ComboBoxItem Class
[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]
Represents a selectable item contained in a ComboBox control.
Assembly: System.Windows (in System.Windows.dll)
XMLNS for XAML: Not mapped to an xmlns.
The ComboBoxItem type exposes the following members.
| Name | Description | |
|---|---|---|
 | ActualHeight | Gets the rendered height of a FrameworkElement. (Inherited from FrameworkElement.) |
| ActualWidth | Gets the rendered width of a FrameworkElement. (Inherited from FrameworkElement.) |
| AllowDrop | Gets or sets a value that determines whether this UIElement can be a drop target for purposes of drag-and-drop operations. (Inherited from UIElement.) |
| Background | (Inherited from Control.) |
| BorderBrush | (Inherited from Control.) |
| BorderThickness | (Inherited from Control.) |
| CacheMode | Gets or sets a value that indicates that rendered content should be cached when possible. (Inherited from UIElement.) |
| CharacterSpacing | (Inherited from Control.) |
| Clip | Gets or sets the Geometry used to define the outline of the contents of a UIElement. (Inherited from UIElement.) |
| Content | Gets or sets the value of the ContentControl dependency property. (Inherited from ContentControl.) |
| ContentTemplate | Gets or sets the data template that is used to display the content of the ContentControl. (Inherited from ContentControl.) |
| Cursor | Infrastructure. Gets or sets the cursor image that displays while the pointer is over a FrameworkElement. (Inherited from FrameworkElement.) |
| DataContext | Gets or sets the data context for a FrameworkElement when it participates in data binding. (Inherited from FrameworkElement.) |
 | DefaultStyleKey | (Inherited from Control.) |
| DesiredSize | Gets the size that this UIElement computed during the measure pass of the layout process. (Inherited from UIElement.) |
| Dispatcher | Gets the Dispatcher this object is associated with. (Inherited from DependencyObject.) |
| FlowDirection | Gets or sets the direction that text and other user interface elements flow within any parent element that controls their layout. (Inherited from FrameworkElement.) |
| FontFamily | (Inherited from Control.) |
| FontSize | (Inherited from Control.) |
| FontStretch | (Inherited from Control.) |
| FontStyle | (Inherited from Control.) |
| FontWeight | (Inherited from Control.) |
| Foreground | (Inherited from Control.) |
| Height | Gets or sets the suggested height of a FrameworkElement. (Inherited from FrameworkElement.) |
| HorizontalAlignment | Gets or sets the horizontal alignment characteristics that are applied to a FrameworkElement when it is composed in a layout parent, such as a panel or items control. (Inherited from FrameworkElement.) |
| HorizontalContentAlignment | (Inherited from Control.) |
| IsEnabled | (Inherited from Control.) |
| IsHitTestVisible | Gets or sets whether the contained area of this UIElement can return true values for hit testing. (Inherited from UIElement.) |
| IsSelected | Gets or sets a value that indicates whether a ListBoxItem is selected. (Inherited from ListBoxItem.) |
| IsTabStop | (Inherited from Control.) |
| Language | Gets or sets localization/globalization language information that applies to a FrameworkElement. (Inherited from FrameworkElement.) |
| Margin | Gets or sets the outer margin of a FrameworkElement. (Inherited from FrameworkElement.) |
| MaxHeight | Gets or sets the maximum height constraint of a FrameworkElement. (Inherited from FrameworkElement.) |
| MaxWidth | Gets or sets the maximum width constraint of a FrameworkElement. (Inherited from FrameworkElement.) |
| MinHeight | Gets or sets the minimum height constraint of a FrameworkElement. (Inherited from FrameworkElement.) |
| MinWidth | Gets or sets the minimum width constraint of a FrameworkElement. (Inherited from FrameworkElement.) |
| Name | Gets or sets the identifying name of the object. When a XAML processor creates the object tree from XAML markup, run-time code can refer to the XAML-declared object by this name. (Inherited from FrameworkElement.) |
| Opacity | Gets or sets the degree of the object's opacity. (Inherited from UIElement.) |
| OpacityMask | Gets or sets the brush used to alter the opacity of regions of this object. (Inherited from UIElement.) |
| Padding | (Inherited from Control.) |
| Parent | Gets the parent object of this FrameworkElement in the object tree. (Inherited from FrameworkElement.) |
| Projection | Gets or sets the perspective projection (3-D effect) to apply when rendering this UIElement. (Inherited from UIElement.) |
| RenderSize | Gets the final render size of a UIElement. (Inherited from UIElement.) |
| RenderTransform | Gets or sets transform information that affects the rendering position of a UIElement. (Inherited from UIElement.) |
| RenderTransformOrigin | Gets or sets the origin point of any possible render transform declared by RenderTransform, relative to the bounds of the UIElement. (Inherited from UIElement.) |
