BlockAdorner Class

Definition

Namespace:Avalonia.Controls.Documents.Primitives.Adorners

Assembly:Avalonia.Controls.Documents

Package:Avalonia.Controls.Documents

Base class for editor-driven block decorations that participate in the Avalonia property system and logical tree.

public class BlockAdorner

Inheritance: object -> AvaloniaObject -> Animatable -> StyledElement -> BlockAdorner

Remarks

Subclasses decorate realized Avalonia.Controls.Documents.Primitives.DocumentNodes.DocumentNode instances without modifying the block data model. A single adorner can provide immediate-mode rendering via Avalonia.Controls.Documents.Primitives.Adorners.BlockAdorner.Render(Avalonia.Media.DrawingContext,Avalonia.Controls.Documents.Primitives.DocumentNodes.DocumentNode,Avalonia.Rect), interactive controls via Avalonia.Controls.Documents.Primitives.Adorners.BlockAdorner.CreateControl(Avalonia.Controls.Documents.Primitives.DocumentNodes.DocumentNode)/Avalonia.Controls.Documents.Primitives.Adorners.BlockAdorner.UpdateControl(Avalonia.Controls.Control,Avalonia.Controls.Documents.Primitives.DocumentNodes.DocumentNode,Avalonia.Rect), or both.

Each adorner declares which block categories it targets via Avalonia.Controls.Documents.Primitives.Adorners.BlockAdorner.TargetAreas and whether it renders on all matching blocks or only the current context block via Avalonia.Controls.Documents.Primitives.Adorners.BlockAdorner.Visibility.

Because Avalonia.Controls.Documents.Primitives.Adorners.BlockAdorner extends Avalonia.StyledElement, adorners added to a Avalonia.Controls.Documents.Primitives.Adorners.BlockAdornerLayer join its logical tree and can receive styles and dynamic resources from ancestor resource dictionaries.

Methods

Name	Description
ApplyStyling	Applies styling to the control if the control is initialized and styling is not already applied. Inherited from StyledElement.
BeginInit	Inherited from StyledElement.
Bind (8 overloads)	Binds a Avalonia.AvaloniaProperty to an Avalonia.Data.BindingBase. Inherited from AvaloniaObject.
CheckAccess	Returns a value indicating whether the current thread is the UI thread. Inherited from AvaloniaObject.
ClearValue (4 overloads)	Clears a Avalonia.AvaloniaProperty's local value. Inherited from AvaloniaObject.
CoerceValue	Coerces the specified Avalonia.AvaloniaProperty. Inherited from AvaloniaObject.
CreateControl	Creates an interactive control overlaid on a document node, or returns null if this adorner has no interactive component. Called once per (adorner, node) pair when the node first becomes realized and passes all filters.
EndInit	Inherited from StyledElement.
Equals	Compares two objects using reference equality. Inherited from AvaloniaObject.
GetBaseValue	Inherited from AvaloniaObject.
GetHashCode	Gets the hash code for the object. Inherited from AvaloniaObject.
GetValue (3 overloads)	Gets a Avalonia.AvaloniaProperty value. Inherited from AvaloniaObject.
IsAnimating	Checks whether a Avalonia.AvaloniaProperty is animating. Inherited from AvaloniaObject.
IsSet	Checks whether a Avalonia.AvaloniaProperty is set on this object. Inherited from AvaloniaObject.
Render	Draws the immediate-mode decoration for a single block. Adorners that only provide interactive controls can leave this as a no-op.
SetCurrentValue (2 overloads)	Sets the value of a dependency property without changing its value source. Inherited from AvaloniaObject.
SetValue (3 overloads)	Sets a Avalonia.AvaloniaProperty value. Inherited from AvaloniaObject.
ShouldRender	Performs a final per-node check after target-area and visibility filtering has passed. Use this for fine-grained logic such as skipping blocks that already have visible borders.
TryGetResource	Inherited from StyledElement.
UpdateControl	Updates an interactive control's state after a layout pass. Only called when Avalonia.Controls.Documents.Primitives.Adorners.BlockAdorner.CreateControl(Avalonia.Controls.Documents.Primitives.DocumentNodes.DocumentNode) previously returned a non-null value for this node.
VerifyAccess	Checks that the current thread is the UI thread and throws if not. Inherited from AvaloniaObject.

