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Make connections work on mobile devices

master
Adrian Heine 1 year ago
parent
commit
d4c49ed8f0
  1. 447
      DragDropTouch.js
  2. 1
      index.html
  3. 4
      src/display.js
  4. 7
      style.css

447
DragDropTouch.js

@ -0,0 +1,447 @@
var DragDropTouch;
(function (DragDropTouch_1) {
'use strict';
/**
* Object used to hold the data that is being dragged during drag and drop operations.
*
* It may hold one or more data items of different types. For more information about
* drag and drop operations and data transfer objects, see
* <a href="https://developer.mozilla.org/en-US/docs/Web/API/DataTransfer">HTML Drag and Drop API</a>.
*
* This object is created automatically by the @see:DragDropTouch singleton and is
* accessible through the @see:dataTransfer property of all drag events.
*/
var DataTransfer = (function () {
function DataTransfer() {
this._dropEffect = 'move';
this._effectAllowed = 'all';
this._data = {};
}
Object.defineProperty(DataTransfer.prototype, "dropEffect", {
/**
* Gets or sets the type of drag-and-drop operation currently selected.
* The value must be 'none', 'copy', 'link', or 'move'.
*/
get: function () {
return this._dropEffect;
},
set: function (value) {
this._dropEffect = value;
},
enumerable: true,
configurable: true
});
Object.defineProperty(DataTransfer.prototype, "effectAllowed", {
/**
* Gets or sets the types of operations that are possible.
* Must be one of 'none', 'copy', 'copyLink', 'copyMove', 'link',
* 'linkMove', 'move', 'all' or 'uninitialized'.
*/
get: function () {
return this._effectAllowed;
},
set: function (value) {
this._effectAllowed = value;
},
enumerable: true,
configurable: true
});
Object.defineProperty(DataTransfer.prototype, "types", {
/**
* Gets an array of strings giving the formats that were set in the @see:dragstart event.
*/
get: function () {
return Object.keys(this._data);
},
enumerable: true,
configurable: true
});
/**
* Removes the data associated with a given type.
*
* The type argument is optional. If the type is empty or not specified, the data
* associated with all types is removed. If data for the specified type does not exist,
* or the data transfer contains no data, this method will have no effect.
*
* @param type Type of data to remove.
*/
DataTransfer.prototype.clearData = function (type) {
if (type != null) {
delete this._data[type];
}
else {
this._data = null;
}
};
/**
* Retrieves the data for a given type, or an empty string if data for that type does
* not exist or the data transfer contains no data.
*
* @param type Type of data to retrieve.
*/
DataTransfer.prototype.getData = function (type) {
return this._data[type] || '';
};
/**
* Set the data for a given type.
*
* For a list of recommended drag types, please see
* https://developer.mozilla.org/en-US/docs/Web/Guide/HTML/Recommended_Drag_Types.
*
* @param type Type of data to add.
* @param value Data to add.
*/
DataTransfer.prototype.setData = function (type, value) {
this._data[type] = value;
};
/**
* Set the image to be used for dragging if a custom one is desired.
*
* @param img An image element to use as the drag feedback image.
* @param offsetX The horizontal offset within the image.
* @param offsetY The vertical offset within the image.
*/
DataTransfer.prototype.setDragImage = function (img, offsetX, offsetY) {
var ddt = DragDropTouch._instance;
ddt._imgCustom = img;
ddt._imgOffset = { x: offsetX, y: offsetY };
};
return DataTransfer;
}());
DragDropTouch_1.DataTransfer = DataTransfer;
/**
* Defines a class that adds support for touch-based HTML5 drag/drop operations.
*
* The @see:DragDropTouch class listens to touch events and raises the
* appropriate HTML5 drag/drop events as if the events had been caused
* by mouse actions.
*
* The purpose of this class is to enable using existing, standard HTML5
* drag/drop code on mobile devices running IOS or Android.
