Xamarin.Forms Namespace

Reference

Important

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Cross-platform, natively-backed UI toolkit.

Classes

AbsoluteLayout	Positions child elements at absolute positions.
Accelerator	Represents a shortcut key for a MenuItem.
AcceleratorTypeConverter	Class that the XAML parser uses to convert strings to Accelerator objects.
ActivityIndicator	A visual control used to indicate that something is ongoing.
AdaptiveTrigger
Animation	Encapsulates an animation, a collection of functions that modify properties over a user-perceptible time period.
AnimationExtensions	Extension methods for IAnimatable objects.
Application	Class that represents a cross-platform mobile application.
AppLinkEntry	A deep application link in an app link search index.
AppThemeChangedEventArgs
AutomationProperties	Contains both abbreviated and detailed UI information that is supplied to accessibility services.
BackButtonBehavior	A BindableObject specifying the behavior associated with the back button in a Shell application.
BackButtonPressedEventArgs	Internal use only. Contains arguments for the event that is raised when a back button is pressed.
BaseMenuItem	Base class for menu items.
BaseShellItem	A NavigableElement that is the base class for ShellGroupItem and ShellContent.
BaseSwipeEventArgs
Behavior	Base class for generalized user-defined behaviors that can respond to arbitrary conditions and events.
Behavior<T>	Base generic class for generalized user-defined behaviors that can respond to arbitrary conditions and events.
BindableLayout	Static class specifying the attached properties that allow a Layout<T> work with a data-bound System.Collections.IEnumerable.
BindableObject	Provides a mechanism by which application developers can propagate changes that are made to data in one object to another, by enabling validation, type coercion, and an event system. BindableProperty.
BindableObjectExtensions	Contains convenience extension methods for BindableObject.
BindableProperty	A BindableProperty is a backing store for properties allowing bindings on BindableObject.
BindablePropertyConverter	A TypeConverter for bindable properties.
BindablePropertyKey	The secret key to a BindableProperty, used to implement a BindableProperty with restricted write access.
Binding	A single 1:1 immutable data binding.
BindingBase	An abstract class that provides a BindingMode and a formatting option.
BindingCondition	Class that represents a value comparison with the target of an arbitrary binding.
BindingTypeConverter	Type converter that converts from strings to Binding objects.
BoundsConstraint	A bounds layout constraint used by RelativeLayouts.
BoundsTypeConverter	A TypeConverter that converts strings into Rectangles for use with AbsoluteLayouts.
BoxView	A View used to draw a solid colored rectangle.
Brush
BrushTypeConverter
BrushTypeConverter.GradientBrushParser
Button	A button View that reacts to touch events.
Button.ButtonContentLayout	Controls the relative positioning of, and spacing between, text and an image on a Button.
Button.ButtonContentTypeConverter	Class that the XAML parser uses to convert strings to Button.ButtonContentLayout objects.
CarouselLayoutTypeConverter
CarouselPage	A Page that users can swipe from side to side to display pages of content, like a gallery.
CarouselView	A ItemsView whose scrollable child views 'snap' into place.
Cell	Provides base class and capabilities for all Xamarin.Forms cells. Cells are elements meant to be added to ListView or TableView.
CheckBox
CheckedChangedEventArgs	Event Args for CheckBox's CheckedChanged event.
ChildGestureRecognizer	A gesture recognizer for use as a child of another.
ClickedEventArgs	Event arguments for a click event.
ClickGestureRecognizer	Recognizer for click gestures.
CollectionView	A SelectableItemsView that presents a collection of items.
ColorTypeConverter	A TypeConverter that converts from strings to a Color.
ColumnDefinition	An IDefinition that defines properties for a column in a Grid.
ColumnDefinitionCollection	A DefinitionCollection<T> for ColumnDefinitions.
ColumnDefinitionCollectionTypeConverter
Command	Defines an System.Windows.Input.ICommand implementation that wraps a System.Action.
Command<T>	Defines an System.Windows.Input.ICommand implementation wrapping a generic Action<T>.
CompareStateTrigger
CompressedLayout	Contains attached properties for omitting redundant renderers.
Condition	Base class for conditions.
Configuration<TPlatform,TElement>	Utility class for retrieving platform-specific versions of elements.
Constraint	A layout constraint used by RelativeLayouts.
ConstraintExpression	Defines a constraint relationship.
