Aurelia Oribella Sortable Gist New

app.html

<template>
  <ul oa-sortable="scroll.bind: 'document'; items.bind: items; axis: 'y'">
    <li
      oa-sortable-item="item.bind: item;"
      repeat.for="item of items"
      draggable="false">
      ${item.text}
    </li>
  </ul>
</template>

app.js

export class App {
  items = [
      { text: '1' },
      { text: '2' },
      { text: '3' },
      { text: '4' },
      { text: '5' },
      { text: '6' },
      { text: '7' },
      { text: '8' },
      { text: '9' },
      { text: '10' }
    ];
}

auto-scroll.js

import {transient} from "aurelia-dependency-injection";

@transient()
export class AutoScroll {
  rAFId = -1;
  speed = 10;
  active = false;

  start(speed = 10) {
    this.speed = speed;
  }
  update(element, dirX, dirY, frameCntX, frameCntY) {
    if (this.active) {
      if (dirX === 0 && dirY === 0) {
        cancelAnimationFrame(this.rAFId);
        this.active = false;
      }
      return;
    }
    if (dirX === 0 && dirY === 0) {
      return;
    }

    if (frameCntX === 0 && frameCntY === 0) {
      return;
    }

    const scrollDeltaX = dirX * this.speed;
    const scrollDeltaY = dirY * this.speed;

    const autoScroll = () => {

      if ( !this.active ) {
        return;
      }
      if (frameCntX > 0) {
        element.scrollLeft += scrollDeltaX;
      }
      if (frameCntY > 0) {
        element.scrollTop += scrollDeltaY;
      }

      --frameCntX;
      --frameCntY;
      if (frameCntX <= 0 && frameCntY <= 0) {
        this.active = false;
        return;
      }

      this.rAFId = requestAnimationFrame(autoScroll);
    };

    this.active = true;
    autoScroll();
  }
  end(cAF = cancelAnimationFrame) {
    cAF(this.rAFId);
    this.active = false;
  }
}

config.js

require.config({
  baseUrl: ".",
  paths: {
  },
  packages: [
    {
      name: 'sortable',
      location: '.',
      main: 'index'
    }
  ],
  config: {
    es6: { stage: 0 }
  }
});

require.load = function(context, moduleName, url) {
  require(['es6'], function(es6) {
    es6.load(
      moduleName,
      require,
      {
        fromText: function(text) {
          require.exec(text);
          context.completeLoad(moduleName);
        }
      },
      {});
  });
};

drag.js

import {transient} from "aurelia-dependency-injection";

@transient()
export class Drag {
  startLeft = 0;
  startTop = 0;
  rect = { left: 0, top: 0, width: 0, height: 0 };
  offsetX = 0;
  offsetY = 0;

  pin() {
    this.item.sortingClass = this.sortingClass;
    this.clone = this.element.cloneNode(true);
    this.clone.style.position = "absolute";
    this.clone.style.width = this.rect.width + "px";
    this.clone.style.height = this.rect.height + "px";
    this.clone.style.pointerEvents = "none";
    this.clone.style.margin = 0;
    this.clone.style.zIndex = this.dragZIndex;
    document.body.appendChild(this.clone);
  }
  unpin() {
    this.item.sortingClass = "";
    document.body.removeChild(this.clone);
    this.clone = null;
  }
  getCenterX() {
    return this.rect.left + this.rect.width / 2;
  }
  getCenterY() {
    return this.rect.top + this.rect.height / 2;
  }
  start(element, item, x, y, viewportScroll, scrollLeft, scrollTop, dragZIndex, axis, sortingClass, minPosX, maxPosX, minPosY, maxPosY) {
    this.element = element;
    this.item = item;
    this.sortingClass = sortingClass;
    this.dragZIndex = dragZIndex;
    const rect = (this.rect = element.getBoundingClientRect());

    this.startLeft = rect.left;
    this.startTop = rect.top;

    this.offsetX = this.startLeft - x;
    this.offsetY = this.startTop - y;

    this.pin();

    this.update(x, y, viewportScroll, scrollLeft, scrollTop, axis, minPosX, maxPosX, minPosY, maxPosY);
  }
  update(x, y, viewportScroll, scrollLeft, scrollTop, axis, minPosX, maxPosX, minPosY, maxPosY) {
    x += this.offsetX;
    y += this.offsetY;
    if (viewportScroll) {
      x += scrollLeft;
      y += scrollTop;
    }

    if (x < minPosX) {
      x = minPosX;
    }
    if (x > maxPosX - this.rect.width) {
      x = maxPosX - this.rect.width;
    }

    if (y < minPosY) {
      y = minPosY;
    }
    if (y > maxPosY - this.rect.height) {
      y = maxPosY - this.rect.height;
    }

    switch (axis) {
    case "x":
      y = this.startTop;
      break;
    case "y":
      x = this.startLeft;
      break;
    }

    this.clone.style.left = x + "px";
    this.clone.style.top = y + "px";
  }
  end() {
    if (this.element === null) {
      return;
    }
    this.unpin();
    this.element = null;
    this.item = null;
  }
}

index.html

<!doctype html>
<html>
  <head>
    <title>Aurelia</title>
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link href="styles.css" rel="stylesheet">
  </head>
  <body aurelia-app="main">
    <h1>Loading...</h1>
    
    <script src="https://jdanyow.github.io/rjs-bundle/node_modules/requirejs/require.js"></script>
    <script src="https://jdanyow.github.io/rjs-bundle/bundles/aurelia.js"></script>
    <script src="https://jdanyow.github.io/rjs-bundle/bundles/babel.js"></script>
    <script src="https://unpkg.com/oribella/dist/oribella-inline-source-map.js"></script>
    <script src="config.js"></script>
    <script>
      require(['aurelia-bootstrapper']);
    </script>
  </body>
</html>

index.js

export function configure(config) {
  config.globalResources("./sortable");
}

main.js

export function configure(aurelia) {
  aurelia.use
    .standardConfiguration()
    .developmentLogging()
    .plugin('sortable');

  aurelia.start().then(() => aurelia.setRoot());
}

sortable.js

import {DOM} from "aurelia-pal";
import {customAttribute, bindable} from "aurelia-templating";
import {inject, transient} from "aurelia-dependency-injection";
import {oribella, Swipe, matchesSelector, GESTURE_STRATEGY_FLAG} from 'oribella';
import {Drag} from "./drag";
import {AutoScroll} from "./auto-scroll";

const SORTABLE_ITEM = "oa-sortable-item";

@customAttribute("oa-sortable")
@inject(DOM.Element, Drag, AutoScroll)
@transient()
export class Sortable {

  @bindable scroll = null;
  @bindable scrollSpeed = 10;
  @bindable scrollSensitivity = 10;
  @bindable items = [];
  @bindable sortingClass = "oa-sorting";
  @bindable draggingClass = "oa-dragging";
  @bindable axis = "";
  @bindable moved = () => {};
  @bindable dragZIndex = 1;
  @bindable disallowedDragTagNames = ["INPUT", "SELECT", "TEXTAREA"];
  @bindable allowDrag = args => {
    if (this.disallowedDragTagNames.indexOf(args.event.target.tagName) !== -1) {
      return false;
    }
    if (args.event.target.isContentEditable) {
      return false;
    }
    return true;
  };
  @bindable allowMove = () => { return true; };

  selector = "[" + SORTABLE_ITEM + "]";
  fromIx = -1;
  toIx = -1;
  x = 0;
  y = 0;
  lastElementFromPointRect = null;

