InkResponseModifier class

An area of a Material that responds to touch. Has a configurable shape and can be configured to clip splashes that extend outside its bounds or not.

For a variant of this widget that is specialized for rectangular areas that always clip splashes, see InkWell.

An InkResponse widget does two things when responding to a tap:

• It starts to animate a highlight. The shape of the highlight is determined by highlightShape. If it is a BoxShape.circle, the default, then the highlight is a circle of fixed size centered in the InkResponse. If it is BoxShape.rectangle, then the highlight is a box the size of the InkResponse itself, unless getRectCallback is provided, in which case that callback defines the rectangle. The color of the highlight is set by highlightColor.

• Simultaneously, it starts to animate a splash. This is a growing circle initially centered on the tap location. If this is a containedInkWell, the splash grows to the radius while remaining centered at the tap location. Otherwise, the splash migrates to the center of the box as it grows.

The following two diagrams show how InkResponse looks when tapped if the highlightShape is BoxShape.circle (the default) and containedInkWell is false (also the default).

The first diagram shows how it looks if the InkResponse is relatively large:

The second diagram shows how it looks if the InkResponse is small:

The main thing to notice from these diagrams is that the splashes happily exceed the bounds of the widget (because containedInkWell is false).

The following diagram shows the effect when the InkResponse has a highlightShape of BoxShape.rectangle with containedInkWell set to true. These are the values used by InkWell.

The InkResponse widget must have a Material widget as an ancestor. The Material widget is where the ink reactions are actually painted. This matches the Material Design premise wherein the Material is what is actually reacting to touches by spreading ink.

If a Widget uses this class directly, it should include the following line at the top of its build function to call debugCheckHasMaterial:

assert(debugCheckHasMaterial(context));

Troubleshooting

The ink splashes aren't visible!

If there is an opaque graphic, e.g. painted using a Container, Image, or DecoratedBox, between the Material widget and the InkResponse widget, then the splash won't be visible because it will be under the opaque graphic. This is because ink splashes draw on the underlying Material itself, as if the ink was spreading inside the material.

The Ink widget can be used as a replacement for Image, Container, or DecoratedBox to ensure that the image or decoration also paints in the Material itself, below the ink.

If this is not possible for some reason, e.g. because you are using an opaque CustomPaint widget, alternatively consider using a second Material above the opaque widget but below the InkResponse (as an ancestor to the ink response). The MaterialType.transparency material kind can be used for this purpose.

See also:

• GestureDetector, for listening for gestures without ink splashes.
• ElevatedButton and TextButton, two kinds of buttons in Material Design.
• IconButton, which combines InkResponse with an Icon.

Inheritance

• Object
• DiagnosticableTree
• Widget
• StatelessWidget
• SingleChildStatelessModifier
• InkResponseModifier

Implementers

• InkWellModifier

Available extensions

• ModifierTransformer

Constructors

InkResponseModifier({Key? key, Widget? child, Key? modifierKey, GestureTapCallback? onTap, GestureTapDownCallback? onTapDown, GestureTapUpCallback? onTapUp, GestureTapCallback? onTapCancel, GestureTapCallback? onDoubleTap, GestureLongPressCallback? onLongPress, ValueChanged<bool>? onHighlightChanged, ValueChanged<bool>? onHover, MouseCursor? mouseCursor, bool containedInkWell = false, BoxShape highlightShape = BoxShape.circle, double? radius, BorderRadius? borderRadius, ShapeBorder? customBorder, Color? focusColor, Color? hoverColor, Color? highlightColor, MaterialStateProperty<Color?>? overlayColor, Color? splashColor, InteractiveInkFeatureFactory? splashFactory, bool enableFeedback = true, bool excludeFromSemantics = false, FocusNode? focusNode, bool canRequestFocus = true, ValueChanged<bool>? onFocusChange, bool autofocus = false, MaterialStatesController? statesController})

Creates an area of a Material that responds to touch.

const

Properties

autofocus → bool

True if this widget will be selected as the initial focus when no other node in its scope is currently focused.

final

borderRadius → BorderRadius?

The clipping radius of the containing rect. This is effective only if customBorder is null.

final

canRequestFocus → bool

If true, this widget may request the primary focus.

final

containedInkWell → bool

Whether this ink response should be clipped its bounds.

final

customBorder → ShapeBorder?