ConstraintTypeConverter	A TypeConverter that converts from strings to a Constraint.
ContentPage	A Page that displays a single view.
ContentPresenter	Layout manager for templated views.
ContentPropertyAttribute	Indicates the property of the type that is the (default) content property.
ContentView	An element that contains a single child element.
ControlTemplate	Template that specifies a group of styles and effects for controls.
CornerRadiusTypeConverter	A TypeConverter subclass that can convert a string to a CornerRadius.
CurrentItemChangedEventArgs
DataPackage
DataPackagePropertySet
DataPackagePropertySetView
DataPackageView
DataTemplate	A template for multiple bindings, commonly used by ListViews and MultiPage<T>s.
DataTemplateSelector	Selects DataTemplate objects by data type and container.
DataTrigger	Class that represents a condition on an arbitrary binding, along with a list of Setter objects that will be applied when the condition is met.
DateChangedEventArgs	Event arguments for DateSelected event.
DatePicker	A View that allows date picking.
DefinitionCollection<T>	A collection parameterized by an IDefinition. Base class for ColumnDefinitionCollection and RowDefinitionCollection.
DependencyAttribute	An attribute that indicates that the specified type provides a concrete implementation of a needed interface.
DependencyService	Static class that provides the Get<T>(DependencyFetchTarget) factory method for retrieving platform-specific implementations of the specified type T.
DesignMode	Static class that developers can use to determine if the application is running in a previewer.
Device	A utility class to interact with the current Device/Platform.
Device.Styles	Class that exposes device-specific styles as static fields.
DeviceStateTrigger
DoubleCollection
DoubleCollectionConverter
DragEventArgs
DragGestureRecognizer
DragStartingEventArgs
DropCompletedEventArgs
DropEventArgs
DropGestureRecognizer
Easing	Functions that modify values non-linearly, generally used for animations.
EasingTypeConverter
Editor	A control that can edit multiple lines of text.
Effect	A collection of styles and properties that can be added to an element at run time.
EffectiveFlowDirectionExtensions	Extension methods for finding out the flow direction and whether it was explicitly set.
EffectiveVisualExtensions
Element	Provides the base class for all Xamarin.Forms hierarchal elements. This class contains all the methods and properties required to represent an element in the Xamarin.Forms hierarchy.
ElementEventArgs	Provides data for events pertaining to a single Element.
ElementTemplate	Base class for DataTemplate and ControlTemplate classes.
EmbeddedFont
Entry	A control that can edit a single line of text.
EntryCell	A Cell with a label and a single line text entry field.
EventTrigger	Class that represents a triggering event and a list of TriggerAction objects that will be invoked when the event is raised.
ExportEffectAttribute	Attribute that identifies a Effect with a unique identifier that can be used with Resolve(String) to locate an effect.
ExportFontAttribute
FileImageSource	An ImageSource that reads an image from a file.
FileImageSourceConverter	A TypeConverter that converts to FileImageSource.
FlexAlignContentTypeConverter	Converts a string representation of a child content row alignment style to a FlexAlignContent.
FlexAlignItemsTypeConverter	Converts a string representation of a child content alignment style to a FlexAlignItems.
FlexAlignSelfTypeConverter	Converts a string representation of an alignment override to a FlexAlignSelf.
FlexBasis.FlexBasisTypeConverter	Converts a string representation of a flex basis to a FlexBasis.
FlexDirectionTypeConverter	Converts a string representation of a row or column flex layout direction to a FlexDirection.
FlexJustifyTypeConverter	Converts a string representation of a child element justification style to a FlexJustify.
FlexLayout	A Flexbox-like layout that lays out child elements in optionally wrappable rows or columns of child elements.
FlexWrapTypeConverter	Converts a string representation of a wrapping style to a FlexWrap.
FlowDirectionConverter	Converts a string representation of a flow direction to a FlowDirection.
FlyoutItem	A ShellItem that has a collection of Tab objects.
FlyoutPage
FocusEventArgs	Event args for VisualElement's Focused and Unfocused events.
FontAttributesConverter	Converts a string into a FontAttributes object.
FontFile
FontImageSource
FontSizeConverter	Converts a string into a font size.
FontTypeConverter	A TypeConverter that converts from strings to Font.
FormattedString	Represents a text with attributes applied to some parts.