| Resources | Gets the locally defined resource dictionary. In XAML, you can establish resource items as child object elements of a frameworkElement.Resources property element, through XAML implicit collection syntax. (Inherited from FrameworkElement.) |
| Style | Gets or sets an instance Style that is applied for this object during rendering. (Inherited from FrameworkElement.) |
| TabIndex | (Inherited from Control.) |
| TabNavigation | (Inherited from Control.) |
| Tag | Gets or sets an arbitrary object value that can be used to store custom information about this object. (Inherited from FrameworkElement.) |
| Template | (Inherited from Control.) |
| Triggers | Gets the collection of triggers for animations that are defined for a FrameworkElement. (Inherited from FrameworkElement.) |
| UseLayoutRounding | Gets or sets a value that determines whether rendering for the object and its visual subtree should use rounding behavior that aligns rendering to whole pixels. (Inherited from UIElement.) |
| UseOptimizedManipulationRouting | Gets or sets a value that indicates whether the system should handle input events or whether the FrameworkElement should handle input events. (Inherited from FrameworkElement.) |
| VerticalAlignment | Gets or sets the vertical alignment characteristics that are applied to a FrameworkElement when it is composed in a parent object such as a panel or items control. (Inherited from FrameworkElement.) |
| VerticalContentAlignment | (Inherited from Control.) |
| Visibility | Gets or sets the visibility of a UIElement. A UIElement that is not visible does not render and does not communicate its desired size to layout. (Inherited from UIElement.) |
| Width | Gets or sets the width of a FrameworkElement. (Inherited from FrameworkElement.) |
| Name | Description | |
|---|---|---|
 | AddHandler | Adds a routed event handler for a specified routed event, adding the handler to the handler collection on the current element. Specify handledEventsToo as true to have the provided handler be invoked for routed event that had already been marked as handled by another element along the event route. (Inherited from UIElement.) |
| ApplyTemplate | (Inherited from Control.) |
| Arrange | Positions child objects and determines a size for a UIElement. Parent objects that implement custom layout for their child elements should call this method from their layout override implementations to form a recursive layout update. (Inherited from UIElement.) |
 | ArrangeOverride | Provides the behavior for the Arrange pass of Windows Phone layout. Classes can override this method to define their own Arrange pass behavior. (Inherited from FrameworkElement.) |
| CaptureMouse | Sets touch capture to a UIElement. (Inherited from UIElement.) |
| CheckAccess | Determines whether the calling thread has access to this object. (Inherited from DependencyObject.) |
| ClearValue | Clears the local value of a dependency property. (Inherited from DependencyObject.) |
| Equals(Object) | Determines whether the specified Object is equal to the current Object. (Inherited from Object.) |
| Finalize | Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.) |
| FindName | Retrieves an object that has the specified identifier name. (Inherited from FrameworkElement.) |
| Focus | (Inherited from Control.) |
| GetAnimationBaseValue | Returns any base value established for a Windows Phone dependency property, which would apply in cases where an animation is not active. (Inherited from DependencyObject.) |
| GetBindingExpression | Retrieves the BindingExpression for a dependency property where a binding is established. (Inherited from FrameworkElement.) |
| GetHashCode | Serves as a hash function for a particular type. (Inherited from Object.) |
| GetTemplateChild | (Inherited from Control.) |
| GetType | Gets the Type of the current instance. (Inherited from Object.) |
| GetValue | Returns the current effective value of a dependency property from a DependencyObject. (Inherited from DependencyObject.) |
| InvalidateArrange | Invalidates the arrange state (layout) for a UIElement. After the invalidation, the UIElement will have its layout updated, which will occur asynchronously. (Inherited from UIElement.) |
| InvalidateMeasure | Invalidates the measurement state (layout) for a UIElement. (Inherited from UIElement.) |
| Measure | Updates the DesiredSize of a UIElement. Typically, objects that implement custom layout for their layout children call this method from their own MeasureOverride implementations to form a recursive layout update. (Inherited from UIElement.) |
| MeasureOverride | Provides the behavior for the Measure pass of Windows Phone layout. Classes can override this method to define their own Measure pass behavior. (Inherited from FrameworkElement.) |
| MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object.) |