*
* To use, include the DragDropTouch.js file on the page. The class will
* automatically start monitoring touch events and will raise the HTML5
* drag drop events (dragstart, dragenter, dragleave, drop, dragend) which
* should be handled by the application.
*
* For details and examples on HTML drag and drop, see
* https://developer.mozilla.org/en-US/docs/Web/Guide/HTML/Drag_operations.
*/
var DragDropTouch = (function () {
/**
* Initializes the single instance of the @see:DragDropTouch class.
*/
function DragDropTouch() {
this._lastClick = 0;
// enforce singleton pattern
if (DragDropTouch._instance) {
throw 'DragDropTouch instance already created.';
}
// detect passive event support
// https://github.com/Modernizr/Modernizr/issues/1894
var supportsPassive = false;
document.addEventListener('test', function () { }, {
get passive() {
supportsPassive = true;
return true;
}
});
// listen to touch events
if ('ontouchstart' in document) {
var d = document, ts = this._touchstart.bind(this), tm = this._touchmove.bind(this), te = this._touchend.bind(this), opt = supportsPassive ? { passive: false, capture: false } : false;
d.addEventListener('touchstart', ts, opt);
d.addEventListener('touchmove', tm, opt);
d.addEventListener('touchend', te);
d.addEventListener('touchcancel', te);
}
}
/**
* Gets a reference to the @see:DragDropTouch singleton.
*/
DragDropTouch.getInstance = function () {
return DragDropTouch._instance;
};
// ** event handlers
DragDropTouch.prototype._touchstart = function (e) {
var _this = this;
if (this._shouldHandle(e)) {
// raise double-click and prevent zooming
if (Date.now() - this._lastClick < DragDropTouch._DBLCLICK) {
if (this._dispatchEvent(e, 'dblclick', e.target)) {
e.preventDefault();
this._reset();
return;
}
}
// clear all variables
this._reset();
// get nearest draggable element
var src = this._closestDraggable(e.target);
if (src) {
// give caller a chance to handle the hover/move events
if (!this._dispatchEvent(e, 'mousemove', e.target) &&
!this._dispatchEvent(e, 'mousedown', e.target)) {
// get ready to start dragging
this._dragSource = src;
this._ptDown = this._getPoint(e);
this._lastTouch = e;
e.preventDefault();
// show context menu if the user hasn't started dragging after a while
setTimeout(function () {
if (_this._dragSource == src && _this._img == null) {
if (_this._dispatchEvent(e, 'contextmenu', src)) {
_this._reset();
}
}
}, DragDropTouch._CTXMENU);
if (DragDropTouch._ISPRESSHOLDMODE) {
this._pressHoldInterval = setTimeout(function () {
_this._isDragEnabled = true;
_this._touchmove(e);
}, DragDropTouch._PRESSHOLDAWAIT);
}
}
}
}
};
DragDropTouch.prototype._touchmove = function (e) {
if (this._shouldCancelPressHoldMove(e)) {
this._reset();
return;
}
if (this._shouldHandleMove(e) || this._shouldHandlePressHoldMove(e)) {
// see if target wants to handle move
var target = this._getTarget(e);
if (this._dispatchEvent(e, 'mousemove', target)) {
this._lastTouch = e;
e.preventDefault();
return;
}
// start dragging
if (this._dragSource && !this._img && this._shouldStartDragging(e)) {
this._dispatchEvent(e, 'dragstart', this._dragSource);
this._createImage(e);
this._dispatchEvent(e, 'dragenter', target);
}
// continue dragging
if (this._img) {
this._lastTouch = e;
e.preventDefault(); // prevent scrolling
if (target != this._lastTarget) {
this._dispatchEvent(this._lastTouch, 'dragleave', this._lastTarget);
this._dispatchEvent(e, 'dragenter', target);
this._lastTarget = target;
}
this._moveImage(e);
this._isDropZone = this._dispatchEvent(e, 'dragover', target);
}
}
};
DragDropTouch.prototype._touchend = function (e) {
if (this._shouldHandle(e)) {
// see if target wants to handle up
if (this._dispatchEvent(this._lastTouch, 'mouseup', e.target)) {
e.preventDefault();
return;
}
// user clicked the element but didn't drag, so clear the source and simulate a click
if (!this._img) {
this._dragSource = null;
