Image class
Represents a control that displays an image. The image is specified as an image file in several possible formats. See Remarks.
Inheritance
Syntax
<Image .../>
Attributes
- ActivatableAttribute(NTDDI_WIN8)
- MarshalingBehaviorAttribute(Agile)
- StaticAttribute(Windows.UI.Xaml.Controls.IImageStatics, NTDDI_WIN8)
- ThreadingAttribute(Both)
- VersionAttribute(NTDDI_WIN8)
- WebHostHiddenAttribute()
Members
The Image class has these types of members:
Constructors
The Image class has these constructors.
| Constructor | Description |
|---|---|
| Image | Initializes a new instance of the Image class. |
Events
The Image class has these events.
| Event | Description |
|---|---|
| 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) |
| ImageFailed | Occurs when there is an error associated with image retrieval or format. |
| ImageOpened | Occurs when the image source is downloaded and decoded with no failure. You can use this event to determine the size of an image before rendering it. |
| 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. (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 Image class has these methods. It also inherits methods from the Object class.
| Method | 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 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) |
| 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) |
| 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) |
| 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 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 Image class has these properties.
| Property | Access type | Description |
|---|---|---|
| Read-only | Gets the rendered height of a FrameworkElement. (Inherited from FrameworkElement) | |
| Read-only | Gets the rendered width of a FrameworkElement. (Inherited from FrameworkElement) | |
| Read/write | 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) | |
| Read-only | Gets 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) | |
| Read/write | Gets or sets a value that indicates that rendered content should be cached as a composited bitmap when possible. (Inherited from UIElement) | |
| Read/write | Gets or sets the RectangleGeometry used to define the outline of the contents of a UIElement. (Inherited from UIElement) | |
| Read/write | Gets or sets the data context for a FrameworkElement when it participates in data binding. (Inherited from FrameworkElement) | |
| Read-only | Gets the size that this UIElement computed during the measure pass of the layout process. (Inherited from UIElement) | |
| Read-only | Gets the CoreDispatcher that this object is associated with. (Inherited from DependencyObject) | |
| Read/write | Gets 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) | |
| Read/write | Gets or sets the suggested height of a FrameworkElement. (Inherited from FrameworkElement) | |
| Read/write | 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) | |
| Read/write | Gets or sets a value that determines whether the DoubleTapped event can originate from that element. (Inherited from UIElement) | |
| Read/write | Gets or sets whether the contained area of this UIElement can return true values for hit testing. (Inherited from UIElement) | |
| Read/write | Gets or sets a value that determines whether the Holding event can originate from that element. (Inherited from UIElement) | |
| Read/write | Gets or sets a value that determines whether the RightTapped event can originate from that element. (Inherited from UIElement) | |
| Read/write | Gets or sets a value that determines whether the Tapped event can originate from that element. (Inherited from UIElement) | |
| Read/write | Gets 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) | |
| Read/write | Gets or sets the ManipulationModes value used for UIElement behavior and interaction with gestures. (Inherited from UIElement) | |
| Read/write | Gets or sets the outer margin of a FrameworkElement. (Inherited from FrameworkElement) | |
| Read/write | Gets or sets the maximum height constraint of a FrameworkElement. (Inherited from FrameworkElement) | |
| Read/write | Gets or sets the maximum width constraint of a FrameworkElement. (Inherited from FrameworkElement) | |
| Read/write | Gets or sets the minimum height constraint of a FrameworkElement. (Inherited from FrameworkElement) | |
| Read/write | Gets or sets the minimum width constraint of a FrameworkElement. (Inherited from FrameworkElement) | |
| Read/write | 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) | |
| Read/write | Gets or sets a value for a nine-grid metaphor that controls how the image can be resized. | |
| Read-only | Identifies the NineGrid dependency property. | |
| Read/write | Gets or sets the degree of the object's opacity. (Inherited from UIElement) | |
| Read-only | Gets the parent object of this FrameworkElement in the object tree. (Inherited from FrameworkElement) | |
| Read-only | Gets the information that is transmitted if the Image is used for a "PlayTo" scenario. | |
| Read-only | Identifies the PlayToSource dependency property. | |
| Read-only | Gets the set of all captured pointers, represented as Pointer values. (Inherited from UIElement) | |
| Read/write | Gets or sets the perspective projection (3-D effect) to apply when rendering this element. (Inherited from UIElement) | |
| Read-only | Gets the final render size of a UIElement. (Inherited from UIElement) | |
| Read/write | Gets or sets transform information that affects the rendering position of a UIElement. (Inherited from UIElement) | |
| Read/write | Gets or sets the origin point of any possible render transform declared by RenderTransform, relative to the bounds of the UIElement. (Inherited from UIElement) | |
| Read/write | 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) | |
| Read/write | Gets or sets the source for the image. | |
| Read-only | Identifies the Source dependency property. | |
| Read/write | Gets or sets a value that describes how an Image should be stretched to fill the destination rectangle. | |
| Read-only | Identifies the Stretch dependency property. | |
| Read/write | Gets or sets an instance Style that is applied for this object during layout and rendering. (Inherited from FrameworkElement) | |
| Read/write | Gets or sets an arbitrary object value that can be used to store custom information about this object. (Inherited from FrameworkElement) | |
| Read/write | Gets or sets the collection of Transition style elements that apply to a UIElement. (Inherited from UIElement) | |
| Read-only | Gets the collection of triggers for animations that are defined for a FrameworkElement. Not commonly used. (Inherited from FrameworkElement) | |
| Read/write | 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) | |
| Read/write | 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) | |
| Read/write | Gets 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) | |
| Read/write | Gets or sets the width of a FrameworkElement. (Inherited from FrameworkElement) |
Remarks
To set the image source file that an Image displays, you set its Source property. For more info, see Remarks in Source.