Frame	An element containing a single child, with some framing options.
GestureElement	An element that can respond to gestures.
GestureRecognizer	The base class for all gesture recognizers.
GradientBrush
GradientStop
GradientStopCollection
Grid	A layout that arranges views in rows and columns.
GridItemsLayout
GridLengthTypeConverter	A TypeConverter that converts from strings to GridLengths.
GroupableItemsView
HandlerAttribute	An abstract attribute whose subclasses specify the platform-specific renderers for Xamarin.Forms abstract controls.
HtmlWebViewSource	A WebViewSource bound to an HTML-formatted string.
Image	View that holds an image.
ImageButton
ImageCell	A TextCell that has an image.
ImageSource	Abstract class whose implementors load images from files or the Web.
ImageSourceConverter	Class that takes a string representation of an image file location and returns a ImageSource from the specified resource.
IndicatorView
InputView	The base class of a view which can take keyboard input.
InvalidNavigationException
ItemsLayout
ItemsLayoutTypeConverter
ItemsView	A View that serves as a base class for views that contain a templated list of items.
ItemsView<TVisual>	A base class for a view that contains a templated list of items.
ItemsViewScrolledEventArgs
ItemTappedEventArgs	Event arguments for the ItemTapped event.
ItemVisibilityEventArgs	Event args when an item's visibility has been changed in a ListView.
Keyboard	Default keyboard and base class for specialized keyboards, such as those for telephone numbers, email, and URLs.
KeyboardTypeConverter	A TypeConverter that converts a string into a Keyboard.
Label	A View that displays text.
Layout	Provides the base class for all Layout elements. Use Layout elements to position and size child elements in Xamarin.Forms applications.
Layout<T>	A base implementation of a layout with undefined behavior and multiple children.
LayoutOptionsConverter	Class that takes a string representation of a LayoutOptions and returns a corresponding LayoutOptions.
LinearGradientBrush
LinearItemsLayout
ListProxyChangedEventArgs
ListStringTypeConverter	Type converter for converting properly formatted string lists to lists.
ListView	An ItemsView<TVisual> that displays a collection of data as a vertical list.
MarshalingObservableCollection
MasterDetailPage	A Page that manages two panes of information: A master page that presents data at a high level, and a detail page that displays low-level details about information in the master.
Menu	Represents an application menu on platforms that support them.
MenuItem	Class that presents a menu item and associates it with a command.
MenuItemCollection	A group of related MenuItem objects.
MessagingCenter	Associates a callback on subscribers with a specific message name.
ModalEventArgs	Base class for ModalPushedEventArgs, ModalPushingEventArgs, ModalPoppedEventArgs, and ModalPoppingEventArgs.
ModalPoppedEventArgs	Arguments for the event that is raised when a modal window is popped from the navigation stack.
ModalPoppingEventArgs	Arguments for the event that is raised when a modal window is popping from the navigation stack.
ModalPushedEventArgs	Arguments for the event that is raised when a modal window is pushed onto the navigation stack.
ModalPushingEventArgs	Arguments for the event that is raised when a modal window is being pushed onto the navigation stack.
MultiBinding
MultiPage<T>	A bindable, templatable base class for pages which contain multiple sub-pages.
MultiTrigger	Class that represents a list of property and binding conditions, and a list of setters that are applied when all of the conditions in the list are met.
NamedPlatformColor
NameScopeExtensions	Extension methods for Element that adds a strongly-typed FindByName method.
NavigableElement	A Element that supports navigation.
NavigationEventArgs	EventArgs for the NavigationPage's navigation events.
NavigationPage	A Page that manages the navigation and user-experience of a stack of other pages.
On	Class that is used within `OnPlatform` tags in XAML when specifying values on platforms.
OnIdiom<T>	Provides idiom-specific value for `T` for the current target idiom.
OnPlatform<T>	Provides the platform-specific implementation of T for the current OS.
OpenGLView	A View that displays OpenGL content.
OpenSwipeEventArgs
OrientationStateTrigger
Page	A VisualElement that occupies the entire screen.
PanGestureRecognizer	A gesture recognizer for panning content that is larger than its parent view.
PanUpdatedEventArgs	Event that is raised when a pan gesture updates.
Picker	A View control for picking an element in a list.
PinchGestureRecognizer	Recognizer for pinch gestures.
