Windows Dev Center

CaptureElement Class

Esegue il rendering di un flusso da un dispositivo di acquisizione, ad esempio una fotocamera o una webcam.

Ereditarietà

Object
  DependencyObject
    UIElement
      FrameworkElement
        CaptureElement

Sintassi


public sealed class CaptureElement : FrameworkElement

Attributi

ActivatableAttribute(NTDDI_WIN8)
MarshalingBehaviorAttribute(Agile)
StaticAttribute(Windows.UI.Xaml.Controls.ICaptureElementStatics, NTDDI_WIN8)
ThreadingAttribute(Both)
VersionAttribute(NTDDI_WIN8)
WebHostHiddenAttribute()

Membri

Il CaptureElementClasse dispone di questi tipi di membri:

Costruttori

Il CaptureElementClasse dispone di questi costruttori.

CostruttoreDescrizione
CaptureElement Initializes a new instance of the CaptureElement class.

 

Eventi

Il CaptureElementClasse dispone di questi eventi.

EventoDescrizione
DoubleTapped Occurs when an otherwise unhandled DoubleTap interaction occurs over the hit test area of this element. (Ereditato da UIElement)
DragEnter Occurs when the input system reports an underlying drag event with this element as the target. (Ereditato da UIElement)
DragLeave Occurs when the input system reports an underlying drag event with this element as the origin. (Ereditato da UIElement)
DragOver Occurs when the input system reports an underlying drag event with this element as the potential drop target. (Ereditato da UIElement)
Drop Occurs when the input system reports an underlying drop event with this element as the drop target. (Ereditato da UIElement)
GotFocus Occurs when a UIElement receives focus. (Ereditato da UIElement)
Holding Occurs when an otherwise unhandled Hold interaction occurs over the hit test area of this element. (Ereditato da UIElement)
KeyDown Occurs when a keyboard key is pressed while the UIElement has focus. (Ereditato da UIElement)
KeyUp Occurs when a keyboard key is released while the UIElement has focus. (Ereditato da UIElement)
LayoutUpdated Occurs when the layout of the visual tree changes. (Ereditato da FrameworkElement)
Loaded Occurs when a FrameworkElement has been constructed and added to the object tree, and is ready for interaction. (Ereditato da FrameworkElement)
LostFocus Occurs when a UIElement loses focus. (Ereditato da UIElement)
ManipulationCompleted Occurs when a manipulation on the UIElement is complete. (Ereditato da UIElement)
ManipulationDelta Occurs when the input device changes position during a manipulation. (Ereditato da UIElement)
ManipulationInertiaStarting Occurs when the input device loses contact with the UIElement object during a manipulation and inertia begins. (Ereditato da UIElement)
ManipulationStarted Occurs when an input device begins a manipulation on the UIElement. (Ereditato da UIElement)
ManipulationStarting Occurs when the manipulation processor is first created. (Ereditato da UIElement)
PointerCanceled Occurs when a pointer that made contact abnormally loses contact. (Ereditato da UIElement)
PointerCaptureLost Occurs when pointer capture previously held by this element moves to another element or elsewhere. (Ereditato da UIElement)
PointerEntered Occurs when a pointer enters the hit test area of this element. (Ereditato da UIElement)
PointerExited Occurs when a pointer leaves the hit test area of this element. (Ereditato da UIElement)
PointerMoved Occurs when a pointer moves while the pointer remains within the hit test area of this element. (Ereditato da UIElement)
PointerPressed Occurs when the pointer device initiates a Press action within this element. (Ereditato da UIElement)
PointerReleased Occurs when the pointer device that previously initiated a Press action is released, while within this element. (Ereditato da UIElement)
PointerWheelChanged Occurs when the delta value of a pointer wheel changes. (Ereditato da UIElement)
RightTapped Occurs when a right-tap input stimulus happens while the pointer is over the element. (Ereditato da UIElement)
SizeChanged Occurs when either the ActualHeight or the ActualWidth property changes value on a FrameworkElement. (Ereditato da FrameworkElement)
Tapped Occurs when an otherwise unhandled Tap interaction occurs over the hit test area of this element. (Ereditato da UIElement)
Unloaded Occurs when this object is no longer connected to the main object tree. (Ereditato da FrameworkElement)

 

Metodi

The CaptureElement Classe dispone di questi metodi. Eredita inoltre i metodi da Object Classe.

