PaintObserver¶

Overview¶

Hooks up listeners to a paint (fill or stroke) to determine when its represented value has changed.

@author Jonathan Olson <jonathan.olson@colorado.edu>

Class PaintObserver¶

import { PaintObserver } from 'scenerystack/scenery';

Constructor¶

new PaintObserver( changeCallback )¶

Instance Methods¶

clean()¶

Releases references without sending the notifications. @public

updateSecondary( newPaint, oldPaint, property )¶

Called when the value of a "primary" Property (contents of one, main or as a Gradient) is potentially changed. @private

@param {string|Color} newPaint @param {string|Color} oldPaint @param {Property} property

attachPrimary( paint )¶

Attempt to attach listeners to the paint's primary (the paint itself), or something else that acts like the primary (properties on a gradient). @private

TODO: Note that this is called for gradient colors also https://github.com/phetsims/scenery/issues/1581

NOTE: If it's a Property, we'll also need to handle the secondary (part inside the Property).

@param {PaintDef} paint

detachPrimary( paint )¶

Attempt to detach listeners from the paint's primary (the paint itself). @private

TODO: Note that this is called for gradient colors also https://github.com/phetsims/scenery/issues/1581

NOTE: If it's a Property or Gradient, we'll also need to handle the secondaries (part(s) inside the Property(ies)).

@param {PaintDef} paint

attachSecondary( paint )¶

Attempt to attach listeners to the paint's secondary (part within the Property). @private

@param {string|Color} paint

notifyChanged()¶

Calls the change callback, and invalidates the paint itself if it's a gradient. @private

secondaryLazyLinkProperty( property )¶

Adds our secondary listener to the Property (unless there is already one, in which case we record the counts). @private

@param {Property.<*>} property

secondaryUnlinkProperty( property )¶

Removes our secondary listener from the Property (unless there were more than 1 time we needed to listen to it, in which case we reduce the count). @private

@param {Property.<*>} property

Source Code¶

See the source for PaintObserver.js in the scenery repository.