PinchGestureUpdatedEventArgs	Event arguments for the PinchUpdated event.
PlatformEffect<TContainer,TControl>	Base class for platform-specific effect classes.
PointTypeConverter	A TypeConverter that converts from a string to a Point.
PoppedToRootEventArgs	EventArgs for the NavigationPage's PoppedToRoot navigation event.
PositionChangedEventArgs
ProgressBar	A View control that displays progress.
PropertyChangingEventArgs	Event arguments for the PropertyChangingEventHandler delegate.
PropertyCondition	Class that represents a value comparison against a property on the control that contains the enclosing MultiTrigger.
QueryPropertyAttribute
RadialGradientBrush
RadioButton
RadioButtonGroup
RectangleTypeConverter	A TypeConverter that converts a string to a Rectangle.
RectTypeConverter
ReferenceTypeConverter	For internal use by the Xamarin.Forms platform.
RefreshView
RelativeBindingSource
RelativeLayout	A Layout<T> that uses Constraints to layout its children.
RenderWithAttribute	Associate view with renderer.
ResolutionGroupNameAttribute	Attribute that identifies a group name, typically a company name or reversed company URL, that provides a scope for effect names.
ResourceDictionary	An IDictionary that maps identifier strings to arbitrary resource objects.
ResourceDictionary.RDSourceTypeConverter	For internal use by the Xamarin.Forms platform.
RouteFactory
Routing
RoutingEffect	Platform-independent effect that wraps an inner effect, which is usually platform-specific.
RowDefinition	An IDefinition that defines properties for a row in a Grid.
RowDefinitionCollection	A DefinitionCollection<T> for RowDefinitions.
RowDefinitionCollectionTypeConverter
ScrolledEventArgs	Arguments for the event that is raised when a window is scrolled.
ScrollToRequestedEventArgs	Arguments for the event that is raised when a scroll is requested.
ScrollToRequestEventArgs
ScrollView	An element capable of scrolling if its Content requires.
SearchBar	A View control that provides a search box.
SearchHandler	Default implementation of ISearchHandlerController.
SelectableItemsView
SelectedItemChangedEventArgs	Event arguments for the ItemSelected event.
SelectedPositionChangedEventArgs	Event arguments for positional scrolling events.
SelectionChangedEventArgs
Setter	Represents an assignment of a property to a value, typically in a style or in response to a trigger.
SettersExtensions	Defines extensions methods for IList<Setter>
Shell	A Page that provides fundamental UI features that most applications require, leaving you to focus on the application's core workload.
ShellAppearance
ShellContent	Corresponds to a ContentPage contained in a ShellSection.
ShellGroupItem	A BaseShellItem that has FlyoutDisplayOptions. Base class for ShellItem and ShellSection.
ShellItem	One or more items in the flyout. Contained within a Shell.
ShellNavigatedEventArgs	Arguments for the OnNavigated(ShellNavigatedEventArgs) event.
ShellNavigatingDeferral
ShellNavigatingEventArgs	Arguments for the OnNavigating(ShellNavigatingEventArgs) event.
ShellNavigationState	A URI representing either the current page or a destination for navigation in a Shell application.
ShellSection	Grouped content in a Shell application, navigable by bottom tabs.
SizeTypeConverter	A TypeConverter that can convert a string into a Size object.
Slider	A View control that inputs a linear value.
SolidColorBrush
Span	Represents a section of a FormattedString.
StackLayout	A Layout<T> that positions child elements in a single line which can be oriented vertically or horizontally.
StateTrigger
StateTriggerBase
Stepper	A View control that inputs a discrete value, constrained to a range.
StreamImageSource	ImageSource that loads an image from a System.IO.Stream.
StructuredItemsView
Style	Class that contains triggers, setters, and behaviors that completely or partially define the appearance and behavior of a class of visual elements.
SwipeChangingEventArgs
SwipedEventArgs	Arguments for swipe events.
SwipeEndedEventArgs
SwipeGestureRecognizer	Recognizer for swipe gestures.
SwipeItem
SwipeItems
SwipeItemView
SwipeStartedEventArgs
SwipeView
Switch	A View control that provides a toggled value.
SwitchCell	A Cell with a label and an on/off switch.
Tab
TabBar
TabbedPage	MultiPage<T> that displays an array of tabs across the top of the screen, each of which loads content onto the screen.
TabIndexExtensions	Extensions methods supporting iteration and retrieval of tab indexes.
TableRoot	A TableSection that contains either a table section or the entire table.
TableSection	A logical and visible section of a TableView.
TableSectionBase	Abstract base class defining a table section.
