refactor(HXMenuElement): use Positionable mixin

docs/elements/hx-menu/index.html

@@ -35,6 +35,7 @@
           <ul class="hxList">
             <li><code>close</code></li>
             <li><code>open</code></li>
+            <li><code>reposition</code></li>
           </ul>
         </dd>
       </div>
@@ -44,10 +45,10 @@
 
 {% block attributes %}
   <dl>
-    <dt>open</dt>
+    <dt>open <i>(optional)</i></dt>
     <dd>Opens the menu</dd>
 
-    <dt>position</dt>
+    <dt>position <i>(optional)</i></dt>
     <dd>Positions the menu</dd>
 
     <dt>relative-to <i>(optional)</i></dt>

src/helix-ui/elements/HXMenuElement.js

@@ -1,193 +1,33 @@
 import { HXElement } from './HXElement';
-import { getPosition } from '../utils/position';
-import debounce from 'lodash/debounce';
 
-const DEFAULT_POSITION = 'bottom-start';
+import { mix } from '../utils';
+import { Positionable } from '../mixins/Positionable';
 
-/**
- * Fires when the element is concealed.
- *
- * @event Menu:close
- * @since 0.6.0
- * @type {CustomEvent}
- */
-
-/**
- * Fires when the element is revealed.
- *
- * @event Menu:open
- * @since 0.6.0
- * @type {CustomEvent}
- */
+class _ProtoClass extends mix(HXElement, Positionable) {}
 
 /**
  * Defines behavior for the `<hx-menu>` element.
  *
- * @emits Menu:close
- * @emits Menu:open
  * @extends HXElement
+ * @extends Positionable
  * @hideconstructor
  * @since 0.2.0
  */
-export class HXMenuElement extends HXElement {
+export class HXMenuElement extends _ProtoClass {
     static get is () {
         return 'hx-menu';
     }
 
+    /** @override */
     $onCreate () {
-        this._onDocumentClick = this._onDocumentClick.bind(this);
-        this._onDocumentScroll = this._onDocumentScroll.bind(this);
-        this._reposition = this._reposition.bind(this);
-
-        this._onWindowResize = debounce(this._reposition, 50);
+        super.$onCreate();
+        this.DEFAULT_POSITION = 'bottom-start';
     }
 
+    /** @override */
     $onConnect () {
-        this.$upgradeProperty('open');
-        this.$upgradeProperty('position');
-        this.$upgradeProperty('relativeTo');
-
-        this.$defaultAttribute('position', DEFAULT_POSITION);
+        super.$onConnect();
         this.$defaultAttribute('role', 'menu');
-
-        this.setAttribute('aria-hidden', !this.open);
         this.setAttribute('aria-expanded', this.open);
     }
-
-    static get $observedAttributes () {
-        return [ 'open' ];
-    }
-
-    $onAttributeChange (attr, oldVal, newVal) {
-        if (attr === 'open') {
-            this._attrOpenChange(oldVal, newVal);
-        }
-    }
-
-    /**
-     * External element that controls menu visibility.
-     * This is commonly a `<hx-disclosure>`.
-     *
-     * @readonly
-     * @type {HTMLElement}
-     */
-    get controlElement () {
-        return this.getRootNode().querySelector(`[aria-controls="${this.id}"]`);
-    }
-
-    /**
-     * Determines if the menu is revealed.
-     *
-     * @default false
-     * @type {Boolean}
-     */
-    get open () {
-        return this.hasAttribute('open');
-    }
-    set open (value) {
-        if (value) {
-            this.setAttribute('open', '');
-        } else {
-            this.removeAttribute('open');
-        }
-    }
-
-    // TODO: Need to re-evaluate how we handle positioning when scrolling
-    /**
-     * Where to position the open menu in relation to its reference element.
-     *
-     * @default 'bottom-start'
-     * @type {PositionString}
-     */
-    get position () {
-        return this.getAttribute('position') || DEFAULT_POSITION;
-    }
-    set position (value) {
-        this.setAttribute('position', value);
-    }
-
-    /**
-     * Reference element used to calculate open menu position.
-     *
-     * @readonly
-     * @type {HTMLElement}
-     */
-    get relativeElement () {
-        if (this.relativeTo) {
-            return this.getRootNode().getElementById(this.relativeTo);
-        } else {
-            return this.controlElement;
-        }
-    }
-
-    /**
-     * ID of the element to position the menu.
-     *
-     * @type {String}
-     */
-    get relativeTo () {
-        return this.getAttribute('relative-to');
-    }
-    set relativeTo (value) {
-        this.setAttribute('relative-to', value);
-    }
-
-    /** @private */
-    _addOpenListeners () {
-        document.addEventListener('click', this._onDocumentClick);
-        document.addEventListener('scroll', this._onDocumentScroll);
-        window.addEventListener('resize', this._onWindowResize);
-    }
-
-    /** @private */
-    _attrOpenChange (oldVal, newVal) {
-        let isOpen = (newVal !== null);
-        this.setAttribute('aria-hidden', !isOpen);
-        this.setAttribute('aria-expanded', isOpen);
-        this.$emit(isOpen ? 'open' : 'close');
-
-        if (isOpen) {
-            this._addOpenListeners();
-            this._reposition();
-        } else {
-            this._removeOpenListeners();
-        }
-    }
-
-    /** @private */
-    _onDocumentClick (evt) {
-        let isDescendant = this.contains(evt.target);
-        let withinControl = this.controlElement.contains(evt.target);
-        let isBackground = (!isDescendant && !withinControl);
-
-        if (this.open && isBackground) {
-            this.open = false;
-        }
-    }
-
-    /** @private */
-    _onDocumentScroll () {
-        this._reposition();
-    }
-
-    /** @private */
-    _removeOpenListeners () {
-        document.removeEventListener('click', this._onDocumentClick);
-        document.removeEventListener('scroll', this._onDocumentScroll);
-        window.removeEventListener('resize', this._onWindowResize);
-    }
-
-    /** @private */
-    _reposition () {
-        if (this.relativeElement) {
-            let { x, y } = getPosition({
-                element: this,
-                reference: this.relativeElement,
-                position: this.position,
-            });
-
-            this.style.top = `${y}px`;
-            this.style.left = `${x}px`;
-        }
-    }
 }