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MultiDataTrigger.Conditions Property

  • Reference

Definition

Namespace:
System.Windows
Assembly:
PresentationFramework.dll

Gets a collection of Condition objects. Changes to property values are applied when all the conditions in the collection are met.

public:
 property System::Windows::ConditionCollection ^ Conditions { System::Windows::ConditionCollection ^ get(); };
public System.Windows.ConditionCollection Conditions { get; }
member this.Conditions : System.Windows.ConditionCollection
Public ReadOnly Property Conditions As ConditionCollection

Property Value

ConditionCollection

A collection of Condition objects. The default is an empty collection.

Examples

In the following example, the ItemsSource property of the ListBox is bound to Places, an ObservableCollection<T> of Place objects. Place objects have properties Name and State. The definition of Place and Places are not shown.

Each ListBoxItem of the ListBox displays a Place object. The Style in the example is applied to each ListBoxItem. The Condition elements of the MultiDataTrigger specify that if the Name and State of the Place data item are Portland and OR respectively, then the background of corresponding ListBoxItem is set to Cyan.

<Window.Resources>
  <c:Places x:Key="PlacesData"/>

  <Style TargetType="ListBoxItem">
    <Style.Triggers>
      <DataTrigger Binding="{Binding Path=State}" Value="WA">
        <Setter Property="Foreground" Value="Red" />
      </DataTrigger>	
      <MultiDataTrigger>
        <MultiDataTrigger.Conditions>
          <Condition Binding="{Binding Path=Name}" Value="Portland" />
          <Condition Binding="{Binding Path=State}" Value="OR" />
        </MultiDataTrigger.Conditions>
        <Setter Property="Background" Value="Cyan" />
      </MultiDataTrigger>
    </Style.Triggers>
  </Style>

  <DataTemplate DataType="{x:Type c:Place}">
    <Canvas Width="160" Height="20">
      <TextBlock FontSize="12"
             Width="130" Canvas.Left="0" Text="{Binding Path=Name}"/>
      <TextBlock FontSize="12" Width="30"
                 Canvas.Left="130" Text="{Binding Path=State}"/>
    </Canvas>
  </DataTemplate>
</Window.Resources>

<StackPanel>
  <TextBlock FontSize="18" Margin="5" FontWeight="Bold"
    HorizontalAlignment="Center">Data Trigger Sample</TextBlock>
  <ListBox Width="180" HorizontalAlignment="Center" Background="Honeydew"
    ItemsSource="{Binding Source={StaticResource PlacesData}}"/>
</StackPanel>

Remarks

A MultiDataTrigger object is similar to a MultiTrigger, except that the conditions of a MultiDataTrigger are based on property values of bound data instead of those of a UIElement. In a MultiDataTrigger, a condition is met when the property value of the data item matches the specified Value. That value is first converted to the type of the value of the binding, if possible, and then the two values are compared using the Object.Equals method. The MultiTrigger applies the associated setters or actions when all of the conditions are true (binary AND operation).

For a MultiDataTrigger, each condition in the collection must set both the Binding and Value properties. For more information, see Binding.

XAML Property Element Usage

<object>  
  <object.Conditions>  
    zeroOrMoreConditions  
  </object.Conditions>  
</object>

XAML Values

zeroOrMoreConditions
Zero or more Condition objects.

Applies to

See also