InteractiveViewer class

A widget that enables pan and zoom interactions with its child.

The user can transform the child by dragging to pan or pinching to zoom.

By default, InteractiveViewer clips its child using Clip.hardEdge. To prevent this behavior, consider setting clipBehavior to Clip.none. When clipBehavior is Clip.none, InteractiveViewer may draw outside of its original area of the screen, such as when a child is zoomed in and increases in size. However, it will not receive gestures outside of its original area. To prevent dead areas where InteractiveViewer does not receive gestures, don't set clipBehavior or be sure that the InteractiveViewer widget is the size of the area that should be interactive.

Constructors

InteractiveViewer({Key? key, Clip clipBehavior = Clip.hardEdge, PanAxis panAxis = PanAxis.free, EdgeInsets boundaryMargin = EdgeInsets.zero, bool constrained = true, double maxScale = 2.5, double minScale = 0.8, double interactionEndFrictionCoefficient = _kDrag, GestureScaleEndCallback? onInteractionEnd, GestureScaleStartCallback? onInteractionStart, GestureScaleUpdateCallback? onInteractionUpdate, bool panEnabled = true, bool scaleEnabled = true, double scaleFactor = kDefaultMouseScrollToScaleFactor, TransformationController? transformationController, Alignment? alignment, bool trackpadScrollCausesScale = false, required Widget child}): Create an InteractiveViewer.
InteractiveViewer.builder({Key? key, Clip clipBehavior = Clip.hardEdge, PanAxis panAxis = PanAxis.free, EdgeInsets boundaryMargin = EdgeInsets.zero, double maxScale = 2.5, double minScale = 0.8, double interactionEndFrictionCoefficient = _kDrag, GestureScaleEndCallback? onInteractionEnd, GestureScaleStartCallback? onInteractionStart, GestureScaleUpdateCallback? onInteractionUpdate, bool panEnabled = true, bool scaleEnabled = true, double scaleFactor = 200.0, TransformationController? transformationController, Alignment? alignment, bool trackpadScrollCausesScale = false, required InteractiveViewerWidgetBuilder builder}): Creates an InteractiveViewer for a child that is created on demand.

Properties

alignment → Alignment?: The alignment of the child's origin, relative to the size of the box.
final
boundaryMargin → EdgeInsets: A margin for the visible boundaries of the child.
final
builder → InteractiveViewerWidgetBuilder?: Builds the child of this widget.
final
child → Widget?: The child Widget that is transformed by InteractiveViewer.
final
clipBehavior → Clip: If set to Clip.none, the child may extend beyond the size of the InteractiveViewer, but it will not receive gestures in these areas. Be sure that the InteractiveViewer is the desired size when using Clip.none.
final
constrained → bool: Whether the normal size constraints at this point in the widget tree are applied to the child.
final
hashCode → int: The hash code for this object.
no setterinherited
interactionEndFrictionCoefficient → double: Changes the deceleration behavior after a gesture.
final
key → Key?: Controls how one widget replaces another widget in the tree.
finalinherited
maxScale → double: The maximum allowed scale.
final
minScale → double: The minimum allowed scale.
final
onInteractionEnd → GestureScaleEndCallback?: Called when the user ends a pan or scale gesture on the widget.
final
onInteractionStart → GestureScaleStartCallback?: Called when the user begins a pan or scale gesture on the widget.
final
onInteractionUpdate → GestureScaleUpdateCallback?: Called when the user updates a pan or scale gesture on the widget.
final
panAxis → PanAxis: When set to PanAxis.aligned, panning is only allowed in the horizontal axis or the vertical axis, diagonal panning is not allowed.
final
panEnabled → bool: If false, the user will be prevented from panning.
final
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
scaleEnabled → bool: If false, the user will be prevented from scaling.
final
scaleFactor → double: Determines the amount of scale to be performed per pointer scroll.
final
trackpadScrollCausesScale → bool: Whether scrolling up/down on a trackpad should cause scaling instead of panning.
final
transformationController → TransformationController?: A TransformationController for the transformation performed on the child.
final

Methods

createElement() → StatefulElement: Creates a StatefulElement to manage this widget's location in the tree.
inherited
createState() → State<InteractiveViewer>: Creates the mutable state for this widget at a given location in the tree.
override
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, int wrapWidth = 65}) → 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

Static Methods

getAxisAlignedBoundingBox(Quad quad) → Quad: Given a quad, return its axis aligned bounding box.
getNearestPointInside(Vector3 point, Quad quad) → Vector3: Get the point inside (inclusively) the given Quad that is nearest to the given Vector3.
getNearestPointOnLine(Vector3 point, Vector3 l1, Vector3 l2) → Vector3: Returns the closest point to the given point on the given line segment.
pointIsInside(Vector3 point, Quad quad) → bool: Returns true iff the point is inside the rectangle given by the Quad, inclusively. Algorithm from https://math.stackexchange.com/a/190373.