SwapChainPanel class

Applies to Windows and Windows Phone

Provides a hosting surface, where Microsoft DirectX swap chains provide content that can be rendered into a XAML UI. A SwapChainPanel element is a key component for an app that renders DirectX graphics and then presents those visuals within a XAML page.

Inheritance

Object
  DependencyObject
    UIElement
      FrameworkElement
        Panel
          Grid
            SwapChainPanel

Syntax


public ref class SwapChainPanel : Grid


<SwapChainPanel .../>

Attributes

[MarshalingBehavior(Agile)]
[Threading(Both)]
[Version(0x06030000)]
[WebHostHidden()]

Members

The SwapChainPanel class has these types of members:

Constructors

The SwapChainPanel class has these constructors.

ConstructorDescription
SwapChainPanel Initializes a new instance of the SwapChainPanel class.

 

Events

The SwapChainPanel class has these events.

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

 

Methods

The SwapChainPanel class has these methods. It also inherits methods from the Object class.

MethodDescription
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. (Inherited from 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. (Inherited from UIElement)
ArrangeOverride Provides the behavior for the Arrange pass of layout. Classes can override this method to define their own Arrange pass behavior. (Inherited from FrameworkElement)
CancelDirectManipulations Cancels ongoing direct manipulation processing (system-defined panning/zooming) on any ScrollViewer parent that contains the current UIElement. (Inherited from UIElement)
CapturePointer Sets pointer capture to a UIElement. Once captured, only the element that has capture will fire pointer-related events. (Inherited from UIElement)
ClearValue Clears the local value of a dependency property. (Inherited from DependencyObject)
CreateCoreIndependentInputSource Creates a core input object that handles the input types as specified by the deviceTypes parameter. This core input object can process input events on a background thread.
FindName Retrieves an object that has the specified identifier name. (Inherited from FrameworkElement)
FindSubElementsForTouchTargeting Enables a UIElement subclass to expose child elements that assist with resolving touch targeting. (Inherited from UIElement)
GetAnimationBaseValue Returns any base value established for a dependency property, which would apply in cases where an animation is not active. (Inherited from DependencyObject)
GetBindingExpression Returns the BindingExpression that represents the binding on the specified property. (Inherited from FrameworkElement)
GetValue Returns the current effective value of a dependency property from a DependencyObject. (Inherited from DependencyObject)
GoToElementStateCore When implemented in a derived class, enables per-state construction of a visual tree for a control template in code, rather than by loading XAML for all states at control startup. (Inherited from FrameworkElement)
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 the layout cycle. Classes can override this method to define their own Measure pass behavior. (Inherited from 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. (Inherited from FrameworkElement)
OnCreateAutomationPeer When implemented in a derived class, returns class-specific AutomationPeer implementations for the Microsoft UI Automation infrastructure. (Inherited from 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. (Inherited from UIElement)
ReadLocalValue Returns the local value of a dependency property, if a local value is set. (Inherited from DependencyObject)
ReleasePointerCapture Releases pointer captures for capture of one specific pointer by this UIElement. (Inherited from UIElement)
ReleasePointerCaptures Releases all pointer captures held by this element. (Inherited from UIElement)
RemoveHandler Removes the specified routed event handler from this UIElement. Typically the handler in question was added by AddHandler. (Inherited from UIElement)
SetBinding Attaches a binding to a FrameworkElement, using the provided binding object. (Inherited from FrameworkElement)
SetValue Sets the local value of a dependency property on a DependencyObject. (Inherited from DependencyObject)
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)

 

Properties

The SwapChainPanel class has these properties.

PropertyAccess typeDescription

ActualHeight

Read-onlyGets the rendered height of a FrameworkElement. (Inherited from FrameworkElement)

ActualWidth

Read-onlyGets the rendered width of a FrameworkElement. (Inherited from FrameworkElement)

AllowDrop

Read/writeGets 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

Read/writeGets or sets a Brush that is used to fill the panel. (Inherited from Panel)

BaseUri

Read-onlyGets 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. (Inherited from FrameworkElement)

CacheMode

Read/writeGets or sets a value that indicates that rendered content should be cached as a composited bitmap when possible. (Inherited from UIElement)

Children

Read-onlyGets the collection of child elements of the panel. (Inherited from Panel)

ChildrenTransitions

Read/writeGets or sets the collection of Transition style elements that apply to child content of a Panel subclass. (Inherited from Panel)

Clip

Read/writeGets or sets the RectangleGeometry used to define the outline of the contents of a UIElement. (Inherited from UIElement)

ColumnDefinitions

Read-onlyGets a list of ColumnDefinition objects defined on this instance of Grid. (Inherited from Grid)

CompositeMode

Read/writeGets or sets a property that declares alternate composition and blending modes for the element in its parent layout and window. This is relevant for elements that are involved in a mixed XAML / Microsoft DirectX UI. (Inherited from UIElement)

CompositionScaleX

Read-onlyGets the x-axis scale factor of the SwapChainPanel.

