tooltip和ContentTemplateSelector的多重绑定

Question

如何将工具提示和ContentTemplateSelector多重绑定到两个或多个属性?以下是框架代码：

<Grid>
     <Grid Definitions>
      <Content Control
          **Line A** *ToolTip*//Want to bind to the same two properties as in the Text Box below and invoke the converter
          **Line B** *ContentTemplateSelector*  //Want to bind to the same two properties as in the Text Box below and invoke the converter
       />  
       **Line C** <TextBlock
          <TextBlock.Text>
                        <MultiBinding Converter="{StaticResource CountToStringConverter}">
                            <Binding Path="Property1"/>
                            <Binding Path="Property2" />
                        </MultiBinding>
            </TextBlock.Text>
        </TextBlock>
<Grid Ends>

看起来我不能使用用于文本块的MultiBinding方式。我的ContentTemplateSelector转换器继承了DataTemplateSelector控件.Any的变通方法/输入。此外，我无法对工具提示使用类似的多绑定声明

Answer 1

关于问题的第一部分，您可以像设置文本块一样设置ContentControl的ToolTip，如果ContentControl为空，则不会显示工具提示。

对于TemplateSelector，只需定义两个使用Multibinding和转换器的模板(确保使用ElementName绑定属性以避免UnserValue场景)，并将ContentControl的ContentTemplateSelector绑定到使用这两个定义的DataTemplates设置的DataTemplateSelector，下面是如何完成此操作的完整示例：

MainWindow xaml：

<Window ...
 x:Name="Main"
    Title="MainWindow" Height="450" Width="800" DataContext="{Binding RelativeSource={RelativeSource Self}}"  >
<Window.Resources>
    <local:CountToStringConverter x:Key="CountToStringConverter"/>
    <DataTemplate x:Key="FirstTemplate">
        <Grid>
            <TextBlock>
                <TextBlock.Text>
                    <MultiBinding Converter="{StaticResource CountToStringConverter}">
                        <Binding Path="DataContext.Property1" ElementName="Main"/>
                        <Binding Path="DataContext.Property2" ElementName="Main"/>
                    </MultiBinding>
                </TextBlock.Text>
            </TextBlock>
        </Grid>
    </DataTemplate>

    <DataTemplate x:Key="SecondTemplate">
        <Grid>
            <TextBlock>
                <TextBlock.Text>
                    <MultiBinding Converter="{StaticResource CountToStringConverter}">
                        <Binding Path="DataContext.Property2" ElementName="Main"/>
                        <Binding Path="DataContext.Property1" ElementName="Main"/>
                    </MultiBinding>
                </TextBlock.Text>
            </TextBlock>
        </Grid>
    </DataTemplate>
    <local:MyTemplateSelector x:Key="MyTemplateSelector" FirstDataTemplate="{StaticResource FirstTemplate}" SecondDataTemplate="{StaticResource SecondTemplate}"/>
</Window.Resources>
<Grid>
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="*"/>
            <RowDefinition Height="Auto"/>
        </Grid.RowDefinitions>
        <ContentControl ContentTemplateSelector="{StaticResource MyTemplateSelector}">
            <ContentControl.ToolTip>
                <MultiBinding Converter="{StaticResource CountToStringConverter}">
                    <Binding Path="Property1"/>
                    <Binding Path="Property2" />
                </MultiBinding>
            </ContentControl.ToolTip>
        </ContentControl>
        <TextBlock Grid.Row="1">

            <TextBlock.Text>
                <MultiBinding Converter="{StaticResource CountToStringConverter}">
                    <Binding Path="Property1"/>
                    <Binding Path="Property2" />
                </MultiBinding>
            </TextBlock.Text>
        </TextBlock>
    </Grid>
  </Grid>
 </Window>