MetodoDescrizione
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 even if the event is handled elsewhere. (Ereditato da UIElement)
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. (Ereditato da UIElement)
ArrangeOverride Provides the behavior for the Arrange pass of layout. Classes can override this method to define their own Arrange pass behavior. (Ereditato da FrameworkElement)
CapturePointer Sets pointer capture to a UIElement. Once captured, only the element that has capture will fire pointer-related events. (Ereditato da UIElement)
ClearValue Clears the local value of a dependency property. (Ereditato da DependencyObject)
FindName Retrieves an object that has the specified identifier name. (Ereditato da FrameworkElement)
FindSubElementsForTouchTargeting Enables a UIElement subclass to expose child elements that assist with resolving touch targeting. (Ereditato da UIElement)
GetAnimationBaseValue Returns any base value established for a dependency property, which would apply in cases where an animation is not active. (Ereditato da DependencyObject)
GetValue Returns the current effective value of a dependency property from a DependencyObject. (Ereditato da DependencyObject)
InvalidateArrange Invalidates the arrange state (layout) for a UIElement. After the invalidation, the UIElement will have its layout updated, which will occur asynchronously. (Ereditato da UIElement)
InvalidateMeasure Invalidates the measurement state (layout) for a UIElement. (Ereditato da 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. (Ereditato da UIElement)
MeasureOverride Provides the behavior for the Measure pass of the layout cycle. Classes can override this method to define their own Measure pass behavior. (Ereditato da FrameworkElement)
OnApplyTemplate Invoked whenever application code or internal processes (such as a rebuilding layout pass) call ApplyTemplate. In simplest terms, this means the method is called just before a UI element displays in your app. Override this method to influence the default post-template logic of a class. (Ereditato da FrameworkElement)
OnCreateAutomationPeer When implemented in a derived class, returns class-specific AutomationPeer implementations for the Microsoft UI Automation infrastructure. (Ereditato da UIElement)
OnDisconnectVisualChildren Override this method to implement how layout and logic should behave when items are removed from a class-specific content or children property. (Ereditato da UIElement)
ReadLocalValue Returns the local value of a dependency property, if a local value is set. (Ereditato da DependencyObject)
ReleasePointerCapture Releases pointer captures for capture of one specific pointer by this UIElement. (Ereditato da UIElement)
ReleasePointerCaptures Releases all pointer captures held by this element. (Ereditato da UIElement)
RemoveHandler Removes the specified routed event handler from this UIElement. Typically the handler in question was added by AddHandler. (Ereditato da UIElement)
SetBinding Attaches a binding to a FrameworkElement, using the provided binding object. (Ereditato da FrameworkElement)
SetValue Sets the local value of a dependency property on a DependencyObject. (Ereditato da DependencyObject)
TransformToVisual Returns a transform object that can be used to transform coordinates from the UIElement to the specified object. (Ereditato da UIElement)
UpdateLayout Ensures that all positions of child objects of a UIElement are properly updated for layout. (Ereditato da UIElement)

 

Proprietà

CaptureElementClasse dispone di queste proprietà.

ProprietàTipo accessoDescrizione

ActualHeight

Sola letturaGets the rendered height of a FrameworkElement. (Ereditato da FrameworkElement)

ActualWidth

Sola letturaGets the rendered width of a FrameworkElement. (Ereditato da FrameworkElement)

AllowDrop

Lettura/scritturaGets or sets a value that determines whether this UIElement can be a drop target for purposes of drag-and-drop operations. (Ereditato da UIElement)

BaseUri

Sola letturaGets a Uniform Resource Identifier (URI) that represents the base Uniform Resource Identifier (URI) for an XAML-constructed object at XAML load time. This property is useful for Uniform Resource Identifier (URI) resolution at run time. (Ereditato da FrameworkElement)

CacheMode

Lettura/scritturaGets or sets a value that indicates that rendered content should be cached as a composited bitmap when possible. (Ereditato da UIElement)

Clip

Lettura/scritturaGets or sets the RectangleGeometry used to define the outline of the contents of a UIElement. (Ereditato da UIElement)

DataContext

Lettura/scritturaGets or sets the data context for a FrameworkElement when it participates in data binding. (Ereditato da FrameworkElement)

DesiredSize

Sola letturaGets the size that this UIElement computed during the measure pass of the layout process. (Ereditato da UIElement)

Dispatcher

Sola letturaGets the CoreDispatcher that this object is associated with. (Ereditato da DependencyObject)

FlowDirection

Lettura/scritturaGets or sets the direction in which text and other UI elements flow within any parent element that controls their layout. This property can be set to either LeftToRight or RightToLeft. Setting FlowDirection to RightToLeft on any element sets the alignment to the right, the reading order to right-to-left and the layout of the control to flow from right to left. (Ereditato da FrameworkElement)

Height

Lettura/scritturaGets or sets the suggested height of a FrameworkElement. (Ereditato da FrameworkElement)

HorizontalAlignment

Lettura/scritturaGets 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. (Ereditato da FrameworkElement)

IsDoubleTapEnabled

Lettura/scritturaGets or sets a value that determines whether the DoubleTapped event can originate from that element. (Ereditato da UIElement)

IsHitTestVisible

Lettura/scritturaGets or sets whether the contained area of this UIElement can return true values for hit testing. (Ereditato da UIElement)

IsHoldingEnabled

Lettura/scritturaGets or sets a value that determines whether the Holding event can originate from that element. (Ereditato da UIElement)

IsRightTapEnabled

Lettura/scritturaGets or sets a value that determines whether the RightTapped event can originate from that element. (Ereditato da UIElement)

IsTapEnabled

Lettura/scritturaGets or sets a value that determines whether the Tapped event can originate from that element. (Ereditato da UIElement)