| OnApplyTemplate | Builds the visual tree for the ListBoxItem control when a new template is applied. (Inherited from ListBoxItem.) |
| OnContentChanged | Called when the value of the Content property changes. (Inherited from ContentControl.) |
| OnCreateAutomationPeer | Returns a ListBoxItemAutomationPeer for the Windows Phone automation infrastructure. (Inherited from ListBoxItem.) |
| OnDoubleTap | (Inherited from Control.) |
| OnDragEnter | (Inherited from Control.) |
| OnDragLeave | (Inherited from Control.) |
| OnDragOver | (Inherited from Control.) |
| OnDrop | (Inherited from Control.) |
| OnGotFocus | Provides handling for the GotFocus event. (Inherited from ListBoxItem.) |
| OnHold | (Inherited from Control.) |
| OnKeyDown | (Inherited from Control.) |
| OnKeyUp | (Inherited from Control.) |
| OnLostFocus | Provides handling for the LostFocus event. (Inherited from ListBoxItem.) |
| OnLostMouseCapture | (Inherited from Control.) |
| OnManipulationCompleted | Called when the ManipulationCompletedevent occurs. (Overrides ListBoxItem::OnManipulationCompleted(ManipulationCompletedEventArgs).) |
| OnManipulationDelta | (Inherited from Control.) |
| OnManipulationStarted | Called when the ManipulationStarted event occurs. (Overrides ListBoxItem::OnManipulationStarted(ManipulationStartedEventArgs).) |
| OnMouseEnter | Infrastructure. Provides handling for the MouseEnter event. (Inherited from ListBoxItem.) |
| OnMouseLeave | Infrastructure. Provides handling for the MouseLeave event. (Inherited from ListBoxItem.) |
| OnMouseLeftButtonDown | Infrastructure. Provides handling for the MouseLeftButtonDown event. (Inherited from ListBoxItem.) |
| OnMouseLeftButtonUp | (Inherited from Control.) |
| OnMouseMove | (Inherited from Control.) |
| OnMouseRightButtonDown | (Inherited from Control.) |
| OnMouseRightButtonUp | (Inherited from Control.) |
| OnMouseWheel | (Inherited from Control.) |
| OnTap | (Inherited from Control.) |
| OnTextInput | (Inherited from Control.) |
| OnTextInputStart | (Inherited from Control.) |
| OnTextInputUpdate | (Inherited from Control.) |
| ReadLocalValue | Returns the local value of a dependency property, if a local value is set. (Inherited from DependencyObject.) |
| ReleaseMouseCapture | Removes touch capture from a UIElement. After this call, typically no object holds touch capture. (Inherited from UIElement.) |
| RemoveHandler | Removes the specified routed event handler from this UIElement. (Inherited from UIElement.) |
| SetBinding | Attaches a binding to a FrameworkElement, using the provided binding object, and returns a BindingExpressionBase for possible later use. (Inherited from FrameworkElement.) |
| SetValue | Sets the local value of a dependency property on a DependencyObject. (Inherited from DependencyObject.) |
| ToString | Returns a string that represents the current object. (Inherited from Object.) |
| TransformToVisual | Returns a transform object that can be used to transform coordinates from the UIElement to the specified object. (Inherited from UIElement.) |
| UpdateLayout | Ensures that all positions of child objects of a UIElement are properly updated for layout. (Inherited from UIElement.) |
| Name | Description | |
|---|---|---|
 | BindingValidationError | Occurs when a data validation error is reported by a binding source. (Inherited from FrameworkElement.) |
| DoubleTap | Occurs when a DoubleTap gesture is committed while over this UIElement. (Inherited from UIElement.) |
| GotFocus | Occurs when a UIElement receives focus. (Inherited from UIElement.) |
| Hold | Occurs when a Hold gesture is committed while over this UIElement. (Inherited from UIElement.) |
| IsEnabledChanged | (Inherited from Control.) |
| KeyDown | Occurs when a keyboard key is pressed while the UIElement has focus. (Inherited from UIElement.) |
| KeyUp | Occurs when a keyboard key is released while the UIElement has focus. (Inherited from UIElement.) |
| LayoutUpdated | Occurs when the layout of the Windows Phone visual tree changes. (Inherited from FrameworkElement.) |
| Loaded | Occurs when a FrameworkElement has been constructed and added to the object tree. (Inherited from FrameworkElement.) |
| LostFocus | Occurs when a UIElement loses focus. (Inherited from UIElement.) |
| LostMouseCapture | Occurs when the UIElement loses touch capture. (Inherited from UIElement.) |
| ManipulationCompleted | Occurs when a manipulation and inertia on the UIElement is complete. (Inherited from UIElement.) |
| ManipulationDelta | Occurs when the input device changes position during a manipulation. (Inherited from UIElement.) |
| ManipulationStarted | Occurs when an input device begins a manipulation on the UIElement. (Inherited from UIElement.) |
| MouseEnter | Occurs when a screen tap occurs within the bounding area of a UIElement. (Inherited from UIElement.) |
| MouseLeave | Occurs when a touch event occurs outside the bounding area of a UIElement. (Inherited from UIElement.) |
