interactjs/src/legacyBrowsers.js

Drag and drop, resizing and multi-touch gestures with inertia and snapping for modern browsers (and also IE8+)

const scope         = require('./scope');
const events        = require('./utils/events');
const browser       = require('./utils/browser');
const iFinder       = require('./utils/interactionFinder');
const pointerEvents = require('./pointerEvents/base');

const { window } = require('./utils/window');

const toString = Object.prototype.toString;

if (!window.Array.isArray) {
  window.Array.isArray = function (obj) {
    return toString.call(obj) === '[object Array]';
  };
}

if (!String.prototype.trim) {
  String.prototype.trim = function () {
    return this.replace(/^[\s\uFEFF\xA0]+|[\s\uFEFF\xA0]+$/g, '');
  };
}

// http://www.quirksmode.org/dom/events/click.html
// >Events leading to dblclick
//
// IE8 doesn't fire down event before dblclick.
// This workaround tries to fire a tap and doubletap after dblclick
function onIE8Dblclick (event) {
  const eventTarget = event.target;
  const interaction = iFinder.search(event, event.type, eventTarget);

  if (!interaction) { return; }

  if (interaction.prevTap
      && event.clientX === interaction.prevTap.clientX
      && event.clientY === interaction.prevTap.clientY
      && eventTarget   === interaction.prevTap.target) {

    interaction.downTargets[0] = eventTarget;
    interaction.downTimes  [0] = new Date().getTime();

    pointerEvents.fire({
      interaction,
      event,
      eventTarget,
      pointer: event,
      type: 'tap',
    });
  }
}

if (browser.isIE8) {
  const selectFix = function (event) {
    for (const interaction of scope.interactions) {
      if (interaction.interacting()) {
        interaction.target.checkAndPreventDefault(event);
      }
    }
  };

  const onDocIE8 = function onDocIE8 ({ doc, win }, signalName) {
    const eventMethod = signalName.indexOf('listen') === 0
      ? events.add : events.remove;

    // For IE's lack of Event#preventDefault
    eventMethod(doc, 'selectstart', selectFix);

    if (pointerEvents) {
      eventMethod(doc, 'dblclick', onIE8Dblclick);
    }
  };

  scope.signals.on('add-document'   , onDocIE8);
  scope.signals.on('remove-document', onDocIE8);
}

module.exports = null;