  constructor(element, drag, autoScroll) {
    this.element = element;
    this.drag = drag;
    this.autoScroll = autoScroll;
    this.options = {
      strategy: GESTURE_STRATEGY_FLAG.REMOVE_IF_POINTERS_GT
    };
  }
  activate() {
    this.removeListener = oribella.on(Swipe, this.element, this);
    let scroll = this.scroll;
    if (typeof scroll === "string") {
      if (scroll === "document") {
        this.scroll = document.scrollingElement || document.documentElement || document.body;
        this.viewportScroll = true;
        this.removeScroll = this.bindScroll(document, this.onScroll.bind(this));
        return;
      } else {
        scroll = this.closest(this.element, scroll);
      }
    }
    this.scroll = scroll;
    if (!(this.scroll instanceof DOM.Element)) {
      this.scroll = this.element;
    }
    this.removeScroll = this.bindScroll(this.scroll, this.onScroll.bind(this));
  }
  deactivate() {
    if (typeof this.removeListener === "function") {
      this.removeListener();
    }
    if (typeof this.removeScroll === "function") {
      this.removeScroll();
    }
  }
  attached() {
    this.activate();
  }
  detached() {
    this.deactivate();
  }
  bindScroll(scroll, fn) {
    scroll.addEventListener("scroll", fn, false);
    return () => {
      scroll.removeEventListener("scroll", fn, false);
    };
  }
  onScroll() {
    if (!this.drag.element) {
      return;
    }
    const { scrollLeft, scrollTop } = this.scroll;
    this.drag.update(this.x,
      this.y,
      this.viewportScroll,
      scrollLeft,
      scrollTop,
      this.axis,
      this.dragMinPosX,
      this.dragMaxPosX,
      this.dragMinPosY,
      this.dragMaxPosY);
    const { x, y } = this.getPoint(this.x, this.y);
    this.tryMove(x, y, scrollLeft, scrollTop);
  }
  getScrollFrames(maxPos, scrollPos) {
    return Math.max(0, Math.ceil(Math.abs(maxPos - scrollPos) / this.scrollSpeed));
  }
  getScrollDirectionX(x, { left, right }) {
    let dir = 0;
    switch (this.axis) {
      default:
      case "x":
      if (x >= right - this.scrollSensitivity) {
        dir = 1;
      } else if (x <= left + this.scrollSensitivity) {
        dir = -1;
      }
      break;
    }
    return dir;
  }
  getScrollDirectionY(y, { top, bottom }) {
    let dir = 0;
    switch (this.axis) {
      default:
      case "y":
      if (y >= bottom - this.scrollSensitivity) {
        dir = 1;
      } else if (y <= top + this.scrollSensitivity) {
        dir = -1;
      }
      break;
    }
    return dir;
  }
  hide(element) {
    const display = element.style.display;
    element.style.display = "none";
    return () => {
      element.style.display = display;
    };
  }
  closest(element, selector, rootElement = document) {
    var valid = false;
    while (!valid && element !== null && element !== rootElement &&
      element !== document) {
      valid = matchesSelector(element, selector);
      if (valid) {
        break;
      }
      element = element.parentNode;
    }
    return valid ? element : null;
  }
  getItemViewModel(element) {
    return element.au[SORTABLE_ITEM].viewModel;
  }
  moveSortingItem(toIx) {
    const fromIx = this.items.indexOf(this.drag.item);
    this.toIx = toIx;
    this.move(fromIx, toIx);
  }
  move(fromIx, toIx) {
    if (fromIx !== -1 && toIx !== -1 && fromIx !== toIx) {
      this.items.splice(toIx, 0, this.items.splice(fromIx, 1)[0]);
    }
  }
  tryUpdate(x, y, offsetX, offsetY) {
    const showFn = this.hide(this.drag.clone);
    this.tryMove(x, y, offsetX, offsetY);
    showFn();
  }
  pointInside(x, y, rect) {
    return x >= rect.left &&
      x <= rect.right &&
      y >= rect.top &&
      y <= rect.bottom;
  }
  elementFromPoint(x, y) {
    let element = document.elementFromPoint(x, y);
    if (!element) {
      return null;
    }
    element = this.closest(element, this.selector, this.element);
    if (!element) {
      return null;
    }
    return element;
  }
  canThrottle(x, y, offsetX, offsetY) {
    return this.lastElementFromPointRect &&
      this.pointInside(x + offsetX, y + offsetY, this.lastElementFromPointRect);
  }
  tryMove(x, y, offsetX, offsetY) {
    if (this.canThrottle(x, y, offsetX, offsetY)) {
      return;
    }
    const element = this.elementFromPoint(x, y);
    if (!element) {
      return;
    }
    const vm = this.getItemViewModel(element);
    this.lastElementFromPointRect = element.getBoundingClientRect();
    if (!this.allowMove({ item: vm.item })) {
      return;
    }
    this.moveSortingItem(vm.ctx.$index);
  }
  getPoint(pageX, pageY) {
    switch (this.axis) {
    case "x":
      pageY = this.drag.getCenterY();
      break;
    case "y":
      pageX = this.drag.getCenterX();
      break;
    default:
      break;
    }
    return {
      x: pageX,
      y: pageY
    };
  }
  down(e, data, element) {
    if (this.allowDrag({ event: e, item: this.getItemViewModel(element).item })) {
      e.preventDefault();
      return undefined;
    }
    return false;
  }
  start(e, data, element) {
    const { scrollLeft, scrollTop } = this.scroll;

    this.windowHeight = innerHeight;
    this.windowWidth = innerWidth;
    this.x = data.pointers[0].client.x;
    this.y = data.pointers[0].client.y;
    this.sortableRect = this.element.getBoundingClientRect();

    this.scrollRect = this.scroll.getBoundingClientRect();
    this.scrollWidth = this.scroll.scrollWidth;
    this.scrollHeight = this.scroll.scrollHeight;

    this.boundingRect = {
      left: Math.max(0, this.sortableRect.left),
      top: Math.max(0, this.sortableRect.top),
      bottom: Math.min(this.windowHeight, this.sortableRect.bottom),
      right: Math.min(this.windowWidth, this.sortableRect.right)
    };

    this.sortableContainsScroll = this.element.contains(this.scroll);
    if (this.sortableContainsScroll) {
      this.scrollMaxPosX = this.scrollWidth - this.scrollRect.width;
      this.scrollMaxPosY = this.scrollHeight - this.scrollRect.height;
      this.dragMinPosX = this.sortableRect.left;
      this.dragMaxPosX = this.sortableRect.left + this.scrollWidth;
      this.dragMaxPosY = this.sortableRect.top + this.scrollHeight;
      this.dragMinPosY = this.sortableRect.top;
    } else {
      this.scrollMaxPosX = this.sortableRect.right - this.windowWidth + (this.viewportScroll ? scrollLeft : 0);
      this.scrollMaxPosY = this.sortableRect.bottom - this.windowHeight + (this.viewportScroll ? scrollTop : 0);
      this.dragMinPosX = this.sortableRect.left + scrollLeft;
      this.dragMaxPosX = this.scrollMaxPosX + this.windowWidth;
      this.dragMinPosY = this.sortableRect.top + scrollTop;
      this.dragMaxPosY = this.scrollMaxPosY + this.windowHeight;
    }

    this.sortingViewModel = this.getItemViewModel(element);
    this.fromIx = this.sortingViewModel.ctx.$index;
    this.toIx = -1;

    this.drag.start( element,
      this.sortingViewModel.item,
      this.x, this.y,
      this.viewportScroll,
      scrollLeft,
      scrollTop,
      this.dragZIndex,
      this.axis, this.sortingClass,
      this.dragMinPosX,
      this.dragMaxPosX,
      this.dragMinPosY,
      this.dragMaxPosY);
    this.autoScroll.start(this.scrollSpeed);
    this.lastElementFromPointRect = this.drag.rect;
  }
  update(e, data) {
    const p = data.pointers[0].client;
    const { scrollLeft, scrollTop } = this.scroll;
    this.x = p.x;
    this.y = p.y;
    this.drag.update(this.x,
      this.y,
      this.viewportScroll,
      scrollLeft,
      scrollTop,
      this.axis,
      this.dragMinPosX,
      this.dragMaxPosX,
      this.dragMinPosY,
      this.dragMaxPosY);
    const { x, y } = this.getPoint(p.x, p.y);
    const scrollX = this.autoScroll.active ? scrollLeft : 0;
    const scrollY = this.autoScroll.active ? scrollTop : 0;
    this.tryUpdate(x, y, scrollX, scrollY);

    const dirX = this.getScrollDirectionX(x, this.boundingRect);
    const dirY = this.getScrollDirectionY(y, this.boundingRect);
    let frameCntX = this.getScrollFrames(dirX === -1 ? 0 : this.scrollMaxPosX, scrollLeft);
    let frameCntY = this.getScrollFrames(dirY === -1 ? 0 : this.scrollMaxPosY, scrollTop);
    if ((dirX === 1 && scrollLeft >= this.scrollMaxPosX) ||
      (dirX === -1 && scrollLeft === 0)) {
      frameCntX = 0;
    }
    if ((dirY === 1 && scrollTop >= this.scrollMaxPosY) ||
      (dirY === -1 && scrollTop === 0)) {
      frameCntY = 0;
    }
    this.autoScroll.update(this.scroll, dirX, dirY, frameCntX, frameCntY);
  }
  end() {
    if (!this.drag.item) {
      return; //cancelled
    }
    this.stop();
    if (this.fromIx !== this.toIx) {
      this.moved( { fromIx: this.fromIx, toIx: this.toIx } );
    }
  }
  cancel() {
    this.move(this.sortingViewModel.ctx.$index, this.fromIx);
    this.stop();
  }
  stop() {
    this.drag.end();
    this.autoScroll.end();
  }
}

@customAttribute("oa-sortable-item")
export class SortableItem {

  @bindable item = null;

  bind(ctx, overrideCtx) {
    this.ctx = overrideCtx; //Need a reference to the item's $index
  }
}

styles.css

html, body {
  padding: 8px;
  margin: 0;
}
ul {
  padding: 0;
  margin: 0;
  list-style: none;
}
li {
  box-sizing: border-box;
  margin: 4px 0px;
  border: 1px solid #999;
  line-height: 2rem;
  text-align: center;
  list-style: none;
}