首先说下原理。
这种方法也可以做到整个页面始终只有2个img标签,而不必把所有的img节点全部创建出来,要点是每次更换不可见img的src。
动画的实现
这样就完成了一次移动的动画。
<header> <div class="box"> <img src="imgs/banner1.jpg"> <img src="imgs/banner2.jpg"> <img src="imgs/banner3.jpg"> <img src="imgs/banner4.jpg"> </div> <div class="buttons"> <div class="active">1</div> <div>2</div> <div>3</div> <div>4</div> </div> <div class="left"> <div class="arrow"></div> </div> <div class="right"> <div class="arrow"></div> </div> </header>
var timeout = null; window.onload = function () { var oLeft = document.querySelector('.left'); var oRight = document.querySelector('.right'); var oButton = document.querySelector('.buttons'); var oButtons = document.querySelectorAll('.buttons div'); var oImgs = document.querySelectorAll('.box img'); var imgWidth = oImgs[0].width; var gIndex = 0; begainAnimate(); // 绑定左右点击事件 oLeft.onclick = function () { clearTimeout(timeout); leftMove(); begainAnimate(); }; oRight.onclick = function () { clearTimeout(timeout); rightMove(); begainAnimate(); }; // 绑定数字序号事件 oButton.onclick = function (event) { clearTimeout(timeout); var targetEl = event.target; var nextIndex = (+targetEl.innerText) - 1; console.log(nextIndex); rightMove(nextIndex); begainAnimate(); } // 默认初始动画朝右边 function begainAnimate() { clearTimeout(timeout); timeout = setTimeout(function () { rightMove(); begainAnimate(); }, 3000); } // 向左移动动画 function leftMove() { var nextIndex = (gIndex - 1 < 0) ? oImgs.length - 1 : gIndex - 1; animateSteps(nextIndex, -50); } // 向右移动动画 function rightMove(nextIndex) { if (nextIndex == undefined) { nextIndex = (gIndex + 1 >= oImgs.length) ? 0 : gIndex + 1; } animateSteps(nextIndex, 50); } // 一次动画 function animateSteps(nextIndex, timestamp) { var currentImg = oImgs[gIndex]; var nextImg = oImgs[nextIndex]; nextImg.style.zIndex = 10; var step = 0; requestAnimationFrame(goStep); // 走一帧的动画,移动timestamp function goStep() { var moveWidth = timestamp * step++; if (Math.abs(moveWidth) < imgWidth) { currentImg.style.transform = `translate(${moveWidth}px)`; nextImg.style.transform = `translate(${moveWidth > 0 ? (moveWidth - imgWidth) : (imgWidth + moveWidth)}px)`; requestAnimationFrame(goStep); } else { currentImg.style.zIndex = 1; currentImg.style.transform = `translate(0px)`; nextImg.style.transform = `translate(0px)`; oButtons[gIndex].setAttribute('class', ''); oButtons[nextIndex].setAttribute('class', 'active'); gIndex = nextIndex; } } } } window.onclose = function () { clearTimeout(timeout); }
<style> /* 首先设置图片box的区域,将图片重叠在一起 */ header { width: 100%; position: relative; overflow: hidden; } .box { width: 100%; height: 300px; } .box img { width: 100%; height: 100%; position: absolute; transform: translateX(0); z-index: 1; } .box img:first-child { z-index: 10; } /* 数字序列按钮 */ .buttons { position: absolute; right: 10%; bottom: 5%; display: flex; z-index: 100; } .buttons div { width: 30px; height: 30px; background-color: #aaa; border: 1px solid #aaa; text-align: center; margin: 10px; cursor: pointer; opacity: .7; border-radius: 15px; line-height: 30px; } .buttons div.active { background-color: white; } /* 左右切换按钮 */ .left, .right { position: absolute; width: 80px; height: 80px; background-color: #ccc; z-index: 100; top: 110px; border-radius: 40px; opacity: .5; cursor: pointer; } .left { left: 2%; } .right { right: 2%; } .left .arrow { width: 30px; height: 30px; border-left: solid 5px #666; border-top: solid 5px #666; transform: translate(-5px, 25px) rotate(-45deg) translate(25px, 25px); } .right .arrow { width: 30px; height: 30px; border-left: solid 5px #666; border-top: solid 5px #666; transform: translate(50px, 25px) rotate(135deg) translate(25px, 25px); } </style>