                </Style>
            </Border.Style>
...

public class DateToItemBackgroundConverter : IValueConverter
{
    private static readonly Brush TodayBGBrush = new SolidColorBrush(Colors.Yellow);

    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        if (value == null || !(value is DateTime))
        {
            return value;
        }

        var isToday = ((DateTime)value).Date == DateTime.Today;

        return isToday ? TodayBGBrush : null;
    }

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

请记住，如果要在TODAY更新时刷新背景，则应重建模型数据或再次通知PropertyChanged。

Answer 2

您可以在Border中添加带有DataTrigger的{{1}}样式。将您的ItemTemplate属性的Date属性与静态DateTime属性进行比较：

DateTime.Today

设置ItemsControl的背景颜色

2 个答案: