app/assets/javascripts/components/dropdown.js
jQuery.easing['jswing'] = jQuery.easing['swing'];
jQuery.extend(jQuery.easing,
{
def: 'easeOutQuad',
swing: function (x, t, b, c, d) {
return jQuery.easing[jQuery.easing.def](x, t, b, c, d);
},
easeOutQuad: function (x, t, b, c, d) {
return -c * (t /= d) * (t - 2) + b;
},
easeOutCubic: function (x, t, b, c, d) {
return c * ((t = t / d - 1) * t * t + 1) + b;
},
easeOutSine: function (x, t, b, c, d) {
return c * Math.sin(t / d * (Math.PI / 2)) + b;
}
});
(function ($) {
$.fn.scrollTo = function (elem) {
$(this).scrollTop($(this).scrollTop() - $(this).offset().top + $(elem).offset().top);
return this;
};
$.fn.dropdown = function (options) {
var defaults = {
inDuration: 300,
outDuration: 225,
constrain_width: false, // Does not change width of dropdown to that of the activator
hover: false, // Activate on hover
gutter: 0, // Spacing from edge
belowOrigin: false, // Displays dropdown below the button
alignment: 'right', // Displays dropdown with edge aligned to the left of button
stopPropagation: false
};
// Open dropdown.
if (options === 'open') {
this.each(function () {
$(this).trigger('open');
});
return false;
}
// Close dropdown.
if (options === 'close') {
this.each(function () {
$(this).trigger('close');
});
return false;
}
this.each(function () {
var origin = $(this);
var curr_options = $.extend({}, defaults, options);
var isFocused = false;
// Dropdown menu
var activates = $('#' + origin.attr('data-activates'));
function updateOptions() {
if (origin.data('induration') !== undefined)
curr_options.inDuration = origin.data('induration');
if (origin.data('outduration') !== undefined)
curr_options.outDuration = origin.data('outduration');
if (origin.data('constrainwidth') !== undefined)
curr_options.constrain_width = origin.data('constrainwidth');
if (origin.data('hover') !== undefined)
curr_options.hover = origin.data('hover');
if (origin.data('gutter') !== undefined)
curr_options.gutter = origin.data('gutter');
if (origin.data('beloworigin') !== undefined)
curr_options.belowOrigin = origin.data('beloworigin');
if (origin.data('alignment') !== undefined)
curr_options.alignment = origin.data('alignment');
if (origin.data('stoppropagation') !== undefined)
curr_options.stopPropagation = origin.data('stoppropagation');
}
updateOptions();
// Attach dropdown to its activator
origin.after(activates);
/*
Helper function to position and resize dropdown.
Used in hover and click handler.
*/
function placeDropdown(eventType) {
// Check for simultaneous focus and click events.
if (eventType === 'focus') {
isFocused = true;
}
// Check html data attributes
updateOptions();
// Set Dropdown state
activates.addClass('active');
origin.addClass('active');
// Constrain width
if (curr_options.constrain_width === true) {
activates.css('width', origin.outerWidth());
} else {
activates.css('white-space', 'nowrap');
}
// Offscreen detection
var windowHeight = window.innerHeight;
var originHeight = origin.innerHeight();
var offsetLeft = origin.offset().left;
var offsetTop = origin.offset().top - $(window).scrollTop();
var currAlignment = curr_options.alignment;
var gutterSpacing = 0;
var leftPosition = 0;
// Below Origin
var verticalOffset = 0;
if (curr_options.belowOrigin === true) {
verticalOffset = originHeight;
}
// Check for scrolling positioned container.
var scrollYOffset = 0;
var scrollXOffset = 0;
var wrapper = origin.parent();
if (!wrapper.is('body')) {
if (wrapper[0].scrollHeight > wrapper[0].clientHeight) {
scrollYOffset = wrapper[0].scrollTop;
}
if (wrapper[0].scrollWidth > wrapper[0].clientWidth) {
scrollXOffset = wrapper[0].scrollLeft;
}
}
if (offsetLeft + activates.innerWidth() > $(window).width()) {
// Dropdown goes past screen on right, force right alignment
currAlignment = 'right';
} else if (offsetLeft - activates.innerWidth() + origin.innerWidth() < 0) {
// Dropdown goes past screen on left, force left alignment
currAlignment = 'left';
}
// Vertical bottom offscreen detection
if (offsetTop + activates.innerHeight() > windowHeight) {
// If going upwards still goes offscreen, just crop height of dropdown.