CreateControl Method

Creates an interactive control overlaid on a document node, or returns null if this adorner has no interactive component. Called once per (adorner, node) pair when the node first becomes realized and passes all filters.

public Avalonia.Controls.Control CreateControl(Avalonia.Controls.Documents.Primitives.DocumentNodes.DocumentNode node)

Parameters

node Avalonia.Controls.Documents.Primitives.DocumentNodes.DocumentNode

The realized document node to adorn.

Returns

Avalonia.Controls.Control

A new control, or null for non-interactive adorners.

Render Method

Draws the immediate-mode decoration for a single block. Adorners that only provide interactive controls can leave this as a no-op.

public void Render(Avalonia.Media.DrawingContext context, Avalonia.Controls.Documents.Primitives.DocumentNodes.DocumentNode node, Avalonia.Rect blockBounds)

Parameters

context Avalonia.Media.DrawingContext

The drawing context, already transformed into text-view coordinates.

node Avalonia.Controls.Documents.Primitives.DocumentNodes.DocumentNode

The realized document node being decorated.

blockBounds Avalonia.Rect

The node bounds in text-view coordinates.

ShouldRender Method

Performs a final per-node check after target-area and visibility filtering has passed. Use this for fine-grained logic such as skipping blocks that already have visible borders.

public bool ShouldRender(Avalonia.Controls.Documents.Primitives.DocumentNodes.DocumentNode node)

Parameters

node Avalonia.Controls.Documents.Primitives.DocumentNodes.DocumentNode

The realized document node to test.

Returns

bool

true if the adorner should render for this node.

UpdateControl Method

Updates an interactive control's state after a layout pass. Only called when Avalonia.Controls.Documents.Primitives.Adorners.BlockAdorner.CreateControl(Avalonia.Controls.Documents.Primitives.DocumentNodes.DocumentNode) previously returned a non-null value for this node.

public void UpdateControl(Avalonia.Controls.Control control, Avalonia.Controls.Documents.Primitives.DocumentNodes.DocumentNode node, Avalonia.Rect blockBounds)

Parameters

control Avalonia.Controls.Control

The control previously returned by Avalonia.Controls.Documents.Primitives.Adorners.BlockAdorner.CreateControl(Avalonia.Controls.Documents.Primitives.DocumentNodes.DocumentNode).

node Avalonia.Controls.Documents.Primitives.DocumentNodes.DocumentNode

The realized document node.

blockBounds Avalonia.Rect

The node bounds in text-view coordinates.

Properties

Name	Description
ActualThemeVariant	Gets the UI theme that is currently used by the element, which might be different than the RequestedThemeVariantProperty. Inherited from StyledElement.
Classes	Gets or sets the styled element's classes. Inherited from StyledElement.
DataContext	Gets or sets the control's data context. Inherited from StyledElement.
Dispatcher	Returns the Avalonia.AvaloniaObject.Dispatcher that this Avalonia.AvaloniaObject is associated with. Inherited from AvaloniaObject.
IsEnabled	Gets or sets whether this adorner takes part in rendering. When false, the layer skips it entirely.
IsInitialized	Gets a value that indicates whether the element has finished initialization. Inherited from StyledElement.
Item	Inherited from AvaloniaObject.
Name	Gets or sets the name of the styled element. Inherited from StyledElement.
Parent	Gets the styled element's logical parent. Inherited from StyledElement.
Resources	Gets or sets the styled element's resource dictionary. Inherited from StyledElement.
StyleKey	Gets the type by which the element is styled. Inherited from StyledElement.
Styles	Gets the styles for the styled element. Inherited from StyledElement.
TargetAreas	Gets which block categories this adorner targets. The layer skips blocks whose resolved category does not intersect with this value.
TemplatedParent	Gets the styled element whose lookless template this styled element is part of. Inherited from StyledElement.
Theme	Gets or sets the theme to be applied to the element. Inherited from StyledElement.
Transitions	Gets or sets the property transitions for the control. Inherited from Animatable.
Visibility	Gets or sets whether this adorner renders on every matching block or only on the current context block.
ZIndex	Gets or sets the Z-index for render ordering among adorners. Higher values render on top.