Language

Lettura/scritturaGets or sets localization/globalization language information that applies to a FrameworkElement, and also to all child elements of the current FrameworkElement in the object representation and in UI. (Ereditato da FrameworkElement)

ManipulationMode

Lettura/scritturaGets or sets the ManipulationModes value used for UIElement behavior and interaction with gestures. (Ereditato da UIElement)

Margin

Lettura/scritturaGets or sets the outer margin of a FrameworkElement. (Ereditato da FrameworkElement)

MaxHeight

Lettura/scritturaGets or sets the maximum height constraint of a FrameworkElement. (Ereditato da FrameworkElement)

MaxWidth

Lettura/scritturaGets or sets the maximum width constraint of a FrameworkElement. (Ereditato da FrameworkElement)

MinHeight

Lettura/scritturaGets or sets the minimum height constraint of a FrameworkElement. (Ereditato da FrameworkElement)

MinWidth

Lettura/scritturaGets or sets the minimum width constraint of a FrameworkElement. (Ereditato da FrameworkElement)

Name

Lettura/scritturaGets 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. (Ereditato da FrameworkElement)

Opacity

Lettura/scritturaGets or sets the degree of the object's opacity. (Ereditato da UIElement)

Parent

Sola letturaGets the parent object of this FrameworkElement in the object tree. (Ereditato da FrameworkElement)

PointerCaptures

Sola letturaGets the set of all captured pointers, represented as Pointer values. (Ereditato da UIElement)

Projection

Lettura/scritturaGets or sets the perspective projection (3-D effect) to apply when rendering this element. (Ereditato da UIElement)

RenderSize

Sola letturaGets the final render size of a UIElement. (Ereditato da UIElement)

RenderTransform

Lettura/scritturaGets or sets transform information that affects the rendering position of a UIElement. (Ereditato da UIElement)

RenderTransformOrigin

Lettura/scritturaGets or sets the origin point of any possible render transform declared by RenderTransform, relative to the bounds of the UIElement. (Ereditato da UIElement)

Resources

Lettura/scritturaGets 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. (Ereditato da FrameworkElement)

Source

Lettura/scritturaGets or sets the source MediaCapture that this CaptureElement represents.

SourceProperty

Sola letturaIdentifies the Source dependency property.

Stretch

Lettura/scritturaGets or sets how content from Source is resized to fill its allocated space, as declared by the Height and Width properties of the CaptureElement.

StretchProperty

Sola letturaIdentifies the Stretch dependency property.

Style

Lettura/scritturaGets or sets an instance Style that is applied for this object during layout and rendering. (Ereditato da FrameworkElement)

Tag

Lettura/scritturaGets or sets an arbitrary object value that can be used to store custom information about this object. (Ereditato da FrameworkElement)

Transitions

Lettura/scritturaGets or sets the collection of Transition style elements that apply to a UIElement. (Ereditato da UIElement)

Triggers

Sola letturaGets the collection of triggers for animations that are defined for a FrameworkElement. Not commonly used. (Ereditato da FrameworkElement)

UseLayoutRounding

Lettura/scritturaGets 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. (Ereditato da UIElement)

VerticalAlignment

Lettura/scritturaGets 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. (Ereditato da FrameworkElement)

Visibility

Lettura/scritturaGets or sets the visibility of a UIElement. A UIElement that is not visible is not rendered and does not communicate its desired size to layout. (Ereditato da UIElement)

Width

Lettura/scritturaGets or sets the width of a FrameworkElement. (Ereditato da FrameworkElement)

 

Osservazioni

La classe CaptureElement è utilizzata in combinazione con l'API di Windows.Media.Capture.MediaCapture. Utilizzare l'oggetto MediaCapture per controllare il flusso e impostare le opzioni nel dispositivo di acquisizione.

CaptureElement è la parte dell'interfaccia utente del flusso associato a MediaCapture.

È possibile utilizzare al massimo un CaptureElement per eseguire un flusso da un singolo dispositivo di acquisizione.

Esempi

L'esempio seguente mostra come creare un CaptureElement in XAML e come associarlo a un oggetto MediaCapture a livello di codice.


<CaptureElement x:Name="myCaptureElement" 
                HorizontalAlignment="Left"         
                Width="320" Height="240" />


async void ShowPreview(object sender, RoutedEventArgs e)
{           
    if (mediaCaptureMgr == null)
    {              
        // Using Windows.Media.Capture.MediaCapture APIs 
        // to stream from webcam
        mediaCaptureMgr = new MediaCapture();
        await mediaCaptureMgr.InitializeAsync();

        myCaptureElement.Source = mediaCaptureMgr;
        await mediaCaptureMgr.StartPreviewAsync();
    }
}


Requisiti

Client minimo supportato

Windows 8 [solo app di Windows Store]

Server minimo supportato

Windows Server 2012 [solo app di Windows Store]

Spazio dei nomi

Windows.UI.Xaml.Controls
Windows::UI::Xaml::Controls [C++]

Metadati

Windows.winmd

Vedi anche

FrameworkElement

 

 

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