TableSectionBase<T>	Table section that contains instances of type T that are rendered by Xamarin.Forms.
TableView	A View that holds rows of Cell elements.
TapGestureRecognizer	Provides tap gesture recognition and events.
TappedEventArgs	Arguments for the ItemTapped event.
TemplateBinding	Binds a template property to the parent of the view that owns a ControlTemplate.
TemplatedPage	A page that displays full-screen content with a control template, and the base class for ContentPage .
TemplatedView	A view that displays content with a control template, and the base class for ContentView.
TemplateExtensions	Extension class for DataTemplate, providing a string-based shortcut method for defining a Binding.
TextAlignmentConverter	Converts a string representation of a text alignment to a TextAlignment.
TextCell	A Cell with primary Text and Detail text.
TextChangedEventArgs	Event arguments for `TextChanged` events. Provides old and new text values.
TextDecorationConverter	A TypeConverter subclass that can convert between a string and a TextDecorations object.
ThicknessTypeConverter	A TypeConverter that converts from a string to a Thickness.
TimePicker	A View control that provides time picking.
ToggledEventArgs	Event arguments for Toggled and OnChanged events.
ToolbarItem	An item in a toolbar or displayed on a Page.
Trigger	Class that represents a property condition and an action that is performed when the condition is met.
TriggerAction	A base class for user-defined actions that are performed when a trigger condition is met.
TriggerAction<T>	A generic base class for user-defined actions that are performed when a trigger condition is met.
TriggerBase	Base class for classes that contain a condition and a list of actions to perform when the condition is met.
TypeConverter	Abstract base class whose subclasses can convert values between different types.
TypeConverterAttribute	Attribute that specifies the type of TypeConverter used by its target.
TypeTypeConverter	Class that takes a string representation of a System.Type and returns a corresponding System.Type.
UnsolvableConstraintsException	Exception indicating that the Constraints specified cannot be simultaneously satisfied.
UriImageSource	An ImageSource that loads an image from a URI, caching the result.
UriTypeConverter	A TypeConverter that converts from a string or System.Uri to a System.Uri.
UrlWebViewSource	A WebViewSource bound to a URL.
ValueChangedEventArgs	Event arguments for `ValueChanged` events. Provides both old and new values.
View	A visual element that is used to place layouts and controls on the screen.
ViewCell	A Cell containing a developer-defined View.
ViewExtensions	Extension methods for Views, providing animatable scaling, rotation, and layout functions.
VisualAttribute
VisualElement	A Element that occupies an area on the screen, has a visual appearance, and can obtain touch input.
VisualElement.FocusRequestArgs	Contains event arguments for the FocusChangeRequested event.
VisualElement.VisibilityConverter	Converts a string representation of a visual element visibility to a Boolean that represents the visibility of the element.
VisualMarker	Contains the IVisual types implemented by the Xamarin Forms team and the default IVisual types used by the Visual system.
VisualMarker.DefaultVisual	IVisual marker type used to indicate for a View to render using a default renderer.
VisualMarker.MaterialVisual	IVisual marker type used to indicate for a View to render using a material renderer.
VisualState	Contains a named visual state that applies a list of setters to an element in order to correlate a state with an appearance.
VisualStateGroup	Contains a list of related visual states that can be applied to a visual element.
VisualStateGroupList	Contains a list of visual state groups for an application.
VisualStateManager	Manages visual state groups and transitions controls between states.
VisualStateManager.CommonStates
VisualTypeConverter	A TypeConverter that can convert a string into a IVisual object.
WeakEventManager
WebNavigatedEventArgs	Class that contains arguments for the event that is raised after web navigation completes.
WebNavigatingEventArgs	Class that contains arguments for the event that is raised after web navigation begins.
WebNavigationEventArgs	TClass that contains arguments for the event that is when web navigation begins.
WebView	A View that presents HTML content.
WebViewSource	Abstract class whose subclasses provide the data for a WebView.
WebViewSourceTypeConverter	A TypeConverter that converts a string to a UrlWebViewSource.
XmlnsDefinitionAttribute	Attribute specifying the mapping between an XML namespace and a CLR namespace.
XmlnsPrefixAttribute

