讓 jQuery UI draggable 適配移動端

時間 2019-11-21

原文原文鏈接

背景：css

在移動端，本人要實現對某個元素的拖動，想到使用 jQuery UI 的 draggable 功能。可是發現此插件的拖動只支持PC端，不支持移動端。html

緣由：jquery

原始的 jQuery UI 裏，都是mousedown、mousemove、mouseup來描述拖拽和鼠標的點擊事件，而在移動端裏，確定要新添touchstart、touchmove、touchend來描述拖拽和手指的點擊事件瀏覽器

實現 demo：app

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=0;" name="viewport">
    <title>jQuery UI draggable 適配移動端</title>
</head>
<body>
<img id="img" src="http://placehold.it/200x100">

<script src="//cdn.bootcss.com/jquery/3.0.0-beta1/jquery.js"></script>
<script src="//cdn.bootcss.com/jqueryui/1.11.4/jquery-ui.min.js"></script>
<script>

    // jQuery UI draggable 適配移動端

    var moveFlag = 0; // 是否移動的flag
    // /iPad|iPhone|Android/.test( navigator.userAgent ) &&
    (function ($) {
        var proto = $.ui.mouse.prototype, _mouseInit = proto._mouseInit;
        $.extend(proto, {
            _mouseInit: function () {
                this.element.bind("touchstart." + this.widgetName, $.proxy(this, "_touchStart"));
                _mouseInit.apply(this, arguments);
            }, _touchStart: function (event) {
                this.element.bind("touchmove." + this.widgetName, $.proxy(this, "_touchMove")).bind("touchend." + this.widgetName, $.proxy(this, "_touchEnd"));
                this._modifyEvent(event);
                $(document).trigger($.Event("mouseup"));
                //reset mouseHandled flag in ui.mouse
                this._mouseDown(event);
                //console.log(this);
                //return false;

                //--------------------touchStart do something--------------------
 console.log("i touchStart!");

            }, _touchMove: function (event) {
                moveFlag = 1;
                this._modifyEvent(event);
                this._mouseMove(event);

                //--------------------touchMove do something--------------------
 console.log("i touchMove!");

            }, _touchEnd: function (event) {
                // 主動觸發點擊事件
                if (moveFlag == 0) {
                    var evt = document.createEvent('Event');
                    evt.initEvent('click', true, true);
                    this.handleElement[0].dispatchEvent(evt);
                }
                this.element.unbind("touchmove." + this.widgetName).unbind("touchend." + this.widgetName);
                this._mouseUp(event);
                moveFlag = 0;

                //--------------------touchEnd do something--------------------
 console.log("i touchEnd!");

            }, _modifyEvent: function (event) {
                event.which = 1;
                var target = event.originalEvent.targetTouches[0];
                event.pageX = target.clientX;
                event.pageY = target.clientY;
            }
        });
    })(jQuery);

</script>
<script>
    // my js
    $("#img").draggable();
</script>
</body>
</html>