工具提示和内容模板选择器的多重绑定

Question

如何将工具提示和内容模板选择器多重绑定到两个或多个属性？这是骨架代码：

<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>

看起来我不能使用我用于文本块的多重绑定方式。我的 ContentTemplateSelector 转换器继承了 DataTemplateSelector 控件。感谢任何解决方法/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情况)，并将ContentControl的ContentTemplateSelector绑定到使用两个定义的DataTemplates设置的DataTemplateSelector，以下是如何执行此操作的完整示例：

主窗口 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>

模板选择器、转换器和代码隐藏：

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，使用 DataTrigger 应该更容易做到这一点，因此请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：

假设您有两个数据模板定义如下：

<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>

您的数据触发器应如下所示：

<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，如果要绑定图标，可以随时使用ElementName绑定来执行此操作：

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

您可能还考虑的另一个选项是在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：

也：

<ContentControl ToolTip="Some Tooltip" />

或

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