如何在 Windows Phone 8 中选择列表框项时更改椭圆的笔划

您可以将INotifyPropertyChanged实现到模型中并添加

public class Model : INotifyPropertyChanged
{
    private bool _isSelected;
    public string PHOTO { get; set; }
    public string NAME { get; set; }
    public string DISTANCE { get; set; }
    public bool IsSelected
    {
        get
        {
            return _isSelected;
        }
        set
        {
            if (value != _isSelected)
            {
                _isSelected = value;
                RaisePropertyChanged();
            }
        }
    }
    public event PropertyChangedEventHandler PropertyChanged;
    private void RaisePropertyChanged([CallerMemberName] string propertyName = null)
    {
        var propertyChanged = Volatile.Read(ref PropertyChanged);
        if (propertyChanged != null)
        {
            propertyChanged(this, new PropertyChangedEventArgs(propertyName));
        }
    }
}

因此，在OwnerList_SelectionChanged您应该更改此属性

    private void OwnerList_SelectionChanged(object sender, SelectionChangedEventArgs e)
    {
        if (e.AddedItems != null && e.AddedItems.Count > 0)
        {
            var addedItem = e.AddedItems.Cast<Model>().ToList();
            foreach(var item in addedItem)
            {
                item.IsSelected = true;
            }
        }
        if (e.RemovedItems != null && e.RemovedItems.Count > 0)
        {
            var removedItems = e.RemovedItems.Cast<Model>().ToList();
            foreach (var item in removedItems)
            {
                item.IsSelected = false;
            }
        }
    }

为Stroke创建简单的转换器

public class EllipseStrokeConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        var result = new SolidColorBrush(Colors.Blue);
        if ((bool)value)
        {
            result = new SolidColorBrush(Colors.Red);
        }
        return result;
    }
    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

并在模板中使用它

  <local:EllipseStrokeConverter x:Key="EllipseStrokeConverter"/>
    <DataTemplate x:Key="OwnerListTemplate">
        <StackPanel Margin="20,0,20,0">
            <Ellipse Height="120"
                 Width="120"
                 Margin="4"
                 Stroke="{Binding IsSelected, Converter={StaticResource EllipseStrokeConverter}}"
                 StrokeThickness="2">
                <Ellipse.Fill>
                    <ImageBrush ImageSource="{Binding PHOTO, Converter={StaticResource Imageconverter}}"/>
                </Ellipse.Fill>
            </Ellipse>
            <TextBlock x:Name="OwnerName"
                   Text="{Binding NAME}"
                   FontSize="22"
                   Foreground="Gray"
                   FontWeight="Bold"
                   HorizontalAlignment="Center"
                   VerticalAlignment="Center"/>
            <TextBlock x:Name="distance"
                   Text="{Binding DISTANCE}"
                   FontSize="20"
                   Foreground="Gray"
                   HorizontalAlignment="Center"
                   VerticalAlignment="Center"/>
        </StackPanel>
    </DataTemplate>

更新

我知道另一种无需C#操纵的解决方案。在我们的ListBoxItem中，我们从ContentControl中选择一些属性，这些属性将在DataTemplate中描述我们的属性的逻辑，并通过Binding使用此属性值。

<Style x:Key="ListBoxItemStyle" TargetType="ListBoxItem">
    <Setter Property="Background" Value="Transparent"/>
    <Setter Property="BorderThickness" Value="0"/>
    <Setter Property="BorderBrush" Value="Transparent"/>
    <Setter Property="Padding" Value="0"/>
    <Setter Property="HorizontalContentAlignment" Value="Left"/>
    <Setter Property="VerticalContentAlignment" Value="Top"/>
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="ListBoxItem">
                <Border x:Name="LayoutRoot" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" HorizontalAlignment="{TemplateBinding HorizontalAlignment}" VerticalAlignment="{TemplateBinding VerticalAlignment}">
                    <VisualStateManager.VisualStateGroups>
                        <VisualStateGroup x:Name="CommonStates">
                            <VisualState x:Name="Normal"/>
                            <VisualState x:Name="MouseOver"/>
                            <VisualState x:Name="Disabled">
                                <Storyboard>
                                    <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Background" Storyboard.TargetName="LayoutRoot">
                                        <DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource TransparentBrush}"/>
                                    </ObjectAnimationUsingKeyFrames>
                                    <DoubleAnimation Duration="0" To=".5" Storyboard.TargetProperty="Opacity" Storyboard.TargetName="ContentContainer"/>
                                </Storyboard>
                            </VisualState>
                        </VisualStateGroup>
                        <VisualStateGroup x:Name="SelectionStates">
                            <VisualState x:Name="Unselected"/>
                            <VisualState x:Name="Selected">
                                <Storyboard>
                                    <ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentContainer"
                                                                    Storyboard.TargetProperty="BorderBrush">
                                        <DiscreteObjectKeyFrame KeyTime="0" Value="Yellow"/>
                                    </ObjectAnimationUsingKeyFrames>
                                </Storyboard>
                            </VisualState>
                        </VisualStateGroup>
                    </VisualStateManager.VisualStateGroups>
                    <ContentControl x:Name="ContentContainer"
                                    BorderBrush="Blue"
                                    ContentTemplate="{TemplateBinding ContentTemplate}"
                                    Content="{TemplateBinding Content}"
                                    Foreground="{TemplateBinding Foreground}"
                                    HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" 
                                    Margin="{TemplateBinding Padding}"
                                    VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"/>
                </Border>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

查看Selected视觉状态名称，我们在其中更改BorderBrush以这种方式在DataTemplate中使用的属性值

Stroke="{Binding BorderBrush, ElementName=ContentContainer}"