將一個按鈕的標籤屬性設置爲一個整數值並觸發一個觸發器

Question

我想要做類似下面的事情，但它不起作用。我想使用一個數據觸發器來設置一個整數（或任何類型）值到我在我的數據模板中定義的按鈕的標籤屬性。然後在按鈕的圖像樣式中，當相應的值設置爲按鈕的標籤屬性時觸發一個觸發器。但它似乎並沒有這樣工作。如果我設置了x：Null值，我可以觸發該觸發器，這意味着邏輯正常。但是設置一個值如0或1不會觸發觸發器。任何解決方案

<DataTemplate x:Key="SomeDataTemplateofSomeType"> 

<Button x:Name="ButtonVisible"> 
    <Button.Template> 
     <ControlTemplate TargetType="Button"> 
      <Image x:Name="FxImage"> 
        <Image.Style> 
         <Style TargetType="{x:Type Image}"> 
         <Style.Triggers> 
          <DataTrigger Binding="{Binding Tag, RelativeSource={RelativeSource TemplatedParent},UpdateSourceTrigger=PropertyChanged}" Value="0"> 
           <Setter Property="Source" Value="/Resources/controls/images/fxiconsnone.png" /> 
          </DataTrigger> 
         </Style.Triggers> 
         </Style> 
       </Image.Style> 
      </Image> 
     </ControlTemplate> 
    </Button.Template> 
</Button> 

<DataTemplate.Triggers> 
<DataTrigger Binding="{Binding Path=IsVisible, Value="True"> 
    <Setter Property="Tag" TargetName="ButtonVisible" Value="1" /> 
</DataTrigger> 

<DataTrigger Binding="{Binding Path=IsVisible, Value="False"> 
    <Setter Property="Tag" TargetName="ButtonVisible" Value="0" /> 
</DataTrigger> 
</DataTemplate.Triggers> 
</Datatemplate> 

Answer 1

您綁定到Image的DataContext，而不是到模板Button

綁定到TemplatedParent代替。

在旁註中，沒有必要使用兩個DataTriggers來表示真和假。做到這一點，而不是

<Button x:Name="ButtonVisible" Tag="1"> 

只保留了DataTriggers

<DataTrigger Binding="{Binding Path=IsVisible}" Value="False"> 
    <Setter Property="Tag" TargetName="ButtonVisible" Value="0" /> 
</DataTrigger> 

---

例之一，添加以下MainWindow.xaml

<StackPanel> 
    <StackPanel.Resources> 
     <DataTemplate x:Key="SomeDataTemplateofSomeType"> 
      <Button x:Name="ButtonVisible"> 
       <Button.Template> 
        <ControlTemplate TargetType="Button"> 
         <Image x:Name="FxImage"> 
          <Image.Style> 
           <Style TargetType="{x:Type Image}"> 
            <Style.Triggers> 
             <DataTrigger Binding="{Binding Tag, RelativeSource={RelativeSource TemplatedParent},UpdateSourceTrigger=PropertyChanged}" Value="0"> 
              <Setter Property="Source" Value="YourImageSource" /> 
             </DataTrigger> 
            </Style.Triggers> 
           </Style> 
          </Image.Style> 
         </Image> 
        </ControlTemplate> 
       </Button.Template> 
      </Button> 
      <DataTemplate.Triggers> 
       <DataTrigger Binding="{Binding Path=IsVisible}" Value="True"> 
        <Setter Property="Tag" TargetName="ButtonVisible" Value="1" /> 
       </DataTrigger> 
       <DataTrigger Binding="{Binding Path=IsVisible}" Value="False"> 
        <Setter Property="Tag" TargetName="ButtonVisible" Value="0" /> 
       </DataTrigger> 
      </DataTemplate.Triggers> 
     </DataTemplate> 
    </StackPanel.Resources> 
    <ContentControl Content="{Binding MySource}" 
        ContentTemplate="{StaticResource SomeDataTemplateofSomeType}"/> 
    <ToggleButton IsChecked="{Binding Path=MySource.IsVisible, Mode=TwoWay}" Content="IsChecked?"/> 
</StackPanel> 

MainWindow.xaml.cs

public partial class MainWindow : Window 
{ 
    public MainWindow() 
    { 
     InitializeComponent(); 
     MySource = new MySource(); 

     this.DataContext = this; 
    } 
    public MySource MySource 
    { 
     get; 
     set; 
    } 
} 
public class MySource : INotifyPropertyChanged 
{ 
    private bool m_isVisible; 
    public bool IsVisible 
    { 
     get { return m_isVisible; } 
     set 
     { 
      m_isVisible = value; 
      OnPropertyChanged("IsVisible"); 
     } 
    } 

    public event PropertyChangedEventHandler PropertyChanged; 
    private void OnPropertyChanged(string propertyName) 
    { 
     if (PropertyChanged != null) 
     { 
      PropertyChanged(this, new PropertyChangedEventArgs(propertyName)); 
     } 
    } 
}