if (offsetTop + originHeight - activates.innerHeight() < 0) {
var adjustedHeight = windowHeight - offsetTop - verticalOffset;
activates.css('max-height', adjustedHeight);
} else {
// Flow upwards.
if (!verticalOffset) {
verticalOffset += originHeight;
}
verticalOffset -= activates.innerHeight();
}
}
// Handle edge alignment
if (currAlignment === 'left') {
gutterSpacing = curr_options.gutter;
leftPosition = origin.position().left + gutterSpacing;
}
else if (currAlignment === 'right') {
var offsetRight = origin.position().left + origin.outerWidth() - activates.outerWidth();
gutterSpacing = -curr_options.gutter;
leftPosition = offsetRight + gutterSpacing;
}
// Position dropdown
activates.css({
position: 'absolute',
top: origin.position().top + verticalOffset + scrollYOffset,
left: leftPosition + scrollXOffset
});
// Show dropdown
activates.stop(true, true).css('opacity', 0)
.slideDown({
queue: false,
duration: curr_options.inDuration,
easing: 'easeOutCubic',
complete: function () {
$(this).css('height', '');
}
})
.animate({opacity: 1}, {queue: false, duration: curr_options.inDuration, easing: 'easeOutSine'});
}
function hideDropdown() {
// Check for simultaneous focus and click events.
isFocused = false;
activates.fadeOut(curr_options.outDuration);
activates.removeClass('active');
origin.removeClass('active');
setTimeout(function () {
activates.css('max-height', '');
}, curr_options.outDuration);
}
// Hover
if (curr_options.hover) {
var open = false;
origin.unbind('click.' + origin.attr('id'));
// Hover handler to show dropdown
origin.on('mouseenter', function () { // Mouse over
if (open === false) {
placeDropdown();
open = true;
}
});
origin.on('mouseleave', function (e) {
// If hover on origin then to something other than dropdown content, then close
var toEl = e.toElement || e.relatedTarget; // added browser compatibility for target element
if (!$(toEl).closest('.dropdown-content').is(activates)) {
activates.stop(true, true);
hideDropdown();
open = false;
}
});
activates.on('mouseleave', function (e) { // Mouse out
var toEl = e.toElement || e.relatedTarget;
if (!$(toEl).closest('.dropdown-button').is(origin)) {
activates.stop(true, true);
hideDropdown();
open = false;
}
});
// Click
} else {
// Click handler to show dropdown
origin.unbind('click.' + origin.attr('id'));
origin.bind('click.' + origin.attr('id'), function (e) {
if (!isFocused) {
if (origin[0] == e.currentTarget && !origin.hasClass('active') &&
($(e.target).closest('.dropdown-content').length === 0)) {
e.preventDefault(); // Prevents button click from moving window
if (curr_options.stopPropagation) {
e.stopPropagation();
}
placeDropdown('click');
}
// If origin is clicked and menu is open, close menu
else if (origin.hasClass('active')) {
hideDropdown();
$(document).unbind('click.' + activates.attr('id') + ' touchstart.' + activates.attr('id'));
}
// If menu open, add click close handler to document
if (activates.hasClass('active')) {
$(document).bind('click.' + activates.attr('id') + ' touchstart.' + activates.attr('id'), function (e) {
if (!activates.is(e.target) && !origin.is(e.target) && (!origin.find(e.target).length)) {
hideDropdown();
$(document).unbind('click.' + activates.attr('id') + ' touchstart.' + activates.attr('id'));
}
});
}
}
});
} // End else
// Listen to open and close event - useful for select component
origin.on('open', function (e, eventType) {
placeDropdown(eventType);
});
origin.on('close', hideDropdown);
});
}; // End dropdown plugin
$(document).ready(function () {
$('.dropdown-button').dropdown();
});
}(jQuery));