Structs

Color	Class that represents a color and exposes it as RGBA and HSL values.
CornerRadius	Contains methods and properties for specifying corner radiuses.
FlexBasis	Struct that represents an absolute or relative element size.
Font	The font used to display text.
GridLength	Used to define the size (width/height) of Grid ColumnDefinition and RowDefinition.
LayoutOptions	A struct whose static members define various alignment and expansion options.
Point	Struct defining a 2-D point as a pair of doubles.
Rect
Rectangle	Struct defining a rectangle, using doubles.
Region	Represents a visual region in a Xamarin.Forms UI.
Size	Struct defining height and width as a pair of doubles.
SizeRequest	Struct that defines minimum and maximum Sizes.
Thickness	Struct defining thickness around the edges of a Rectangle using doubles.
Vec2	Struct defining X and Y double values.

Interfaces

AbsoluteLayout.IAbsoluteList<T>	List interface with overloads for adding elements to an absolute layout.
Grid.IGridList<T>	List interface with overloads for adding elements to a grid.
IAnimatable	Defines an interface for elements that can be animated.
IAppearanceObserver
IAppIndexingProvider	This interface is for internal use by platform renderers.
IApplicationController	For internal use by platform renderers.
IAppLinkEntry	Interface that represents a deep application link in an app link search index.
IAppLinks	Interface that defines the methods that are required for registering and deregistering links to content in apps.
IBorderElement
IButtonController	For internal use by platform renderers.
ICellController	For internal use by platform renderers.
IConfigElement<T>	This interface is for internal use by platform renderers.
IConfigPlatform	Base interface for marker classes that identify target platforms for platform specific effects.
IDecorableTextElement	Interface for classes supporting TextDecorations.
IDefinition	Interface defining the type of RowDefinition and ColumnDefinition.
IDispatcher
IDispatcherProvider
IEditorController	For internal use by platform renderers.
IEffectControlProvider	When implemented in a renderer, registers a platform-specific effect on an element.
IElementConfiguration<TElement>	Interface for returning the platform-specific instance of a Xamarin.Forms type.
IElementController	For internal use by platform renderers.
IEmbeddedFontLoader
IEntryCellController	For internal use by platform renderers.
IEntryController	For internal use by platform renderers.
IExtendedTypeConverter	Base class for type converters.
IFlyoutBehaviorObserver
IFlyoutPageController
IGestureRecognizer	The base interface all gesture recognizers must implement.
IGestureRecognizers
IGridController	For internal use by platform renderers.
IImageController	For internal use by platform renderers.
IImageElement
IItemsLayout
IItemsView<T>	This interface is for internal use by platform renderers.
IItemViewController	For internal use by platform renderers.
ILayout	Interface indicating layout behavior and exposing the LayoutChanged event.
ILayoutController	For internal use by platform renderers.
IListProxy	This interface is for internal use by platform renderers.
IListViewController	For internal use by platform renderers.
IMasterDetailPageController	For internal use by platform renderers.
IMenuItemController	For internal use by platform renderers.
IMessagingCenter	Enables view models and other components to communicate by adhering to a message contract.
IMultiPageController<T>	Base class for multipage controllers.
IMultiValueConverter
INativeElementView	Interface that contains a read-only property that returns the platform-specific native view for a Xamarin.Forms element.
INavigation	Interface abstracting platform-specific navigation.
INavigationPageController	For internal use by platform renderers.
IOpenGlViewController	For internal use by platform renderers.
IPageContainer<T>	Interface defining a container for Pages and exposing a CurrentPage property.
IPageController	For internal use by platform renderers.
IPanGestureController	For internal use by platform renderers.
IPinchGestureController	For internal use by platform renderers.
IPlatformElementConfiguration<TPlatform,TElement>	Marker interface for returning platform-specific configuration elements.
IQueryAttributable
IRegisterable	Internally-used flagging interface indicating types that can be registered with the internal Registrar.
IScrollViewController	For internal use by platform renderers.
ISearchBarController	For internal use by platform renderers.
ISearchHandlerController	Defines the interface for controlling the behavior of the search handler.
IShellAppearanceElement	Interface defining colors for the tab bar in Shell applications.
IShellContentController	Extends IElementController to define methods appropriate to a content page in Shell applications.
IShellContentInsetObserver	Defines an interface for observing changes to inset dimensions.
IShellController	Extends IPageController for Shell applications.
IShellItemController	Extends IElementController to work with the parts of a Shell application.
IShellSectionController	Extends IElementController with methods specific to Shell applications.
ISliderController
IStreamImageSource	This interface is for internal use by platform renderers.
ISwipeGestureController	For internal use by platform renderers.
ISwipeItem
ISwipeViewController
ITableModel	This interface is for internal use by platform renderers.
ITableViewController	For internal use by platform renderers.
ITabStopElement
ITemplatedItemsList<TItem>	This interface is for internal use by platform renderers.
ITemplatedItemsListScrollToRequestedEventArgs	This interface is for internal use by platform renderers.
ITemplatedItemsView<TItem>	This interface is for internal use by platform renderers.
IValueConverter	Interface defining methods for two-way value conversion between types.
IViewContainer<T>	The type of element that can be added to the container.
IViewController	This interface is for internal use by platform renderers.
IVisual
IVisualElementController	For internal use by platform renderers.
IWebViewController	For internal use by platform renderers.
IWebViewDelegate	This interface is for internal use by platform renderers.
RelativeLayout.IRelativeList<T>	An System.Collections.Generic.IList`1 of Views used by a RelativeLayout.

