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ItemsPanelTemplate Class

Definition

Specifies the panel that the ItemsPresenter creates for the layout of the items of an ItemsControl.

public ref class ItemsPanelTemplate : System::Windows::FrameworkTemplate
public class ItemsPanelTemplate : System.Windows.FrameworkTemplate
type ItemsPanelTemplate = class
    inherit FrameworkTemplate
Public Class ItemsPanelTemplate
Inherits FrameworkTemplate
Inheritance

Examples

To create a horizontal ListBox, you can create a template that specifies a horizontal StackPanel and set it as the ItemsPanel property. The following example shows a ListBox Style that creates a horizontal ListBox.

<Style TargetType="ListBox">
  <Setter Property="ItemsPanel">
    <Setter.Value>
      <ItemsPanelTemplate>
        <StackPanel Orientation="Horizontal"
                    VerticalAlignment="Center"
                    HorizontalAlignment="Center"/>
      </ItemsPanelTemplate>
    </Setter.Value>
  </Setter>
</Style>

The following example uses a ControlTemplate to create a horizontal ListBox that has rounded corners. Note that in this example, instead of setting the ItemsPanel property as in previous example, the horizontal StackPanel is specified within the ControlTemplate. Note that the IsItemsHost property is set to true on the StackPanel, indicating that the generated items should go in the panel. When you specify it this way, the ItemsPanel cannot be replaced by the user of the control without using a ControlTemplate. Therefore, only do this if you know you wouldn't want the panel to be replaced without the use of a template.

<Style TargetType="ListBox">
  <Setter Property="Template">
    <Setter.Value>
      <ControlTemplate TargetType="ListBox">
        <Border CornerRadius="5" Background="{TemplateBinding ListBox.Background}">
          <ScrollViewer HorizontalScrollBarVisibility="Auto">
            <StackPanel Orientation="Horizontal"
                       VerticalAlignment="Center"
                       HorizontalAlignment="Center"
                       IsItemsHost="True"/>
          </ScrollViewer>
        </Border>
      </ControlTemplate>
    </Setter.Value>
  </Setter>
</Style>

Alternatively, you can do the following to achieve the same results. In this case, the ItemsPresenter creates the panel for the layout of the items based on what is specified by the ItemsPanelTemplate.

<Style TargetType="{x:Type ListBox}">
  <Setter Property="ItemsPanel">
    <Setter.Value>
      <ItemsPanelTemplate>
        <StackPanel Orientation="Horizontal"
                     VerticalAlignment="Center"
                     HorizontalAlignment="Center"/>
      </ItemsPanelTemplate>
    </Setter.Value>
  </Setter>
  <Setter Property="Template">
    <Setter.Value>
      <ControlTemplate TargetType="{x:Type ListBox}">
        <Border CornerRadius="5"
                Background="{TemplateBinding ListBox.Background}">
          <ScrollViewer HorizontalScrollBarVisibility="Auto">
            <ItemsPresenter/>
          </ScrollViewer>
        </Border>
      </ControlTemplate>
    </Setter.Value>
  </Setter>
</Style>

For an example of how to use the different styling and templating properties on the ItemsControl, see Data Templating Overview.

Remarks

The ItemsPanelTemplate specifies the panel that is used for the layout of items. GroupStyle has a Panel property that is of type ItemsPanelTemplate. ItemsControl types have an ItemsPanel property that is of type ItemsPanelTemplate.

Each ItemsControl type has a default ItemsPanelTemplate. For the ItemsControl class, the default ItemsPanel value is an ItemsPanelTemplate that specifies a StackPanel. For the ListBox, the default uses the VirtualizingStackPanel. For MenuItem, the default uses WrapPanel. For StatusBar, the default uses DockPanel.

Constructors

ItemsPanelTemplate()

Initializes an instance of the ItemsPanelTemplate class.

ItemsPanelTemplate(FrameworkElementFactory)

Initializes an instance of the ItemsPanelTemplate class with the specified template.

Properties

Dispatcher

Gets the Dispatcher this DispatcherObject is associated with.

(Inherited from DispatcherObject)
HasContent

Gets a value that indicates whether this template has optimized content.

(Inherited from FrameworkTemplate)
IsSealed

Gets a value that indicates whether this object is in an immutable state so it cannot be changed.

(Inherited from FrameworkTemplate)
Resources

Gets or sets the collection of resources that can be used within the scope of this template.

(Inherited from FrameworkTemplate)
Template

Gets or sets a reference to the object that records or plays the XAML nodes for the template when the template is defined or applied by a writer.

(Inherited from FrameworkTemplate)
VisualTree

Gets or sets the root node of the template.

(Inherited from FrameworkTemplate)

Methods

CheckAccess()

Determines whether the calling thread has access to this DispatcherObject.

(Inherited from DispatcherObject)
Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
FindName(String, FrameworkElement)

Finds the element associated with the specified name defined within this template.

(Inherited from FrameworkTemplate)
GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
LoadContent()

Loads the content of the template as an instance of an object and returns the root element of the content.

(Inherited from FrameworkTemplate)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
RegisterName(String, Object)

Registers a new name/object pair into the current name scope.

(Inherited from FrameworkTemplate)
Seal()

Locks the template so it cannot be changed.

(Inherited from FrameworkTemplate)
ShouldSerializeResources(XamlDesignerSerializationManager)

Returns a value that indicates whether serialization processes should serialize the value of the Resources property on instances of this class.

(Inherited from FrameworkTemplate)
ShouldSerializeVisualTree()

Returns a value that indicates whether serialization processes should serialize the value of the VisualTree property on instances of this class.

(Inherited from FrameworkTemplate)
ToString()

Returns a string that represents the current object.

(Inherited from Object)
UnregisterName(String)

Removes a name/object mapping from the XAML namescope.

(Inherited from FrameworkTemplate)
ValidateTemplatedParent(FrameworkElement)

Checks that the templated parent is a non-null ItemsPresenter object.

VerifyAccess()

Enforces that the calling thread has access to this DispatcherObject.

(Inherited from DispatcherObject)

Explicit Interface Implementations

INameScope.FindName(String)

Returns an object that has the provided identifying name.

(Inherited from FrameworkTemplate)
IQueryAmbient.IsAmbientPropertyAvailable(String)

Queries whether a specified ambient property is available in the current scope.

(Inherited from FrameworkTemplate)

Applies to