this._dispatchEvent(this._lastTouch, 'click', e.target);
this._lastClick = Date.now();
}
// finish dragging
this._destroyImage();
if (this._dragSource) {
if (e.type.indexOf('cancel') < 0 && this._isDropZone) {
this._dispatchEvent(this._lastTouch, 'drop', this._lastTarget);
}
this._dispatchEvent(this._lastTouch, 'dragend', this._dragSource);
this._reset();
}
}
};
// ** utilities
// ignore events that have been handled or that involve more than one touch
DragDropTouch.prototype._shouldHandle = function (e) {
return e &&
!e.defaultPrevented &&
e.touches && e.touches.length < 2;
};
// use regular condition outside of press & hold mode
DragDropTouch.prototype._shouldHandleMove = function (e) {
return !DragDropTouch._ISPRESSHOLDMODE && this._shouldHandle(e);
};
// allow to handle moves that involve many touches for press & hold
DragDropTouch.prototype._shouldHandlePressHoldMove = function (e) {
return DragDropTouch._ISPRESSHOLDMODE &&
this._isDragEnabled && e && e.touches && e.touches.length;
};
// reset data if user drags without pressing & holding
DragDropTouch.prototype._shouldCancelPressHoldMove = function (e) {
return DragDropTouch._ISPRESSHOLDMODE && !this._isDragEnabled &&
this._getDelta(e) > DragDropTouch._PRESSHOLDMARGIN;
};
// start dragging when specified delta is detected
DragDropTouch.prototype._shouldStartDragging = function (e) {
var delta = this._getDelta(e);
return delta > DragDropTouch._THRESHOLD ||
(DragDropTouch._ISPRESSHOLDMODE && delta >= DragDropTouch._PRESSHOLDTHRESHOLD);
}
// clear all members
DragDropTouch.prototype._reset = function () {
this._destroyImage();
this._dragSource = null;
this._lastTouch = null;
this._lastTarget = null;
this._ptDown = null;
this._isDragEnabled = false;
this._isDropZone = false;
this._dataTransfer = new DataTransfer();
clearInterval(this._pressHoldInterval);
};
// get point for a touch event
DragDropTouch.prototype._getPoint = function (e, page) {
if (e && e.touches) {
e = e.touches[0];
}
return { x: page ? e.pageX : e.clientX, y: page ? e.pageY : e.clientY };
};
// get distance between the current touch event and the first one
DragDropTouch.prototype._getDelta = function (e) {
if (DragDropTouch._ISPRESSHOLDMODE && !this._ptDown) { return 0; }
var p = this._getPoint(e);
return Math.abs(p.x - this._ptDown.x) + Math.abs(p.y - this._ptDown.y);
};
// get the element at a given touch event
DragDropTouch.prototype._getTarget = function (e) {
var pt = this._getPoint(e), el = document.elementFromPoint(pt.x, pt.y);
while (el && getComputedStyle(el).pointerEvents == 'none') {
el = el.parentElement;
}
return el;
};
// create drag image from source element
DragDropTouch.prototype._createImage = function (e) {
// just in case...
if (this._img) {
this._destroyImage();
}
// create drag image from custom element or drag source
var src = this._imgCustom || this._dragSource;
this._img = src.cloneNode(true);
this._copyStyle(src, this._img);
this._img.style.top = this._img.style.left = '-9999px';
// if creating from drag source, apply offset and opacity
if (!this._imgCustom) {
var rc = src.getBoundingClientRect(), pt = this._getPoint(e);
this._imgOffset = { x: pt.x - rc.left, y: pt.y - rc.top };
this._img.style.opacity = DragDropTouch._OPACITY.toString();
}
// add image to document
this._moveImage(e);
document.body.appendChild(this._img);
};
// dispose of drag image element
DragDropTouch.prototype._destroyImage = function () {
if (this._img && this._img.parentElement) {
this._img.parentElement.removeChild(this._img);
}
this._img = null;
this._imgCustom = null;
};
// move the drag image element
DragDropTouch.prototype._moveImage = function (e) {
var _this = this;
requestAnimationFrame(function () {
if (_this._img) {
var pt = _this._getPoint(e, true), s = _this._img.style;
s.position = 'absolute';
s.pointerEvents = 'none';
s.zIndex = '999999';
s.left = Math.round(pt.x - _this._imgOffset.x) + 'px';
