open-consul/ui-v2/app/components/aria-menu.js

152 lines
4.6 KiB
JavaScript

import Component from '@ember/component';
import { inject as service } from '@ember/service';
import { set } from '@ember/object';
import { next } from '@ember/runloop';
const TAB = 9;
const ENTER = 13;
const ESC = 27;
const SPACE = 32;
const END = 35;
const HOME = 36;
const ARROW_UP = 38;
const ARROW_DOWN = 40;
const keys = {
vertical: {
[ARROW_DOWN]: function($items, i = -1) {
return (i + 1) % $items.length;
},
[ARROW_UP]: function($items, i = 0) {
if (i === 0) {
return $items.length - 1;
} else {
return i - 1;
}
},
[HOME]: function($items, i) {
return 0;
},
[END]: function($items, i) {
return $items.length - 1;
},
},
horizontal: {},
};
const COMPONENT_ID = 'component-aria-menu-';
// ^menuitem supports menuitemradio and menuitemcheckbox
const MENU_ITEMS = '[role^="menuitem"]';
export default Component.extend({
tagName: '',
dom: service('dom'),
router: service('router'),
guid: '',
expanded: false,
orientation: 'vertical',
keyboardAccess: true,
init: function() {
this._super(...arguments);
set(this, 'guid', this.dom.guid(this));
this._listeners = this.dom.listeners();
this._routelisteners = this.dom.listeners();
},
didInsertElement: function() {
// TODO: How do you detect whether the children have changed?
// For now we know that these elements exist and never change
this.$menu = this.dom.element(`#${COMPONENT_ID}menu-${this.guid}`);
const labelledBy = this.$menu.getAttribute('aria-labelledby');
this.$trigger = this.dom.element(`#${labelledBy}`);
this._routelisteners.add(this.router, {
routeWillChange: () => this.actions.close.apply(this, [{}]),
});
},
willDestroyElement: function() {
this._super(...arguments);
this._listeners.remove();
this._routelisteners.remove();
},
actions: {
keypressClick: function(e) {
e.target.dispatchEvent(new MouseEvent('click'));
},
keypress: function(e) {
// If the event is from the trigger and its not an opening/closing
// key then don't do anything
if (![ENTER, SPACE, ARROW_UP, ARROW_DOWN].includes(e.keyCode)) {
return;
}
e.stopPropagation();
// Also we may do this but not need it if we return early below
// although once we add support for [A-Za-z] it unlikely we won't use
// the keypress
// TODO: We need to use > somehow here so we don't select submenus
const $items = [...this.dom.elements(MENU_ITEMS, this.$menu)];
if (!this.expanded) {
this.$trigger.dispatchEvent(new MouseEvent('click'));
if (e.keyCode === ENTER || e.keyCode === SPACE) {
$items[0].focus();
return;
}
}
// this will prevent anything happening if you haven't pushed a
// configurable key
if (typeof keys[this.orientation][e.keyCode] === 'undefined') {
return;
}
// prevent any scroll, or default actions
e.preventDefault();
const $focused = this.dom.element(`${MENU_ITEMS}:focus`, this.$menu);
let i;
if ($focused) {
i = $items.findIndex(function($item) {
return $item === $focused;
});
}
const $next = $items[keys[this.orientation][e.keyCode]($items, i)];
$next.focus();
},
// TODO: The argument here needs to change to an event
// see toggle-button.change
change: function(e) {
const open = e.target.checked;
if (open) {
this.actions.open.apply(this, [e]);
} else {
this.actions.close.apply(this, [e]);
}
},
close: function(e) {
this._listeners.remove();
set(this, 'expanded', false);
// TODO: Find a better way to do this without using next
// This is needed so when you press shift tab to leave the menu
// and go to the previous button, it doesn't focus the trigger for
// the menu itself
next(() => {
this.$trigger.removeAttribute('tabindex');
});
},
open: function(e) {
set(this, 'expanded', true);
// Take the trigger out of the tabbing whilst the menu is open
this.$trigger.setAttribute('tabindex', '-1');
this._listeners.add(this.dom.document(), {
keydown: e => {
// Keep focus on the trigger when you close via ESC
if (e.keyCode === ESC) {
this.$trigger.focus();
}
if (e.keyCode === TAB || e.keyCode === ESC) {
this.$trigger.dispatchEvent(new MouseEvent('click'));
return;
}
if (!this.keyboardAccess) {
return;
}
this.actions.keypress.apply(this, [e]);
},
});
},
},
});