IsEnabled Property

Gets or sets whether this adorner takes part in rendering. When false, the layer skips it entirely.

public bool IsEnabled { get; set; }

TargetAreas Property

Gets which block categories this adorner targets. The layer skips blocks whose resolved category does not intersect with this value.

public Avalonia.Controls.Documents.Primitives.Adorners.ToolbarTargetAreas TargetAreas { get; set; }

Visibility Property

Gets or sets whether this adorner renders on every matching block or only on the current context block.

public Avalonia.Controls.Documents.Primitives.Adorners.BlockAdornerVisibility Visibility { get; set; }

ZIndex Property

Gets or sets the Z-index for render ordering among adorners. Higher values render on top.

public int ZIndex { get; set; }

Fields

Name	Description
DataContextProperty	Defines the Avalonia.StyledElement.DataContext property. Inherited from StyledElement.
IsEnabledProperty	Defines the Avalonia.Controls.Documents.Primitives.Adorners.BlockAdorner.IsEnabled property.
NameProperty	Defines the Avalonia.StyledElement.Name property. Inherited from StyledElement.
ParentProperty	Defines the Avalonia.StyledElement.Parent property. Inherited from StyledElement.
TemplatedParentProperty	Defines the Avalonia.StyledElement.TemplatedParent property. Inherited from StyledElement.
ThemeProperty	Defines the Avalonia.StyledElement.Theme property. Inherited from StyledElement.
TransitionsProperty	Defines the Avalonia.Animation.Animatable.Transitions property. Inherited from Animatable.
VisibilityProperty	Defines the Avalonia.Controls.Documents.Primitives.Adorners.BlockAdorner.Visibility property.
ZIndexProperty	Defines the Avalonia.Controls.Documents.Primitives.Adorners.BlockAdorner.ZIndex property.

IsEnabledProperty Field

Defines the Avalonia.Controls.Documents.Primitives.Adorners.BlockAdorner.IsEnabled property.

public Avalonia.StyledProperty<bool> IsEnabledProperty

VisibilityProperty Field

Defines the Avalonia.Controls.Documents.Primitives.Adorners.BlockAdorner.Visibility property.

public Avalonia.StyledProperty<Avalonia.Controls.Documents.Primitives.Adorners.BlockAdornerVisibility> VisibilityProperty

ZIndexProperty Field

Defines the Avalonia.Controls.Documents.Primitives.Adorners.BlockAdorner.ZIndex property.

public Avalonia.StyledProperty<int> ZIndexProperty

Events

Name	Description
ActualThemeVariantChanged	Raised when the theme variant is changed on the element or an ancestor of the element. Inherited from StyledElement.
AttachedToLogicalTree	Raised when the styled element is attached to a rooted logical tree. Inherited from StyledElement.
Changed	Raised when the adorner's visual state changes and the layer should repaint.
DataContextChanged	Occurs when the Avalonia.StyledElement.DataContext property changes. Inherited from StyledElement.
DetachedFromLogicalTree	Raised when the styled element is detached from a rooted logical tree. Inherited from StyledElement.
Initialized	Occurs when the styled element has finished initialization. Inherited from StyledElement.
PropertyChanged	Raised when a Avalonia.AvaloniaProperty value changes on this object. Inherited from AvaloniaObject.
ResourcesChanged	Occurs when a resource in this styled element or a parent styled element has changed. Inherited from StyledElement.

Changed Event

Raised when the adorner's visual state changes and the layer should repaint.

public event EventHandler Changed