SortableJS- 簡單好用的網頁元素拖曳(drag and drop)及排序(sort)套件

SortableJS 是一個簡單好用的網頁元素拖曳(drag and drop)及排序(sort)套件，使用方式如下：

你可以透過 npm

$ npm install sortablejs --save

或 bower 讀入

$ bower install --save sortablejs

接著 import

// Default SortableJS
import Sortable from 'sortablejs';

// Core SortableJS (without default plugins)
import Sortable from 'sortablejs/modular/sortable.core.esm.js';

// Complete SortableJS (with all plugins)
import Sortable from 'sortablejs/modular/sortable.complete.esm.js';

也可使用 cdn：

<script src="https://cdn.jsdelivr.net/npm/sortablejs@latest/Sortable.min.js"></script>

接著準備以下 html

<ul id="items">
	<li>item 1</li>
	<li>item 2</li>
	<li>item 3</li>
</ul>

再套上 plugin 即可：

var el = document.getElementById('items');
var sortable = Sortable.create(el, { /* option */ });

option 裡面可以設定的內容可以參考官網說明自己設定。

var sortable = new Sortable(el, {
	group: "name",  // or { name: "...", pull: [true, false, 'clone', array], put: [true, false, array] }
	sort: true,  // sorting inside list
	delay: 0, // time in milliseconds to define when the sorting should start
	delayOnTouchOnly: false, // only delay if user is using touch
	touchStartThreshold: 0, // px, how many pixels the point should move before cancelling a delayed drag event
	disabled: false, // Disables the sortable if set to true.
	store: null,  // @see Store
	animation: 150,  // ms, animation speed moving items when sorting, `0` — without animation
	easing: "cubic-bezier(1, 0, 0, 1)", // Easing for animation. Defaults to null. See https://easings.net/ for examples.
	handle: ".my-handle",  // Drag handle selector within list items
	filter: ".ignore-elements",  // Selectors that do not lead to dragging (String or Function)
	preventOnFilter: true, // Call `event.preventDefault()` when triggered `filter`
	draggable: ".item",  // Specifies which items inside the element should be draggable

	dataIdAttr: 'data-id', // HTML attribute that is used by the `toArray()` method

	ghostClass: "sortable-ghost",  // Class name for the drop placeholder
	chosenClass: "sortable-chosen",  // Class name for the chosen item
	dragClass: "sortable-drag",  // Class name for the dragging item

	swapThreshold: 1, // Threshold of the swap zone
	invertSwap: false, // Will always use inverted swap zone if set to true
	invertedSwapThreshold: 1, // Threshold of the inverted swap zone (will be set to swapThreshold value by default)
	direction: 'horizontal', // Direction of Sortable (will be detected automatically if not given)

	forceFallback: false,  // ignore the HTML5 DnD behaviour and force the fallback to kick in

	fallbackClass: "sortable-fallback",  // Class name for the cloned DOM Element when using forceFallback
	fallbackOnBody: false,  // Appends the cloned DOM Element into the Document's Body
	fallbackTolerance: 0, // Specify in pixels how far the mouse should move before it's considered as a drag.

	dragoverBubble: false,
	removeCloneOnHide: true, // Remove the clone element when it is not showing, rather than just hiding it
	emptyInsertThreshold: 5, // px, distance mouse must be from empty sortable to insert drag element into it


	setData: function (/** DataTransfer */dataTransfer, /** HTMLElement*/dragEl) {
		dataTransfer.setData('Text', dragEl.textContent); // `dataTransfer` object of HTML5 DragEvent
	},

	// Element is chosen
	onChoose: function (/**Event*/evt) {
		evt.oldIndex;  // element index within parent
	},

	// Element is unchosen
	onUnchoose: function(/**Event*/evt) {
		// same properties as onEnd
	},

	// Element dragging started
	onStart: function (/**Event*/evt) {
		evt.oldIndex;  // element index within parent
	},

	// Element dragging ended
	onEnd: function (/**Event*/evt) {
		var itemEl = evt.item;  // dragged HTMLElement
		evt.to;    // target list
		evt.from;  // previous list
		evt.oldIndex;  // element's old index within old parent
		evt.newIndex;  // element's new index within new parent
		evt.oldDraggableIndex; // element's old index within old parent, only counting draggable elements
		evt.newDraggableIndex; // element's new index within new parent, only counting draggable elements
		evt.clone // the clone element
		evt.pullMode;  // when item is in another sortable: `"clone"` if cloning, `true` if moving
	},

	// Element is dropped into the list from another list
	onAdd: function (/**Event*/evt) {
		// same properties as onEnd
	},

	// Changed sorting within list
	onUpdate: function (/**Event*/evt) {
		// same properties as onEnd
	},

	// Called by any change to the list (add / update / remove)
	onSort: function (/**Event*/evt) {
		// same properties as onEnd
	},

	// Element is removed from the list into another list
	onRemove: function (/**Event*/evt) {
		// same properties as onEnd
	},

	// Attempt to drag a filtered element
	onFilter: function (/**Event*/evt) {
		var itemEl = evt.item;  // HTMLElement receiving the `mousedown|tapstart` event.
	},

	// Event when you move an item in the list or between lists
	onMove: function (/**Event*/evt, /**Event*/originalEvent) {
		// Example: https://jsbin.com/nawahef/edit?js,output
		evt.dragged; // dragged HTMLElement
		evt.draggedRect; // DOMRect {left, top, right, bottom}
		evt.related; // HTMLElement on which have guided
		evt.relatedRect; // DOMRect
		evt.willInsertAfter; // Boolean that is true if Sortable will insert drag element after target by default
		originalEvent.clientY; // mouse position
		// return false; — for cancel
		// return -1; — insert before target
		// return 1; — insert after target
		// return true; — keep default insertion point based on the direction
		// return void; — keep default insertion point based on the direction
	},

	// Called when creating a clone of element
	onClone: function (/**Event*/evt) {
		var origEl = evt.item;
		var cloneEl = evt.clone;
	},

	// Called when dragging element changes position
	onChange: function(/**Event*/evt) {
		evt.newIndex // most likely why this event is used is to get the dragging element's current index
		// same properties as onEnd
	}
});