抛开兼容性,HTML5 提供的一系列 API 可以简化很多代码量。
最终效果:
<ul id="columns">
<li class="column" draggable="true"><header>A</header></li>
<li class="column" draggable="true"><header>B</header></li>
<li class="column" draggable="true"><header>C</header></li>
<li class="column" draggable="true"><header>D</header></li>
<li class="column" draggable="true"><header>E</header></li>
</ul>
function addDnDHandlers(elem) {
elem.addEventListener('dragstart', handleDragStart, false); //拖拽元素开始被拖拽的时候触发的事件,此事件作用在被拖曳元素上
elem.addEventListener('dragenter', handleDragEnter, false) //当拖曳元素进入目标元素的时候触发的事件,此事件作用在目标元素上
elem.addEventListener('dragover', handleDragOver, false); //拖拽元素在目标元素上移动的时候触发的事件,此事件作用在目标元素上
elem.addEventListener('dragleave', handleDragLeave, false); //拖拽元素离开目标元素上移动的时候触发的事件,此事件作用在目标元素上
elem.addEventListener('drop', handleDrop, false); //被拖拽的元素在目标元素上同时鼠标放开触发的事件,此事件作用在目标元素上
elem.addEventListener('dragend', handleDragEnd, false); //当拖拽完成后触发的事件,此事件作用在被拖曳元素上
}
var cols = document.querySelectorAll('#columns .column');
[].forEach.call(cols, addDnDHandlers); //为每个元素绑定drop事件
function handleDragStart(e) {
// Target (this) element is the source node.
dragSrcEl = this;
//设置拖拽效果
e.dataTransfer.effectAllowed = 'move';
e.dataTransfer.setData('text/html', this.outerHTML);
//被拖拽的元素添加class
this.classList.add('dragElem');
}
function handleDragEnter(e) {
// this / e.target is the current hover target.
}
function handleDragOver(e) {
if (e.preventDefault) {
e.preventDefault(); // Necessary. Allows us to drop.
}
this.classList.add('over');
e.dataTransfer.dropEffect = 'move'; // See the section on the DataTransfer object.
return false;
}
function handleDragLeave(e) {
this.classList.remove('over'); // this / e.target is previous target element.
}
在拖拽过程中蓝色的线条是一个边框,利用拖拽事件添加class 并设置css就能有“响应”式的效果。
拖拽释放,进行html的替换。
function handleDrop(e) {
// this/e.target is current target element.
if (e.stopPropagation) {
e.stopPropagation(); // Stops some browsers from redirecting.
}
// Don't do anything if dropping the same column we're dragging.
if (dragSrcEl != this) {
// Set the source column's HTML to the HTML of the column we dropped on.
//alert(this.outerHTML);
//dragSrcEl.innerHTML = this.innerHTML;
//this.innerHTML = e.dataTransfer.getData('text/html');
this.parentNode.removeChild(dragSrcEl);
var dropHTML = e.dataTransfer.getData('text/html');
this.insertAdjacentHTML('beforebegin',dropHTML);
var dropElem = this.previousSibling;
addDnDHandlers(dropElem);
}
this.classList.remove('over');
return false;
}
function handleDragEnd(e) {
// this/e.target is the source node.
this.classList.remove('over');
/*[].forEach.call(cols, function (col) {
col.classList.remove('over');
});*/
}