Setting the Source is inherently an asynchronous action. Setting the source to a Uniform Resource Identifier (URI) value that cannot be resolved to a valid image source file does not throw an exception. Instead, it fires an ImageFailed event on the Image itself. You can write an ImageFailed handler and attach it to the Image to detect this case, and possibly use the ErrorMessage in event data to determine the nature of the failure. If you want to verify that an image source file did load correctly, you can handle ImageOpened.
Image is not a true control in that it is not a descendant class of Control. You can't call focus to an Image or put it in a tab sequence.
If you define an Image using code, use the default constructor, then set Image.Source. This requires a BitmapImage (not a URI) in code. If your source is a stream, use the SetSourceAsync method to initialize the value. If your source is a URI, which includes content in your app that uses the ms-appx or ms-resource schemes, use the BitmapImage constructor that takes a URI. You might also consider handling the ImageOpened event if there are any timing issues with retrieving or decoding the image source, where you might need alternate content to display until the image source is available. See XAML images sample for example code.
Note You can use automatic handling for accessing unqualified resources with current scale and culture qualifiers, or you can use ResourceManager and ResourceMap with qualifiers for culture and scale to obtain the resources directly. For more info see Resource management system.
Image file formats
An Image can display these image file formats:
- Joint Photographic Experts Group (JPEG)
- Portable Network Graphics (PNG)
- bitmap (BMP)
- Graphics Interchange Format (GIF)
- Tagged Image File Format (TIFF)
- JPEG XR
- icons (ICO)
The underlying codec support for image files is supplied by Windows Imaging Component (WIC) API in Windows 8. For more info on specific image formats as documented for the codecs, see Native WIC Codecs.
The API for Image, BitmapImage and BitmapSource doesn't include any dedicated methods for encoding and decoding of media formats. All of the encode and decode operations are built-in, and at most will surface aspects of encode or decode as part of event data for load events. If you want to do any special work with image encode or decode, which you might use if your app is doing image conversions or manipulation, you should use the APIs that are available in the Windows.Graphics.Imaging namespace. These imaging APIs can be used by either Windows Store apps built for Windows using C++, C#, or Visual Basic or Windows Store apps using JavaScript. These APIs are also supported by the WIC component of Windows 8.
For more info on app resources and how to package image sources in an app, see Defining app resources.
Image sources and scaling
You should create your image sources at several recommended sizes, to ensure that your app looks great when Windows 8 scales it. When specifying a Source for an Image, you can use a naming convention that will automatically reference the correct resource for the current scaling. For specifics of the naming convention and more info, see Quickstart: Using file or image resources.
For more info on how to design for scaling, see Guidelines for scaling to pixel density.
FlowDirection for Image
if you set FlowDirection as RightToLeft for an Image, the visual content of an Image is flipped horizontally. However, an Image element does not inherit the FlowDirection value from any parent element. Typically you only want image-flipping behavior in images that are relevant to layout, but not necessarily to elements that have embedded text or other components that wouldn't make sense flipped for a right-to-left audience. To get image-flip behavior, you must set the FlowDirection element on the Image element specifically to RightToLeft, or set the FlowDirection property in code-behind. Consider identifying the Image element by x:Uid, and specifying FlowDirection values as a RESW resource, so that your localization experts can change this value later without changing the XAML or code.
Requirements
|
Minimum supported client | Windows 8 [Windows Store apps only] |
|---|---|
|
Minimum supported server | Windows Server 2012 [Windows Store apps only] |
|
Namespace |
|
|
Metadata |
|
See also
- FrameworkElement
- Quickstart: Image and ImageBrush
- XAML images sample
- BitmapSource
- FlowDirection
- Windows.Graphics.Imaging
Build date: 3/12/2013