The custom clip border which overrides borderRadius.

final

enableFeedback → bool

Whether detected gestures should provide acoustic and/or haptic feedback.

final

excludeFromSemantics → bool

Whether to exclude the gestures introduced by this widget from the semantics tree.

final

focusColor → Color?

The color of the ink response when the parent widget is focused. If this property is null then the focus color of the theme, ThemeData.focusColor, will be used.

final

focusNode → FocusNode?

An optional focus node to use as the focus node for this widget.

final

hashCode → int

The hash code for this object.

no setter, inherited

highlightColor → Color?

The highlight color of the ink response when pressed. If this property is null then the highlight color of the theme, ThemeData.highlightColor, will be used.

final

highlightShape → BoxShape

The shape (e.g., circle, rectangle) to use for the highlight drawn around this part of the material when pressed, hovered over, or focused.

final

hoverColor → Color?

The color of the ink response when a pointer is hovering over it. If this property is null then the hover color of the theme, ThemeData.hoverColor, will be used.

final

key → Key?

Controls how one widget replaces another widget in the tree.

final, inherited

modifierKey → Key?

The actual key of the widget, which Modifier wrapped

final, inherited

mouseCursor → MouseCursor?

The cursor for a mouse pointer when it enters or is hovering over the widget.

final

onDoubleTap → GestureTapCallback?

Called when the user double taps this part of the material.

final

onFocusChange → ValueChanged<bool>?

Handler called when the focus changes.

final

onHighlightChanged → ValueChanged<bool>?

Called when this part of the material either becomes highlighted or stops being highlighted.

final

onHover → ValueChanged<bool>?

Called when a pointer enters or exits the ink response area.

final

onLongPress → GestureLongPressCallback?

Called when the user long-presses on this part of the material.

final

onTap → GestureTapCallback?

Called when the user taps this part of the material.

final

onTapCancel → GestureTapCallback?

Called when the user cancels a tap that was started on this part of the material.

final

onTapDown → GestureTapDownCallback?

Called when the user taps down this part of the material.

final

onTapUp → GestureTapUpCallback?

Called when the user releases a tap that was started on this part of the material. onTap is called immediately after.

final

overlayColor → MaterialStateProperty<Color?>?

Defines the ink response focus, hover, and splash colors.

final

radius → double?

The radius of the ink splash.

final

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

splashColor → Color?

The splash color of the ink response. If this property is null then the splash color of the theme, ThemeData.splashColor, will be used.

final

splashFactory → InteractiveInkFeatureFactory?

Defines the appearance of the splash.

final

statesController → MaterialStatesController?

Represents the interactive "state" of this widget in terms of a set of MaterialStates, like MaterialState.pressed and MaterialState.focused.

final

Methods

build(BuildContext context) → Widget

Describes the part of the user interface represented by this widget.

inherited

buildWithChild(BuildContext context, Widget? child) → Widget

A build method that receives an extra child parameter.

override

createElement() → SingleChildStatelessElement

Create a SingleChildStatelessElement

inherited

debugDescribeChildren() → List<DiagnosticsNode>

Returns a list of DiagnosticsNode objects describing this node's children.

inherited

debugFillProperties(DiagnosticPropertiesBuilder properties) → void

Add additional properties associated with the node.

inherited

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

toDiagnosticsNode({String? name, DiagnosticsTreeStyle? style}) → DiagnosticsNode

Returns a debug representation of the object that is used by debugging tools and by DiagnosticsNode.toStringDeep.

inherited

toString({DiagnosticLevel minLevel = DiagnosticLevel.info}) → String

A string representation of this object.

inherited

toStringDeep({String prefixLineOne = '', String? prefixOtherLines, DiagnosticLevel minLevel = DiagnosticLevel.debug}) → String

Returns a string representation of this node and its descendants.

inherited

toStringShallow({String joiner = ', ', DiagnosticLevel minLevel = DiagnosticLevel.debug}) → String

Returns a one-line detailed description of the object.

inherited

toStringShort() → String

A short, textual description of this widget.

inherited

Operators

operator ==(Object other) → bool

The equality operator.

inherited