PressListener (direct usage)

PressListener (from scenerystack/scenery) is the shared base class documented alongside its most common subclass in PressListener and FireListener — that page covers the options and read-only Properties both classes share. This page is for the case PressListener and FireListener calls out explicitly: reaching for PressListener directly, without FireListener's fire-on-release semantics or DragListener's coordinate tracking, because the interaction is something else — a press-and-hold tool, a custom multi-pointer gesture, or a Node whose "pressed" visual state needs to track PDOM (keyboard/switch-device) focus as well as pointer input.

import { Node, Circle, PressListener } from 'scenerystack/scenery';
import { Tandem } from 'scenerystack/tandem';

const magnifier = new Node( { children: [ new Circle( 20, { fill: 'lightblue' } ) ], cursor: 'pointer' } );

const magnifyListener = new PressListener( {
  press: () => magnifier.setScaleMagnitude( 1.5 ),
  release: () => magnifier.setScaleMagnitude( 1 ),
  canStartPress: () => !magnifier.isDisposed,
  tandem: Tandem.OPT_OUT
} );

magnifier.addInputListener( magnifyListener );

// Drive a highlight off state that also accounts for keyboard focus, not just pointer hover:
magnifyListener.isOverOrFocusedProperty.link( overOrFocused => {
  magnifier.opacity = overOrFocused ? 1 : 0.8;
});

PressListener extends axon's EnabledComponent, so every instance also has a standard enabledProperty/enabled — disabling the listener prevents new presses from starting without needing a separate guard in canStartPress.

PDOM- and focus-aware state

Beyond the isPressedProperty/isOverProperty/isHoveringProperty/isHighlightedProperty covered in PressListener and FireListener, PressListener tracks additional state specifically so a Node's "looks interactive" visuals stay correct for keyboard and switch-device users, not just mouse/touch:

Property	Meaning
isFocusedProperty	Whether this listener's Node currently has PDOM focus
isOverOrFocusedProperty	isOverProperty || (focused and the Display is currently showing focus highlights) — the right signal for "should this look highlighted," including keyboard users
pdomClickingProperty	true while a press is being processed from a PDOM click event (as opposed to real pointer down/up) — needed because some assistive devices send a single click rather than separate down/up
looksPressedProperty	pdomClickingProperty || isPressedProperty — whether the button should render as pressed, accounting for the fact that a PDOM click fires the press/release callbacks immediately but should still look pressed briefly
overPointers	An ObservableArray<Pointer> of every pointer currently over the listener's Node

a11yLooksPressedInterval (default 100 ms) controls how long looksPressedProperty stays true after a PDOM click, since the press and release callbacks both fire essentially at once for that input source.

Methods beyond press/release/drag

Method	Effect
canPress( event )	Whether a press could currently start for the given event (checks button/attachment/canStartPress)
canClick()	Whether a programmatic click() could currently succeed
click( event, callback? )	Simulates a full press-then-release from a single PDOM click event; used internally by FireListener and accessible-input handling
focus( event ) / blur()	Called by scenery's focus system to update isFocusedProperty; not something you typically call directly
step()	Advances any pending collapsed drag event (see collapseDragEvents); called automatically if the listener is registered appropriately
setCreatePanTargetBounds( fn )	Supplies a callback returning the Bounds2 that AnimatedPanZoomListener should keep in view while this listener is pressed — useful when the pressed/dragged region differs from the listener's Node bounds

useInputListenerCursor

useInputListenerCursor: true makes any Node this listener is attached to adopt pressCursor as its effective cursor whenever that Node's own cursor is null — a small convenience so you don't have to set cursor: 'pointer' on the Node separately from configuring the listener's pressCursor.

Reach for PressListener directly when the interaction isn't "fire" or "drag"

If the shape of the interaction is genuinely custom — press-and-hold-to-charge, multi-touch gesture recognition, or anything that needs isOverOrFocusedProperty/overPointers — build on PressListener directly rather than working around FireListener's fire semantics or DragListener's coordinate machinery. Both of those subclasses exist specifically to save you from reimplementing this state for the two most common cases.

tandem still defaults to required

Like FireListener and DragListener, a directly-constructed PressListener defaults tandem to Tandem.REQUIRED and defaults phetioReadOnly: true on its internal press/release PhetioActions. Pass Tandem.OPT_OUT for non-instrumented sim code, as shown above.