Apps drag and drop feature

3 files changed, 146 insertions, 0 deletions

diff --git a/library/Sortable/plugins/Swap/README.md b/library/Sortable/plugins/Swap/README.md
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+## Swap Plugin
+This plugin modifies the behaviour of Sortable to allow for items to be swapped with eachother rather than sorted. Once dragging starts, the user can drag over other items and there will be no change in the elements. However, the item that the user drops on will be swapped with the originally dragged item.
+
+Demo: https://jsbin.com/yejehog/edit?html,js,output
+
+
+---
+
+
+### Mounting
+```js
+import { Sortable, Swap } from 'sortablejs/modular/sortable.core.esm';
+
+Sortable.mount(new Swap());
+```
+
+
+---
+
+
+### Options
+
+```js
+new Sortable(el, {
+	swap: true, // Enable swap mode
+	swapClass: "sortable-swap-highlight" // Class name for swap item (if swap mode is enabled)
+});
+```
+
+
+---
+
+
+#### `swapClass` option
+Class name for the item to be swapped with, if swap mode is enabled. Defaults to `sortable-swap-highlight`.
+
+```css
+.highlighted {
+  background-color: #9AB6F1;
+}
+```
+
+```js
+Sortable.create(list, {
+  swap: true,
+  swapClass: "highlighted"
+});
+```
+
+
+---
+
+
+### Event Properties
+ - swapItem:`HTMLElement|undefined` — The element that the dragged element was swapped with
diff --git a/library/Sortable/plugins/Swap/Swap.js b/library/Sortable/plugins/Swap/Swap.js
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+++ b/library/Sortable/plugins/Swap/Swap.js
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+import {
+	toggleClass,
+	index
+} from '../../src/utils.js';
+
+let lastSwapEl;
+
+
+function SwapPlugin() {
+	function Swap() {
+		this.defaults = {
+			swapClass: 'sortable-swap-highlight'
+		};
+	}
+
+	Swap.prototype = {
+		dragStart({ dragEl }) {
+			lastSwapEl = dragEl;
+		},
+		dragOverValid({ completed, target, onMove, activeSortable, changed, cancel }) {
+			if (!activeSortable.options.swap) return;
+			let el = this.sortable.el,
+				options = this.options;
+			if (target && target !== el) {
+				let prevSwapEl = lastSwapEl;
+				if (onMove(target) !== false) {
+					toggleClass(target, options.swapClass, true);
+					lastSwapEl = target;
+				} else {
+					lastSwapEl = null;
+				}
+
+				if (prevSwapEl && prevSwapEl !== lastSwapEl) {
+					toggleClass(prevSwapEl, options.swapClass, false);
+				}
+			}
+			changed();
+
+			completed(true);
+			cancel();
+		},
+		drop({ activeSortable, putSortable, dragEl }) {
+			let toSortable = (putSortable || this.sortable);
+			let options = this.options;
+			lastSwapEl && toggleClass(lastSwapEl, options.swapClass, false);
+			if (lastSwapEl && (options.swap || putSortable && putSortable.options.swap)) {
+				if (dragEl !== lastSwapEl) {
+					toSortable.captureAnimationState();
+					if (toSortable !== activeSortable) activeSortable.captureAnimationState();
+					swapNodes(dragEl, lastSwapEl);
+
+					toSortable.animateAll();
+					if (toSortable !== activeSortable) activeSortable.animateAll();
+				}
+			}
+		},
+		nulling() {
+			lastSwapEl = null;
+		}
+	};
+
+	return Object.assign(Swap, {
+		pluginName: 'swap',
+		eventProperties() {
+			return {
+				swapItem: lastSwapEl
+			};
+		}
+	});
+}
+
+
+function swapNodes(n1, n2) {
+	let p1 = n1.parentNode,
+		p2 = n2.parentNode,
+		i1, i2;
+
+	if (!p1 || !p2 || p1.isEqualNode(n2) || p2.isEqualNode(n1)) return;
+
+	i1 = index(n1);
+	i2 = index(n2);
+
+	if (p1.isEqualNode(p2) && i1 < i2) {
+		i2++;
+	}
+	p1.insertBefore(n2, p1.children[i1]);
+	p2.insertBefore(n1, p2.children[i2]);
+}
+
+export default SwapPlugin;
diff --git a/library/Sortable/plugins/Swap/index.js b/library/Sortable/plugins/Swap/index.js
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+++ b/library/Sortable/plugins/Swap/index.js
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+export { default } from './Swap.js';