CompositionScaleXProperty

Read-onlyIdentifies the CompositionScaleX dependency property.

CompositionScaleY

Read-onlyGets the y-axis scale factor of the SwapChainPanel.

CompositionScaleYProperty

Read-onlyIdentifies the CompositionScaleY dependency property.

DataContext

Read/writeGets or sets the data context for a FrameworkElement when it participates in data binding. (Inherited from FrameworkElement)

DesiredSize

Read-onlyGets the size that this UIElement computed during the measure pass of the layout process. (Inherited from UIElement)

Dispatcher

Read-onlyGets the CoreDispatcher that this object is associated with. (Inherited from DependencyObject)

FlowDirection

Read/writeGets 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. (Inherited from FrameworkElement)

Height

Read/writeGets or sets the suggested height of a FrameworkElement. (Inherited from FrameworkElement)

HorizontalAlignment

Read/writeGets 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)

IsDoubleTapEnabled

Read/writeGets or sets a value that determines whether the DoubleTapped event can originate from that element. (Inherited from UIElement)

IsHitTestVisible

Read/writeGets or sets whether the contained area of this UIElement can return true values for hit testing. (Inherited from UIElement)

IsHoldingEnabled

Read/writeGets or sets a value that determines whether the Holding event can originate from that element. (Inherited from UIElement)

IsItemsHost

Read-onlyGets a value that indicates whether this Panel is a container for UI items that are generated by an ItemsControl. (Inherited from Panel)

IsRightTapEnabled

Read/writeGets or sets a value that determines whether the RightTapped event can originate from that element. (Inherited from UIElement)

IsTapEnabled

Read/writeGets or sets a value that determines whether the Tapped event can originate from that element. (Inherited from UIElement)

Language

Read/writeGets 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. (Inherited from FrameworkElement)

ManipulationMode

Read/writeGets or sets the ManipulationModes value used for UIElement behavior and interaction with gestures. Setting this value enables handling the manipulation events from this element in app code. (Inherited from UIElement)

Margin

Read/writeGets or sets the outer margin of a FrameworkElement. (Inherited from FrameworkElement)

MaxHeight

Read/writeGets or sets the maximum height constraint of a FrameworkElement. (Inherited from FrameworkElement)

MaxWidth

Read/writeGets or sets the maximum width constraint of a FrameworkElement. (Inherited from FrameworkElement)

MinHeight

Read/writeGets or sets the minimum height constraint of a FrameworkElement. (Inherited from FrameworkElement)

MinWidth

Read/writeGets or sets the minimum width constraint of a FrameworkElement. (Inherited from FrameworkElement)

Name

Read/writeGets 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

Read/writeGets or sets the degree of the object's opacity. (Inherited from UIElement)

Parent

Read-onlyGets the parent object of this FrameworkElement in the object tree. (Inherited from FrameworkElement)

PointerCaptures

Read-onlyGets the set of all captured pointers, represented as Pointer values. (Inherited from UIElement)

Projection

Read/writeGets or sets the perspective projection (3-D effect) to apply when rendering this element. (Inherited from UIElement)

RenderSize

Read-onlyGets the final render size of a UIElement. (Inherited from UIElement)

RenderTransform

Read/writeGets or sets transform information that affects the rendering position of a UIElement. (Inherited from UIElement)

RenderTransformOrigin

Read/writeGets or sets the origin point of any possible render transform declared by RenderTransform, relative to the bounds of the UIElement. (Inherited from UIElement)

RequestedTheme

Read/writeGets or sets the UI theme that is used by the UIElement (and its child elements) for resource determination. The UI theme you specify with RequestedTheme can override the app-level RequestedTheme. (Inherited from FrameworkElement)

Resources

Read/writeGets 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)

RowDefinitions

Read-onlyGets a list of RowDefinition objects defined on this instance of Grid. (Inherited from Grid)

Style

Read/writeGets or sets an instance Style that is applied for this object during layout and rendering. (Inherited from FrameworkElement)

Tag

Read/writeGets or sets an arbitrary object value that can be used to store custom information about this object. (Inherited from FrameworkElement)

Transitions

Read/writeGets or sets the collection of Transition style elements that apply to a UIElement. (Inherited from UIElement)