Enums

AbsoluteLayoutFlags	Flags used to modify how layout bounds are interpreted in an AbsoluteLayout.
AccessKeyPlacement	Enumerates access key placement relative to the control that the access key describes.
Aspect	Defines how an image is displayed.
BindingMode	The direction of changes propagation for bindings.
Button.ButtonContentLayout.ImagePosition	Enumerates image locations within a button.
ButtonsMask	Flag values that represent mouse buttons.
ClearButtonVisibility
ConstraintType	Enumeration specifying whether a constraint is constant, relative to a view, or relative to its parent.
DataPackageOperation
DependencyFetchTarget	Enumeration specifying whether Get<T>(DependencyFetchTarget) should return a reference to a global or new instance.
EditorAutoSizeOption	Enumerates values that control whether an editor will change size to accommodate input as the user enters it.
EffectiveFlowDirection	Enumerates flags that indicate whether the layout direction was explicitly set, and whether the layout direction is right-to-left.
FlexAlignContent	Enumerates values that control how multiple rows or columns of child elements are aligned.
FlexAlignItems	Enumerates values that control the alignment of child elements.
FlexAlignSelf	Enumerates values that control how and whether a child element overrides alignment attributes applied by its parent.
FlexDirection	Enumerates values that specify row and columen flex layout directions, relative to the directions for the device locale.
FlexJustify	Enumerates values that describe how child elements are justified when there is extra space around them.
FlexPosition	Enumerates values that control how layout coordinates are interpreted when specifying the positions of child elements.
FlexWrap	Enumerates values that control whether and how to wrap items in a FlexLayout.
FlowDirection	Enumerates values that control the layout direction for views.
FlyoutBehavior	Enumeration of modes for the root menu of a Shell application.
FlyoutDisplayOptions	Enumerates display modes for the flyout in a Shell appication.
FlyoutHeaderBehavior	Enumeration of modes followed by the FlyoutHeader.
FlyoutLayoutBehavior
FontAttributes	Enumerates values that describe font styles.
GestureState	Enumeration specifying the various states of a gesture.
GestureStatus	Enumerates possible gesture states.
GridUnitType	Enumerates values that control how the Value property is interpreted for row and column definitions.
IndicatorShape
InitializationFlags
ItemSizingStrategy
ItemsLayoutOrientation
ItemsUpdatingScrollMode
KeyboardFlags	Enumerates keyboard option flags that controls capitalization, spellcheck, and suggestion behavior.
LayoutAlignment	Values that represent LayoutAlignment.
LineBreakMode	Enumeration specifying various options for line breaking.
ListViewCachingStrategy	Enumerates caching strategies for a ListView.
ListViewSelectionMode	Enumerates values that control whether items in a list view can or cannot be selected.
MasterBehavior	Enumerates values that control how detail content is displayed in a master-detail page.
MeasureFlags	Enumerates values that tell whether margins are included when laying out windows.
NamedSize	Represents pre-defined font sizes.
OpenSwipeItem
OSAppTheme
PresentationMode
RelativeBindingSourceMode
ReturnType	Enumerates return button styles.
ScrollBarVisibility	Enumerates conditions under which scroll bars will be visible.
ScrollMode
ScrollOrientation	Enumeration specifying vertical or horizontal scrolling directions.
ScrollToMode	Enumerates values that describe how a scroll request is made.
ScrollToPosition	Enumerates values that describe a scroll request.
SearchBoxVisibility
SelectionMode
SeparatorVisibility	Enumerates values that control the visibility of list item separators.
ShellNavigationSource	Enumerates reasons for a navigation event in Shell applications.
SnapPointsAlignment
SnapPointsType
StackOrientation	The orientations the a StackLayout can have.
Stretch
SweepDirection
SwipeBehaviorOnInvoked
SwipeDirection	Enumerates swipe directions.
SwipeMode
TableIntent	TableIntent provides hints to the renderer about how a table will be used.
TabsStyle	Enumerates tab styles for tabbed pages.
TargetIdiom	Indicates the type of device Xamarin.Forms is working on.
TargetPlatform	Indicates the kind of OS Xamarin.Forms is currently working on.
TextAlignment	Enumerates values that control text alignment.
TextDecorations	Flagging enumeration defining text decorations.
TextTransform
TextType
ToolbarItemOrder	Enumeration specifying whether the ToolbarItem appears on the primary toolbar surface or secondary.
ViewState	Deprecated. Do not use.
WebNavigationEvent	Contains values that indicate why a navigation event was raised.
WebNavigationResult	Enumerates values that indicate the outcome of a web navigation.

Delegates

BindableProperty.BindingPropertyChangedDelegate	Delegate for BindableProperty.PropertyChanged.
BindableProperty.BindingPropertyChangedDelegate<TPropertyType>	Strongly-typed delegate for BindableProperty.PropertyChanged.
BindableProperty.BindingPropertyChangingDelegate	Delegate for BindableProperty.PropertyChanging.
BindableProperty.BindingPropertyChangingDelegate<TPropertyType>	Strongly-typed delegate for BindableProperty.PropertyChanging.
BindableProperty.CoerceValueDelegate	Delegate for BindableProperty.CoerceValue.
BindableProperty.CoerceValueDelegate<TPropertyType>	Strongly-typed delegate for BindableProperty.CoerceValue.
BindableProperty.CreateDefaultValueDelegate	Strongly typed delegate for BindableProperty.DefaultValueCreator.
BindableProperty.CreateDefaultValueDelegate<TDeclarer,TPropertyType>	Delegate for BindableProperty.DefaultValueCreator.
BindableProperty.ValidateValueDelegate	Delegate for BindableProperty.ValidateValue.
BindableProperty.ValidateValueDelegate<TPropertyType>	Strongly-typed delegate for BindableProperty.ValidateValue.
CollectionSynchronizationCallback	Delegate for callback in EnableCollectionSynchronization(IEnumerable, Object, CollectionSynchronizationCallback).
PropertyChangingEventHandler	Delegate for the PropertyChanging event.

