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DataTemplate.Triggers Property

Definition

Gets a collection of triggers that apply property values or perform actions based on one or more conditions.

public:
 property System::Windows::TriggerCollection ^ Triggers { System::Windows::TriggerCollection ^ get(); };
[System.Windows.Markup.DependsOn("VisualTree")]
public System.Windows.TriggerCollection Triggers { get; }
[System.Windows.Markup.DependsOn("VisualTree")]
[System.Windows.Markup.DependsOn("Template")]
public System.Windows.TriggerCollection Triggers { get; }
[<System.Windows.Markup.DependsOn("VisualTree")>]
member this.Triggers : System.Windows.TriggerCollection
[<System.Windows.Markup.DependsOn("VisualTree")>]
[<System.Windows.Markup.DependsOn("Template")>]
member this.Triggers : System.Windows.TriggerCollection
Public ReadOnly Property Triggers As TriggerCollection

Property Value

A collection of trigger objects. The default value is null.

Attributes

Examples

The following DataTemplate demonstrates the use of the Triggers property.

<DataTemplate DataType="{x:Type src:AuctionItem}">
    <Border BorderThickness="1" BorderBrush="Gray"
            Padding="7" Name="border" Margin="3" Width="500">
        <Grid>
          <Grid.RowDefinitions>
            <RowDefinition/>
            <RowDefinition/>
            <RowDefinition/>
            <RowDefinition/>
          </Grid.RowDefinitions>
          <Grid.ColumnDefinitions>
            <ColumnDefinition Width="20"/>
            <ColumnDefinition Width="86"/>
            <ColumnDefinition Width="*"/>
          </Grid.ColumnDefinitions>
              
            <Polygon Grid.Row="0" Grid.Column="0" Grid.RowSpan="4"
                     Fill="Yellow" Stroke="Black" StrokeThickness="1"
                     StrokeLineJoin="Round" Width="20" Height="20"
                     Stretch="Fill"
                     Points="9,2 11,7 17,7 12,10 14,15 9,12 4,15 6,10 1,7 7,7"
                     Visibility="Hidden" Name="star"/>

            <TextBlock Grid.Row="0" Grid.Column="1" Margin="0,0,8,0"
                       Name="descriptionTitle"
                       Style="{StaticResource smallTitleStyle}">Description:</TextBlock>
            <TextBlock Name="DescriptionDTDataType" Grid.Row="0" Grid.Column="2" 
                Text="{Binding Path=Description}" 
                Style="{StaticResource textStyleTextBlock}"/>

            <TextBlock Grid.Row="1" Grid.Column="1" Margin="0,0,8,0"
                       Name="currentPriceTitle"
                       Style="{StaticResource smallTitleStyle}">Current Price:</TextBlock>
            <StackPanel Grid.Row="1" Grid.Column="2" Orientation="Horizontal">
                <TextBlock Text="$" Style="{StaticResource textStyleTextBlock}"/>
                <TextBlock Name="CurrentPriceDTDataType" 
                    Text="{Binding Path=CurrentPrice}" 
                    Style="{StaticResource textStyleTextBlock}"/>
            </StackPanel>
        </Grid>
    </Border>
    <DataTemplate.Triggers>
        <DataTrigger Binding="{Binding Path=SpecialFeatures}">
            <DataTrigger.Value>
                <src:SpecialFeatures>Color</src:SpecialFeatures>
            </DataTrigger.Value>
          <DataTrigger.Setters>
            <Setter Property="BorderBrush" Value="DodgerBlue" TargetName="border" />
            <Setter Property="Foreground" Value="Navy" TargetName="descriptionTitle" />
            <Setter Property="Foreground" Value="Navy" TargetName="currentPriceTitle" />
            <Setter Property="BorderThickness" Value="3" TargetName="border" />
            <Setter Property="Padding" Value="5" TargetName="border" />
          </DataTrigger.Setters>
        </DataTrigger>
        <DataTrigger Binding="{Binding Path=SpecialFeatures}">
            <DataTrigger.Value>
                <src:SpecialFeatures>Highlight</src:SpecialFeatures>
            </DataTrigger.Value>
            <Setter Property="BorderBrush" Value="Orange" TargetName="border" />
            <Setter Property="Foreground" Value="Navy" TargetName="descriptionTitle" />
            <Setter Property="Foreground" Value="Navy" TargetName="currentPriceTitle" />
            <Setter Property="Visibility" Value="Visible" TargetName="star" />
            <Setter Property="BorderThickness" Value="3" TargetName="border" />
            <Setter Property="Padding" Value="5" TargetName="border" />
        </DataTrigger>
    </DataTemplate.Triggers>
</DataTemplate>

For the complete sample, see Data Binding Demo.

Remarks

If you are creating triggers within a data template, the setters of the triggers should be setting properties that are within the scope of the data template. Otherwise, it may be more suitable to create triggers using a style that targets the type that contains the data. For example, if you are binding a ListBox control, the containers are ListBoxItem objects. If you are using triggers to set properties that are not within the scope of the DataTemplate, then it may be more suitable to create a ListBoxItem style and create triggers within that style. For more information, see What Belongs in a DataTemplate? in the Data Templating Overview.

Note

This property can only be set in Extensible Application Markup Language (XAML) via the collection syntax shown, or by accessing the collection object and using its various methods such as Add. The property to access the collection object itself is read-only, the collection itself is read-write.

XAML Property Element Usage

<object>  
  <object.Triggers>  
    OneOrMoreTriggers  
  </object.Triggers>  
</object>  

XAML Values

OneOrMoreTriggers
Zero or more TriggerBase objects.

Applies to

See also