update hotkeys when list of input listeners changes, see #1621

js/input/hotkeyManager.ts

@@ -23,7 +23,7 @@
  * @author Jonathan Olson <[email protected]>
  */
 
-import { EnglishKey, eventCodeToEnglishString, FocusManager, globalHotkeyRegistry, globalKeyStateTracker, Hotkey, KeyboardUtils, metaEnglishKeys, scenery } from '../imports.js';
+import { EnglishKey, eventCodeToEnglishString, FocusManager, globalHotkeyRegistry, globalKeyStateTracker, Hotkey, KeyboardUtils, metaEnglishKeys, Node, scenery } from '../imports.js';
 import DerivedProperty, { UnknownDerivedProperty } from '../../../axon/js/DerivedProperty.js';
 import TProperty from '../../../axon/js/TProperty.js';
 import TinyProperty from '../../../axon/js/TinyProperty.js';
@@ -213,6 +213,22 @@ class HotkeyManager {
     } );
   }
 
+  /**
+   * Scenery-internal. If a Node along the focused trail changes its input listeners we need to manually recompute
+   * the available hotkeys. There is no other way at this time to observe the input listeners of a Node. Otherwise,
+   * the available hotkeys will be recomputed when focus changes, inputEnabledProperty changes for Nodes along the
+   * trail, or when global hotkeys change.
+   *
+   * Called by Node.addInputListener/Node.removeInputListener.
+   *
+   * (scenery-internal)
+   */
+  public updateHotkeysFromInputListenerChange( node: Node ): void {
+    if ( FocusManager.pdomFocusProperty.value && FocusManager.pdomFocusProperty.value.trail.nodes.includes( node ) ) {
+      this.availableHotkeysProperty.recomputeDerivation();
+    }
+  }
+
   /**
    * Given a main `key`, see if there is a hotkey that should be considered "active/pressed" for it.
    *

js/listeners/KeyboardListenerTests.ts

@@ -109,12 +109,6 @@ QUnit.test( 'KeyboardListener Tests', assert => {
 
   a.addInputListener( listenerWithOverlappingKeys );
 
-  // TODO: https://github.com/phetsims/scenery/issues/1570, This is a workaround for a problem with hotkeyManager
-  //   where it doesn't update the availableHotkeys when new input listeners are added. We can manually update by
-  //   triggering focus changes.
-  a.blur();
-  a.focus();
-
   triggerKeydownEvent( domElementA, KeyboardUtils.KEY_P, true );
   assert.ok( !pFired, 'p should not fire because control key is down' );
   assert.ok( ctrlPFired, 'ctrl P should have fired' );

js/nodes/Node.ts

@@ -170,7 +170,7 @@ import Tandem from '../../../tandem/js/Tandem.js';
 import BooleanIO from '../../../tandem/js/types/BooleanIO.js';
 import IOType from '../../../tandem/js/types/IOType.js';
 import TProperty from '../../../axon/js/TProperty.js';
-import { ACCESSIBILITY_OPTION_KEYS, CanvasContextWrapper, CanvasSelfDrawable, Display, DOMSelfDrawable, Drawable, Features, Filter, Image, ImageOptions, Instance, isHeightSizable, isWidthSizable, LayoutConstraint, Mouse, ParallelDOM, ParallelDOMOptions, Picker, Pointer, Renderer, RendererSummary, scenery, serializeConnectedNodes, SVGSelfDrawable, TInputListener, TLayoutOptions, Trail, WebGLSelfDrawable } from '../imports.js';
+import { ACCESSIBILITY_OPTION_KEYS, CanvasContextWrapper, CanvasSelfDrawable, Display, DOMSelfDrawable, Drawable, Features, Filter, hotkeyManager, Image, ImageOptions, Instance, isHeightSizable, isWidthSizable, LayoutConstraint, Mouse, ParallelDOM, ParallelDOMOptions, Picker, Pointer, Renderer, RendererSummary, scenery, serializeConnectedNodes, SVGSelfDrawable, TInputListener, TLayoutOptions, Trail, WebGLSelfDrawable } from '../imports.js';
 import optionize, { combineOptions, EmptySelfOptions, optionize3 } from '../../../phet-core/js/optionize.js';
 import IntentionalAny from '../../../phet-core/js/types/IntentionalAny.js';
 import Utils from '../../../dot/js/Utils.js';
@@ -2333,6 +2333,12 @@ class Node extends ParallelDOM {
       this._inputListeners.push( listener );
       this._picker.onAddInputListener();
       if ( assertSlow ) { this._picker.audit(); }
+
+      // If the listener contains hotkeys, active hotkeys may need to be updated. There is no event
+      // for changing input listeners. See hotkeyManager for more information.
+      if ( listener.hotkeys ) {
+        hotkeyManager.updateHotkeysFromInputListenerChange( this );
+      }
     }
     return this;
   }
@@ -2349,6 +2355,12 @@ class Node extends ParallelDOM {
       this._inputListeners.splice( index, 1 );
       this._picker.onRemoveInputListener();
       if ( assertSlow ) { this._picker.audit(); }
+
+      // If the listener contains hotkeys, active hotkeys may need to be updated. There is no event
+      // for changing input listeners. See hotkeyManager for more information.
+      if ( listener.hotkeys ) {
+        hotkeyManager.updateHotkeysFromInputListenerChange( this );
+      }
     }
 
     return this;