使用鼠标拖动来控制背景位置

Question

我想使用'鼠标拖动'在框内拖动背景的位置.

css:

.filmmakers #map {

   width : 920px;

   height : 500px;

   margin-top : 50px;

   margin-left : 38px;

   border : 1px solid rgb(0, 0, 0);

   cursor : move;

   overflow : hidden;

   background-image : url('WorldMap.png');

   background-repeat : no-repeat;

}

html:

<div id = "map" src = "WorldMap.png" onmousedown = "MouseMove(this)"> </div>

javascript:

function MouseMove (e) {

   var x = e.clientX;

   var y = e.clientY;

    e.style.backgroundPositionX = x + 'px';

    e.style.backgroundPositionY = y + 'px';

    e.style.cursor = "move";

}

什么都没有发生,没有错误,没有警告,什么都没有......我尝试了很多东西:div内部的绝对定位图像(你可以猜到为什么不起作用),一个带有背景图像的div内的可拖动div,一个拖放的表,最后我尝试了这个:

function MouseMove () {

    e.style.backgroundPositionX = 10 + 'px';

    e.style.backgroundPositionY = 10 + 'px';

    e.style.cursor = "move";

}

这有效,但它与鼠标的位置无关,pageX和pageY也不起作用.

现场演示:http://jsfiddle.net/VRvUB/224/

PS:不管你的想法是什么,请不要用JQuery编写

干杯!

Mithos

Answer 1

根据您的问题,我了解您需要帮助实现实际的"拖动"行为.我猜不会.无论如何,这是我努力的结果:http://jsfiddle.net/joplomacedo/VRvUB/236/

拖动只发生在鼠标按钮上,而且......好吧,它表现得像我想你想要的那样.如果你没有=)只是看小提琴

以下是想要在此处查看的人的代码:

var AttachDragTo = (function () {
    var _AttachDragTo = function (el) {
        this.el = el;
        this.mouse_is_down = false;

        this.init();
    };

    _AttachDragTo.prototype = {
        onMousemove: function (e) {
            if ( !this.mouse_is_down ) return;
            var tg = e.target,
                x = e.clientX,
                y = e.clientY;

            tg.style.backgroundPositionX = x - this.origin_x + this.origin_bg_pos_x + 'px';
            tg.style.backgroundPositionY = y - this.origin_y + this.origin_bg_pos_y + 'px';
        },

        onMousedown: function(e) {
            this.mouse_is_down = true;
            this.origin_x = e.clientX;
            this.origin_y = e.clientY;
        },

        onMouseup: function(e) {
            var tg = e.target,
                styles = getComputedStyle(tg);

            this.mouse_is_down = false;
            this.origin_bg_pos_x = parseInt(styles.getPropertyValue('background-position-x'), 10);
            this.origin_bg_pos_y = parseInt(styles.getPropertyValue('background-position-y'), 10);
        },

        init: function () {
            var styles = getComputedStyle(this.el);
            this.origin_bg_pos_x = parseInt(styles.getPropertyValue('background-position-x'), 10);
            this.origin_bg_pos_y = parseInt(styles.getPropertyValue('background-position-y'), 10);

            //attach events
            this.el.addEventListener('mousedown', this.onMousedown.bind(this), false);
            this.el.addEventListener('mouseup', this.onMouseup.bind(this), false);
            this.el.addEventListener('mousemove', this.onMousemove.bind(this), false);
        }
    };

    return function ( el ) {
        new _AttachDragTo(el);
    };
})();


/*** IMPLEMENTATION ***/
//1. Get your element.
var map = document.getElementById('map');
//2. Attach the drag.
AttachDragTo(map);
?