Triggers

Read-onlyGets the collection of triggers for animations that are defined for a FrameworkElement. Not commonly used. (Inherited from FrameworkElement)

UseLayoutRounding

Read/writeGets 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)

VerticalAlignment

Read/writeGets 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)

Visibility

Read/writeGets 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. (Inherited from UIElement)

Width

Read/writeGets or sets the width of a FrameworkElement. (Inherited from FrameworkElement)

 

Remarks

A SwapChainPanel is a Grid subclass, so you can use ColumnDefinitions and RowDefinitions properties to declare the panel's characteristics, and the attached properties of Grid such as Grid.Row and Grid.Column on child elements to position those child elements in the layout.

For code examples that use SwapChainPanel, see XAML SwapChainPanel DirectX interop sample. See also Prepare your development environment for DirectX Windows Store apps.

The SwapChainPanel class does not inherit from the Control class, so you can't programmatically focus it directly for purposes of capturing key events. Consider setting the focus to a focusable element inside the panel and letting the key event bubble.

In order to maintain crisp vector rendering, you should listen for the CompositionScaleChanged event and query the CompositionScaleX and CompositionScaleY property values to account for the current UI scale, and potentially render again from DirectX. Otherwise XAML layout might do the scaling and your visuals might be degraded.

Initializing a SwapChainPanel element

Before a SwapChainPanel can render content, you must initialize it from the DirectX side.

Cast the SwapChainPanel instance to IInspectable or IUnknown, then call QueryInterface to obtain a reference to the ISwapChainPanelNative interface (this is the native interface implementation that is the complement to the SwapChainPanel and enables the interop bridge). Then, call ISwapChainPanelNative::SetSwapChain on that reference to associate your implemented swap chain with the SwapChainPanel instance.

It's common to put the code that queries the interface and sets the swap chain as part of a Create*Resources method. The Create*Resources methods are an implementation pattern that's seen in the DirectX Renderer class templates/examples, and you'll also see this implementation pattern in the SDK samples, and in the code you get from the DirectX (XAML) project template in Microsoft Visual Studio. Specifically, in the DirectX (XAML) project template, you'll see the QueryInterface call and the call to ISwapChainPanelNative::SetSwapChain in the DeviceResources::CreateWindowSizeDependentResources method implementation in DeviceResources.cpp.

The API that enables you to add a SwapChain to an existing SwapChainPanel is not a runtime class API, it is a DirectX API. You implement the swap chain input as a DirectX interface (IDXGISwapChain).

SwapChainPanel and SwapChainBackgroundPanel

SwapChainPanel has less restrictions on its interactions and placement in UI than does SwapChainBackgroundPanel.

  • SwapChainPanel can be used as a control anywhere in a visual tree of a page. SwapChainBackgroundPanel can only be the root element.
  • The typical XAML UI APIs that are inherited from the Grid base class can be used on a SwapChainPanel. SwapChainBackgroundPanel doesn't permit you to set most Grid inherited APIs.
  • For new apps you should generally use SwapChainPanel and should consider SwapChainBackgroundPanel to be a legacy technique for Windows 8 apps that weren't updated for Windows 8.1.

Swap chains

  • Swap chains must run on the main UI thread. This is usually accomplished by calling SetSwapChain on a reference that was initialized as a XAML object element.
  • A single swap chain can be associated with multiple SwapChainPanel elements. Or, your app can have multiple swap chains, with each providing the presentation for a separate SwapChainPanel.
  • However, performance can decline if many swap chains are updated simultaneously. We recommend that your app use no more than four swap chains.
  • Content that's rendered via the swap chain is not stretched when it's resized by the user; instead, the resizing behavior is similar to setting Stretch="None" on an Image element.
  • There are other techniques for rendering swap chain content that goes directly to the app's core window rather than a XAML-composed element. See CreateSwapChainForCoreWindow.

Processing input on background threads

Using the CreateCoreIndependentInputSource method, apps can process input and render to a SwapChainPanel entirely on one or more background threads. This enables high performance input and rendering independent of the XAML UI thread.

Requirements

Minimum supported client

Windows 8.1 [Windows Store apps only]

Minimum supported server

Windows Server 2012 R2 [Windows Store apps only]

Minimum supported phone

Windows Phone 8.1 [Windows Runtime apps only]

Namespace

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

Metadata

Windows.winmd

See also

Grid
SwapChainBackgroundPanel
ISwapChainPanelNative
DirectX and XAML interop
XAML SwapChainPanel DirectX interop sample
Prepare your development environment for DirectX Windows Store apps

 

 

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