Remarks

Xamarin.Forms is a cross-platform, natively-backed UI toolkit abstraction that allows developers to create user interfaces that can be shared across Android, iOS, and Windows Phone. Because the user interfaces use the native controls of the target platforms, they have the appearance and, importantly, the responsiveness of natively built apps.

Xamarin.Forms Solution Architecture

Cross-Platform Project

The user-experience of a Xamarin.Forms application is usually defined in a cross-platform shared project (either a Portable Class Library or a Shared Project) and combined with platform-specific projects that, at the least, initialize the native platform rendering (note the call to Forms.Init() in the platform code samples below) and, more generally, extend the user-experience and user-interface in platform-specific manners (for instance, by accessing platform-specific sensors or capabilities).

For example, the developer can create a cross-platform Xamarin.Forms Label and display it with the following code in the shared project:

public class App : Xamarin.Forms.Application
{
    public App ()
    {
        MainPage = new ContentPage
        {
            Content = new Label
                {
                    Text = "Welcome to Xamarin Forms!",
                    VerticalOptions = LayoutOptions.CenterAndExpand,
                    HorizontalOptions = LayoutOptions.CenterAndExpand,
                },
        };
    }
}

This code results in a centered label on the target platforms:

While more complicated layouts with more useful user interfaces are more typical, this example is useful for clearly illustrating the shared and platform-specific code that Xamarin.Forms uses to create and display the code on the target platforms. The code in the following discussion is created by Visual Studio in the target platform projects when the developer creates a new Xamarin.Forms project. In each case, a platform-specific Forms.Init() method is called to intitialize forms before any other method that depends on Xamarin.Forms is called.

iOS Platform Code

On the iOS platform, Visual Studio registers a subclass of the framework class Xamarin.Forms.Platform.iOS.FormsApplicationDelegate as the entry point of the application, and immediately makes a call to Xamarin.Forms.Forms.Init.

[Register("AppDelegate")]
public partial class AppDelegate : global::Xamarin.Forms.Platform.iOS.FormsApplicationDelegate
{
    public override bool FinishedLaunching(UIApplication app, NSDictionary options)
    {
        global::Xamarin.Forms.Forms.Init();
        LoadApplication(new App());

        return base.FinishedLaunching(app, options);
    }
}

Android Platform Code

The entry point on Android is a subclass of the framework class Xamarin.Forms.Platform.Android.FormsAppCompatActivity, and its OnCreate method must configure the tab bar and toolbars and call its base method before calling Forms.Init.

[Activity(Label = "HelloXamarinFormsWorld.Droid", Icon = "@drawable/icon", Theme = "@style/MyTheme", MainLauncher = true, ConfigurationChanges = ConfigChanges.ScreenSize | ConfigChanges.Orientation)]
public class MainActivity : global::Xamarin.Forms.Platform.Android.FormsAppCompatActivity
{
    protected override void OnCreate(Bundle bundle)
    {
        TabLayoutResource = Resource.Layout.Tabbar;
        ToolbarResource = Resource.Layout.Toolbar;

        base.OnCreate(bundle);

        global::Xamarin.Forms.Forms.Init(this, bundle);

        LoadApplication(new App());
    }

    protected override void OnActivityResult(int requestCode, Result resultCode, Intent data)
    {
        base.OnActivityResult(requestCode, resultCode, data);
    }
}

UWP Code

The entry point for a Xamarin.Forms app on UWP is just the constructor for a Windows.UI.Xaml.Application in App.xaml.cs in the UWP platform project. However, the application lifecycle on UWP is such that the call to Forms.Init must take place inside the OnLaunched method, and is guarded against being run more than once. The necessary code is beyond the scope of this documentation, but the curious developer is encouraged to create a test Xamarin.Forms solution and study the code in the App.xaml.cs file for more details

Elements in Xamarin.Forms

Important types in the Xamarin.Forms namespace include Page, View, and Layout. Pages typically correspond with controller objects (Activities in the Android world, UIViewControllers in the iOS world), Views with controls or widgets, and Layouts arrange Views on other Views. These types are all derived from Element.

Model-View-ViewModel and Xamarin.Forms

Application developers use the Model-View-ViewModel (MVVM) pattern to create Xamarin.Forms apps that cleanly separate the concerns of data presentation and user interface from the concerns of data storage and manipulation. The Xamarin.Forms framework enables this by providing, among a few other related types, the BindableObject and BindableProperty classes. Objects that inherit from BindableObject can be bound to members of type BindableProperty on other objects.

A BindableObject maintains dictionary of BindableProperty names and an association with their corresponding binding contexts--simply the object on which the BindableProperty is defined and that the application developer has assigned to the BindingContext property--through a Binding. See BindableObject for more information.

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