| MouseLeftButtonDown | Occurs when a UIElement is tapped. (Inherited from UIElement.) |
| MouseLeftButtonUp | Occurs when the finger is lifted off of a UIElement (or while a UIElement holds touch capture). (Inherited from UIElement.) |
| MouseMove | Occurs when the coordinate position of the finger on the screen while touching a UIElement (or while a UIElement holds touch capture). (Inherited from UIElement.) |
| MouseWheel | Infrastructure. Occurs when the user rotates the mouse wheel while the mouse pointer is over a UIElement, or the UIElement has focus. (Inherited from UIElement.) |
| SizeChanged | Occurs when either the ActualHeight or the ActualWidth properties change value on a FrameworkElement. (Inherited from FrameworkElement.) |
| Tap | Occurs when a Tap gesture is committed while over this UIElement. (Inherited from UIElement.) |
| TextInput | Occurs when a UI element gets text in a device-independent manner. (Inherited from UIElement.) |
| TextInputStart | Occurs when a UI element initially gets text in a device-independent manner. (Inherited from UIElement.) |
| TextInputUpdate | Occurs when text continues to be composed via an input method editor (IME). (Inherited from UIElement.) |
| Unloaded | Occurs when this object is no longer connected to the main object tree. (Inherited from FrameworkElement.) |
ComboBoxItem provides the container for items displayed in a ComboBox control. ComboBoxItem is a content control, which means to explicitly add content to a ComboBoxItem, you should set its Content property. However, typically a ComboBoxItem is created automatically for each item in a collection, bound to a ComboBox control.
You can use the ItemContainerGenerator to retrieve ComboBoxItem container objects by using an index or the item contained in the ComboBoxItem. For example, if you have a data-bound ComboBox and you want to get a ComboBoxItem based on its index, you can use the ContainerFromIndex method. If you want to retrieve the container based on the item, use the ContainerFromItem method.
 Note: |
|---|
If you populate a combo box with items that inherit from UIElement, the selected item can only appear in the visual tree one time. This means if an item is selected, it will appear in the selection box, and not in the drop-down list of items. When it is no longer the selected item, it will reappear in the drop-down list. If items do not inherit from UIElement they can appear in both the selection box and the drop-down list at the same time. |
You can determine whether a ComboBoxItem is a selected item by using the IsSelected property.
Customizing the ComboBoxItem Control
To apply the same property settings to multiple ComboBoxItem controls, use the Style property. To change the visual structure and visual behavior of a ComboBoxItem, copy and modify the default style and template of ComboBox control.
Dependency properties for this control might be set by the default style of the control. If a dependency property for a ComboBoxItem is set by its default style, the property might change from its default value when the ComboBoxItem appears in the application.
| Note: |
|---|
Setting a visual property will only have an effect if that property is both present in ComboBoxItem control's default template and is set by using a TemplateBinding. |
The following example shows how to add ComboBoxItem objects that contain a variety of content directly to a ComboBox control.
<StackPanel x:Name="LayoutRoot" Background="Transparent" > <TextBlock HorizontalAlignment="Center" Text="ComboBox Control" Margin="5"/> <ComboBox x:Name="myCombo" Width="150" Margin="10"> <ComboBoxItem Content="String Item" /> <ComboBoxItem> <ComboBoxItem.Content> <Button Content="Button Item" /> </ComboBoxItem.Content> </ComboBoxItem> <ComboBoxItem> <ComboBoxItem.Content> <StackPanel Orientation="Horizontal"> <Rectangle Height="10" Width="50" Fill="Blue" /> <TextBlock Margin="2" Text="Panel Item" /> </StackPanel> </ComboBoxItem.Content> </ComboBoxItem> </ComboBox> </StackPanel>
The following example shows how to retrieve a ComboBoxItem by using the ItemContainerGenerator of the associated ComboBox.
Public Sub New() InitializeComponent() Dim fonts As New System.Collections.ObjectModel.ObservableCollection(Of FontFamily)( {New FontFamily("Arial"), New FontFamily("Times New Roman"), New FontFamily("Courier New")}) CB.DataContext = fonts End Sub Private Sub Button_Click(ByVal sender As Object, ByVal e As RoutedEventArgs) Dim selectedItemContainer As ComboBoxItem = DirectCast(CB.ItemContainerGenerator.ContainerFromItem(CB.SelectedItem), ComboBoxItem) If selectedItemContainer IsNot Nothing Then selectedItemContainer.FontFamily = DirectCast(CB.SelectedItem, FontFamily) End If End Sub
<StackPanel x:Name="LayoutRoot" Background="Transparent"> <ComboBox x:Name="CB" Width="170" Height="30" ItemsSource="{Binding}" Margin="5"/> <Button Click="Button_Click" Width="170" Content="Change font of selected item" /> </StackPanel>
Show: