govlab-styleguide
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A styleguide / lightweight frontend framework for GovLab websites
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JavaScript
/**
* DropdownMenu module.
* @module foundation.dropdown-menu
* @requires foundation.util.keyboard
* @requires foundation.util.box
* @requires foundation.util.nest
*/
!function($, Foundation){
'use strict';
/**
* Creates a new instance of DropdownMenu.
* @class
* @fires DropdownMenu#init
* @param {jQuery} element - jQuery object to make into a dropdown menu.
* @param {Object} options - Overrides to the default plugin settings.
*/
function DropdownMenu(element, options){
this.$element = element;
this.options = $.extend({}, DropdownMenu.defaults, this.$element.data(), options);
Foundation.Nest.Feather(this.$element, 'dropdown');
this._init();
Foundation.registerPlugin(this, 'DropdownMenu');
Foundation.Keyboard.register('DropdownMenu', {
'ENTER': 'open',
'SPACE': 'open',
'ARROW_RIGHT': 'next',
'ARROW_UP': 'up',
'ARROW_DOWN': 'down',
'ARROW_LEFT': 'previous',
'ESCAPE': 'close'
});
}
/**
* Default settings for plugin
*/
DropdownMenu.defaults = {
/**
* Disallows hover events from opening submenus
* @option
* @example false
*/
disableHover: false,
/**
* Allow a submenu to automatically close on a mouseleave event, if not clicked open.
* @option
* @example true
*/
autoclose: true,
/**
* Amount of time to delay opening a submenu on hover event.
* @option
* @example 50
*/
hoverDelay: 50,
/**
* Allow a submenu to open/remain open on parent click event. Allows cursor to move away from menu.
* @option
* @example true
*/
clickOpen: false,
/**
* Amount of time to delay closing a submenu on a mouseleave event.
* @option
* @example 500
*/
closingTime: 500,
/**
* Position of the menu relative to what direction the submenus should open. Handled by JS.
* @option
* @example 'left'
*/
alignment: 'left',
/**
* Allow clicks on the body to close any open submenus.
* @option
* @example true
*/
closeOnClick: true,
/**
* Class applied to vertical oriented menus, Foundation default is `vertical`. Update this if using your own class.
* @option
* @example 'vertical'
*/
verticalClass: 'vertical',
/**
* Class applied to right-side oriented menus, Foundation default is `align-right`. Update this if using your own class.
* @option
* @example 'align-right'
*/
rightClass: 'align-right',
/**
* Boolean to force overide the clicking of links to perform default action, on second touch event for mobile.
* @option
* @example false
*/
forceFollow: true
};
/**
* Initializes the plugin, and calls _prepareMenu
* @private
* @function
*/
DropdownMenu.prototype._init = function(){
var subs = this.$element.find('li.is-dropdown-submenu-parent');
this.$element.children('.is-dropdown-submenu-parent').children('.is-dropdown-submenu').addClass('first-sub');
this.$menuItems = this.$element.find('[role="menuitem"]');
this.$tabs = this.$element.children('[role="menuitem"]');
this.isVert = this.$element.hasClass(this.options.verticalClass);
this.$tabs.find('ul.is-dropdown-submenu').addClass(this.options.verticalClass);
if(this.$element.hasClass(this.options.rightClass) || this.options.alignment === 'right'){
this.options.alignment = 'right';
subs.addClass('is-left-arrow opens-left');
}else{
subs.addClass('is-right-arrow opens-right');
}
if(!this.isVert){
this.$tabs.filter('.is-dropdown-submenu-parent').removeClass('is-right-arrow is-left-arrow opens-right opens-left')
.addClass('is-down-arrow');
}
this.changed = false;
this._events();
};
/**
* Adds event listeners to elements within the menu
* @private
* @function
*/
DropdownMenu.prototype._events = function(){
var _this = this,
hasTouch = 'ontouchstart' in window || (typeof window.ontouchstart !== 'undefined'),
parClass = 'is-dropdown-submenu-parent',
delay;
if(this.options.clickOpen || hasTouch){
this.$menuItems.on('click.zf.dropdownmenu touchstart.zf.dropdownmenu', function(e){
var $elem = $(e.target).parentsUntil('ul', '.' + parClass),
hasSub = $elem.hasClass(parClass),
hasClicked = $elem.attr('data-is-click') === 'true',
$sub = $elem.children('.is-dropdown-submenu');
if(hasSub){
if(hasClicked){
if(!_this.options.closeOnClick || (!_this.options.clickOpen && !hasTouch) || (_this.options.forceFollow && hasTouch)){ return; }
else{
e.stopImmediatePropagation();
e.preventDefault();
_this._hide($elem);
}
}else{
e.preventDefault();
e.stopImmediatePropagation();
_this._show($elem.children('.is-dropdown-submenu'));
$elem.add($elem.parentsUntil(_this.$element, '.' + parClass)).attr('data-is-click', true);
}
}else{ return; }
});
}
if(!this.options.disableHover){
this.$menuItems.on('mouseenter.zf.dropdownmenu', function(e){
e.stopImmediatePropagation();
var $elem = $(this),
hasSub = $elem.hasClass(parClass);
if(hasSub){
clearTimeout(delay);
delay = setTimeout(function(){
_this._show($elem.children('.is-dropdown-submenu'));
}, _this.options.hoverDelay);
}
}).on('mouseleave.zf.dropdownmenu', function(e){
var $elem = $(this),
hasSub = $elem.hasClass(parClass);
if(hasSub && _this.options.autoclose){
if($elem.attr('data-is-click') === 'true' && _this.options.clickOpen){ return false; }
// clearTimeout(delay);
delay = setTimeout(function(){
_this._hide($elem);
}, _this.options.closingTime);
}
});
}
this.$menuItems.on('keydown.zf.dropdownmenu', function(e){
var $element = $(e.target).parentsUntil('ul', '[role="menuitem"]'),
isTab = _this.$tabs.index($element) > -1,
$elements = isTab ? _this.$tabs : $element.siblings('li').add($element),
$prevElement,
$nextElement;
$elements.each(function(i) {
if ($(this).is($element)) {
$prevElement = $elements.eq(i-1);
$nextElement = $elements.eq(i+1);
return;
}
});
var nextSibling = function() {
if (!$element.is(':last-child')) $nextElement.children('a:first').focus();
}, prevSibling = function() {
$prevElement.children('a:first').focus();
}, openSub = function() {
var $sub = $element.children('ul.is-dropdown-submenu');
if($sub.length){
_this._show($sub);
$element.find('li > a:first').focus();
}else{ return; }
}, closeSub = function() {
//if ($element.is(':first-child')) {
var close = $element.parent('ul').parent('li');
close.children('a:first').focus();
_this._hide(close);
//}
};
var functions = {
open: openSub,
close: function() {
_this._hide(_this.$element);
_this.$menuItems.find('a:first').focus(); // focus to first element
},
handled: function() {
e.preventDefault();
e.stopImmediatePropagation();
}
};
if (isTab) {
if (_this.vertical) { // vertical menu
if (_this.options.alignment === 'left') { // left aligned
$.extend(functions, {
down: nextSibling,
up: prevSibling,
next: openSub,
previous: closeSub
});
} else { // right aligned
$.extend(functions, {
down: nextSibling,
up: prevSibling,
next: closeSub,
previous: openSub
});
}
} else { // horizontal menu
$.extend(functions, {
next: nextSibling,
previous: prevSibling,
down: openSub,
up: closeSub
});
}
} else { // not tabs -> one sub
if (_this.options.alignment === 'left') { // left aligned
$.extend(functions, {
next: openSub,
previous: closeSub,
down: nextSibling,
up: prevSibling
});
} else { // right aligned
$.extend(functions, {
next: closeSub,
previous: openSub,
down: nextSibling,
up: prevSibling
});
}
}
Foundation.Keyboard.handleKey(e, 'DropdownMenu', functions);
});
};
/**
* Adds an event handler to the body to close any dropdowns on a click.
* @function
* @private
*/
DropdownMenu.prototype._addBodyHandler = function(){
var $body = $(document.body),
_this = this;
$body.off('mouseup.zf.dropdownmenu touchend.zf.dropdownmenu')
.on('mouseup.zf.dropdownmenu touchend.zf.dropdownmenu', function(e){
var $link = _this.$element.find(e.target);
if($link.length){ return; }
_this._hide();
$body.off('mouseup.zf.dropdownmenu touchend.zf.dropdownmenu');
});
};
/**
* Opens a dropdown pane, and checks for collisions first.
* @param {jQuery} $sub - ul element that is a submenu to show
* @function
* @private
* @fires DropdownMenu#show
*/
DropdownMenu.prototype._show = function($sub){
var idx = this.$tabs.index(this.$tabs.filter(function(i, el){
return $(el).find($sub).length > 0;
}));
var $sibs = $sub.parent('li.is-dropdown-submenu-parent').siblings('li.is-dropdown-submenu-parent');
this._hide($sibs, idx);
$sub.css('visibility', 'hidden').addClass('js-dropdown-active').attr({'aria-hidden': false})
.parent('li.is-dropdown-submenu-parent').addClass('is-active')
.attr({'aria-selected': true, 'aria-expanded': true});
var clear = Foundation.Box.ImNotTouchingYou($sub, null, true);
if(!clear){
var oldClass = this.options.alignment === 'left' ? '-right' : '-left',
$parentLi = $sub.parent('.is-dropdown-submenu-parent');
$parentLi.removeClass('opens' + oldClass).addClass('opens-' + this.options.alignment);
clear = Foundation.Box.ImNotTouchingYou($sub, null, true);
if(!clear){
$parentLi.removeClass('opens-' + this.options.alignment).addClass('opens-inner');
}
this.changed = true;
}
$sub.css('visibility', '');
if(this.options.closeOnClick){ this._addBodyHandler(); }
/**
* Fires when the new dropdown pane is visible.
* @event DropdownMenu#show
*/
this.$element.trigger('show.zf.dropdownmenu', [$sub]);
};
/**
* Hides a single, currently open dropdown pane, if passed a parameter, otherwise, hides everything.
* @function
* @param {jQuery} $elem - element with a submenu to hide
* @param {Number} idx - index of the $tabs collection to hide
* @private
*/
DropdownMenu.prototype._hide = function($elem, idx){
var $toClose;
if($elem && $elem.length){
$toClose = $elem;
}else if(idx !== undefined){
$toClose = this.$tabs.not(function(i, el){
return i === idx;
});
}
else{
$toClose = this.$element;
}
var somethingToClose = $toClose.hasClass('is-active') || $toClose.find('.is-active').length > 0;
if(somethingToClose){
$toClose.find('li.is-active').add($toClose).attr({
'aria-selected': false,
'aria-expanded': false,
'data-is-click': false
}).removeClass('is-active');
$toClose.find('ul.js-dropdown-active').attr({
'aria-hidden': true
}).removeClass('js-dropdown-active');
if(this.changed || $toClose.find('opens-inner').length){
var oldClass = this.options.alignment === 'left' ? 'right' : 'left';
$toClose.find('li.is-dropdown-submenu-parent').add($toClose)
.removeClass('opens-inner opens-' + this.options.alignment)
.addClass('opens-' + oldClass);
this.changed = false;
}
/**
* Fires when the open menus are closed.
* @event DropdownMenu#hide
*/
this.$element.trigger('hide.zf.dropdownmenu', [$toClose]);
}
};
/**
* Destroys the plugin.
* @function
*/
DropdownMenu.prototype.destroy = function(){
this.$menuItems.off('.zf.dropdownmenu').removeAttr('data-is-click')
.removeClass('is-right-arrow is-left-arrow is-down-arrow opens-right opens-left opens-inner');
Foundation.Nest.Burn(this.$element, 'dropdown');
Foundation.unregisterPlugin(this);
};
Foundation.plugin(DropdownMenu, 'DropdownMenu');
}(jQuery, window.Foundation);