TemplateSelector、转换器和代码背后：

public class MyTemplateSelector : DataTemplateSelector
{
    public DataTemplate FirstDataTemplate { get; set; }
    public DataTemplate SecondDataTemplate { get; set; }
    public override DataTemplate SelectTemplate(object item, DependencyObject container)
    {
        // select your template based on item
        return (new Random()).Next(2)==0?SecondDataTemplate:FirstDataTemplate;
    }
}
public class CountToStringConverter:IMultiValueConverter
{
    public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
    {
        if (values == null)
            return null;            
        return values[0]?.ToString() + values[1]?.ToString();
    }

    public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}
public partial class MainWindow : Window, INotifyPropertyChanged
{
    private string _property1;
    public string Property1
    {
        get { return _property1; }
        set
        {
            if (value == _property1) return;
            _property1 = value;
            OnPropertyChanged();
        }
    }
    private string _property2;
    public string Property2
    {
        get { return _property2; }
        set
        {
            if (value == _property2) return;
            _property2 = value;
            OnPropertyChanged();
        }
    }

    public MainWindow()
    {   
        InitializeComponent();
        Property1 = "Property 1";
        Property2 = "Property 2";
    }

    public event PropertyChangedEventHandler PropertyChanged;

    protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }

}

更新

正如我所说的，使用DataTriggers应该更容易做到这一点，所以为每个图标定义一个DataTrigger，并使用相同的多值转换器根据property1和property2的值设置ContentTemplate：

假设你有两个这样定义的DataTemplates：

<Window.Resources>
    <DataTemplate x:Key="WarningIconImageTemplate">
        <StackPanel>
            <TextBlock Text="Some Text"></TextBlock>
            <Image Source="/Icons/warningIcon.png"></Image>
        </StackPanel>
    </DataTemplate>
    <DataTemplate x:Key="CautionIconImageTemplate">
        <StackPanel>
            <TextBlock Text="Some Other Text"></TextBlock>
            <Image Source="/Icons/cautionIcon.png"></Image>
        </StackPanel>
    </DataTemplate>
    <local:CountToStringConverter x:Key="CountToStringConverter"/>
</Window.Resources>

您的DataTriggers应该如下所示：

<ContentControl>
            <ContentControl.Style>
                <Style TargetType="ContentControl">
                    <Style.Triggers>
                        <DataTrigger >
                            <DataTrigger.Binding>
                                <MultiBinding Converter="{StaticResource CountToStringConverter}">
                                    <Binding Path="Property1"/>
                                    <Binding Path="Property2" />
                                </MultiBinding>
                            </DataTrigger.Binding>
                            <DataTrigger.Value>
                                <system:String>Property 1Property 2</system:String>
                                <!--update based on your need-->
                            </DataTrigger.Value>
                            <Setter Property="ContentTemplate" Value="{StaticResource WarningIconImageTemplate}"/>
                            <Setter Property="ToolTip" Value="First ToolTip"/>
                        </DataTrigger>
                        <DataTrigger >
                            <DataTrigger.Binding>
                                <MultiBinding Converter="{StaticResource CountToStringConverter}">
                                    <Binding Path="Property1"/>
                                    <Binding Path="Property2" />
                                </MultiBinding>
                            </DataTrigger.Binding>
                            <DataTrigger.Value>
                                <system:String>Property 2Property 1</system:String>
                                <!--update based on your need-->
                            </DataTrigger.Value>
                            <Setter Property="ContentTemplate" Value="{StaticResource CautionIconImageTemplate}"/>
                            <Setter Property="ToolTip" Value="Second ToolTip"/>
                        </DataTrigger>
                    </Style.Triggers>
                </Style>
            </ContentControl.Style>
        </ContentControl>

现在，如果你想绑定图标，你可以使用ElementName绑定：

<Window.Resources>
    <DataTemplate x:Key="WarningIconImageTemplate">
        <StackPanel>
            <TextBlock Text="Some Text"></TextBlock>
            <Image Source="{Binding DataContext.WarningImageSource,ElementName=Main}" ></Image>
        </StackPanel>
    </DataTemplate>
</Window.Resources>

您也可以考虑的另一个选择是在IconImageTemplate中定义DataTrigger。

Answer 2

您可以通过以下两种方式之一编写任何属性：

以下任一项：

<ContentControl ToolTip="Some Tooltip" />

或

<ContentControl>
    <ContentControl.ToolTip>
        <MultiBinding Converter="{StaticResource CountToStringConverter}">
            <Binding Path="Property1"/>
            <Binding Path="Property2" />
        </MultiBinding>
    </ContentControl.ToolTip>
</ContentControl>