s.top = Math.round(pt.y - _this._imgOffset.y) + 'px';
}
});
};
// copy properties from an object to another
DragDropTouch.prototype._copyProps = function (dst, src, props) {
for (var i = 0; i < props.length; i++) {
var p = props[i];
dst[p] = src[p];
}
};
DragDropTouch.prototype._copyStyle = function (src, dst) {
// remove potentially troublesome attributes
DragDropTouch._rmvAtts.forEach(function (att) {
dst.removeAttribute(att);
});
// copy canvas content
if (src instanceof HTMLCanvasElement) {
var cSrc = src, cDst = dst;
cDst.width = cSrc.width;
cDst.height = cSrc.height;
cDst.getContext('2d').drawImage(cSrc, 0, 0);
}
// copy style (without transitions)
var cs = getComputedStyle(src);
for (var i = 0; i < cs.length; i++) {
var key = cs[i];
if (key.indexOf('transition') < 0) {
dst.style[key] = cs[key];
}
}
dst.style.pointerEvents = 'none';
// and repeat for all children
for (var i = 0; i < src.children.length; i++) {
this._copyStyle(src.children[i], dst.children[i]);
}
};
DragDropTouch.prototype._dispatchEvent = function (e, type, target) {
if (e && target) {
var evt = document.createEvent('Event'), t = e.touches ? e.touches[0] : e;
evt.initEvent(type, true, true);
evt.button = 0;
evt.which = evt.buttons = 1;
this._copyProps(evt, e, DragDropTouch._kbdProps);
this._copyProps(evt, t, DragDropTouch._ptProps);
evt.dataTransfer = this._dataTransfer;
target.dispatchEvent(evt);
return evt.defaultPrevented;
}
return false;
};
// gets an element's closest draggable ancestor
DragDropTouch.prototype._closestDraggable = function (e) {
for (; e; e = e.parentElement) {
if (e.hasAttribute('draggable') && e.draggable) {
return e;
}
}
return null;
};
return DragDropTouch;
}());
/*private*/ DragDropTouch._instance = new DragDropTouch(); // singleton
// constants
DragDropTouch._THRESHOLD = 5; // pixels to move before drag starts
DragDropTouch._OPACITY = 0.5; // drag image opacity
DragDropTouch._DBLCLICK = 500; // max ms between clicks in a double click
DragDropTouch._CTXMENU = 900; // ms to hold before raising 'contextmenu' event
DragDropTouch._ISPRESSHOLDMODE = false; // decides of press & hold mode presence
DragDropTouch._PRESSHOLDAWAIT = 400; // ms to wait before press & hold is detected
DragDropTouch._PRESSHOLDMARGIN = 25; // pixels that finger might shiver while pressing
DragDropTouch._PRESSHOLDTHRESHOLD = 0; // pixels to move before drag starts
// copy styles/attributes from drag source to drag image element
DragDropTouch._rmvAtts = 'id,class,style,draggable'.split(',');
// synthesize and dispatch an event
// returns true if the event has been handled (e.preventDefault == true)
DragDropTouch._kbdProps = 'altKey,ctrlKey,metaKey,shiftKey'.split(',');
DragDropTouch._ptProps = 'pageX,pageY,clientX,clientY,screenX,screenY,offsetX,offsetY'.split(',');
DragDropTouch_1.DragDropTouch = DragDropTouch;
})(DragDropTouch || (DragDropTouch = {}));

1
index.html

@ -4,6 +4,7 @@
<link rel="stylesheet" href="/style.css">
<script src=/diffDOM.js></script>
<script src=/springy.js></script>
<script src=/DragDropTouch.js></script>
<script src=/src/index.js type=module></script>
<div class=wrapper></div>
<aside>

4
src/display.js

@ -28,7 +28,9 @@ export class Display {
target.addEventListener('dragstart', e => {
let target = findA(e.target)
if (!target || !target.draggable) return
e.dataTransfer.clearData()
// https://github.com/Bernardo-Castilho/dragdroptouch/pull/37
// e.dataTransfer.clearData()
for (const x of e.dataTransfer.types) { e.dataTransfer.clearData(x) }
e.dataTransfer.setData('application/prs.x', target.dataset['id'])
e.dataTransfer.effectAllowed = 'link'
})

7
style.css

@ -68,11 +68,16 @@ body {
text-align: center;
position: absolute;
transform-origin: 0 0;
font-size: 1.2em;
padding: 0 min(6vh, 6vw);
box-sizing: border-box;
}
@media (min-width: 30em) {
.line {
font-size: 1.2em;
}
}
.fullview {
width: 100%;
height: 100%;

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