這種效果能夠由元素內嵌套canves實現,也能夠由css3實現。css
Canves實現html
網上摘了一份canves實現的代碼,略微去掉了些重複定義的樣式而且給出js註釋,代碼以下css3
第一種方法:web
html骨架代碼canvas
<a class="btn color-1 material-design" data-color="#2f5398">Press me!</a>
css代碼app
* { box-sizing: border-box; outline: none; } body { font-family: 'Open Sans'; font-size: 100%; font-weight: 300; line-height: 1.5em; text-align: center; } .btn { border: none; display: inline-block; color: white; overflow: hidden; margin: 1rem; padding: 0; width: 150px; height: 40px; text-align: center; line-height: 40px; border-radius: 5px; } .btn.color-1 { background-color: #426fc5; } .btn-border.color-1 { background-color: transparent; border: 2px solid #426fc5; color: #426fc5; } .material-design { position: relative; } .material-design canvas { opacity: 0.25; position: absolute; top: 0; left: 0; } .container { align-content: center; align-items: flex-start; display: flex; flex-direction: row; flex-wrap: wrap; justify-content: center; margin: 0 auto; max-width: 46rem; }
js代碼flex
var canvas = {}, centerX = 0, centerY = 0, color = '', containers = document.getElementsByClassName('material-design') context = {}, element = {}, radius = 0, // 根據callback生成requestAnimationFrame動畫 requestAnimFrame = function () { return ( window.requestAnimationFrame || window.mozRequestAnimationFrame || window.oRequestAnimationFrame || window.msRequestAnimationFrame || function (callback) { window.setTimeout(callback, 1000 / 60); } ); } (), // 爲每一個指定元素生成canves init = function () { containers = Array.prototype.slice.call(containers); for (var i = 0; i < containers.length; i += 1) { canvas = document.createElement('canvas'); canvas.addEventListener('click', press, false); containers[i].appendChild(canvas); canvas.style.width ='100%'; canvas.style.height='100%'; canvas.width = canvas.offsetWidth; canvas.height = canvas.offsetHeight; } }, // 點擊而且獲取須要的數據,如點擊座標、元素大小、顏色 press = function (event) { color = event.toElement.parentElement.dataset.color; element = event.toElement; context = element.getContext('2d'); radius = 0; centerX = event.offsetX; centerY = event.offsetY; context.clearRect(0, 0, element.width, element.height); draw(); }, // 繪製圓形,而且執行動畫 draw = function () { context.beginPath(); context.arc(centerX, centerY, radius, 0, 2 * Math.PI, false); context.fillStyle = color; context.fill(); radius += 2; // 經過判斷半徑小於元素寬度,不斷繪製 radius += 2 的圓形 if (radius < element.width) { requestAnimFrame(draw); } }; init();
第二種方法:動畫
html代碼spa
<a class="waves ts-btn">Press me!</a>
cssprototype
.waves{ position:relative; cursor:pointer; display:inline-block; overflow:hidden; text-align: center; -webkit-tap-highlight-color:transparent; z-index:1; } .waves .waves-animation{ position:absolute; border-radius:50%; width:25px; height:25px; opacity:0; background:rgba(255,255,255,0.3); transition:all 0.7s ease-out; transition-property:transform, opacity, -webkit-transform; -webkit-transform:scale(0); transform:scale(0); pointer-events:none } .ts-btn{ width: 200px; height: 56px; line-height: 56px; background: #f57035; color: #fff; border-radius: 5px; }
js
document.addEventListener('DOMContentLoaded',function(){ var duration = 750; // 樣式string拼湊 var forStyle = function(position){ var cssStr = ''; for( var key in position){ if(position.hasOwnProperty(key)) cssStr += key+':'+position[key]+';'; }; return cssStr; } // 獲取鼠標點擊位置 var forRect = function(target){ var position = { top:0, left:0 }, ele = document.documentElement; 'undefined' != typeof target.getBoundingClientRect && (position = target.getBoundingClientRect()); return { top: position.top + window.pageYOffset - ele.clientTop, left: position.left + window.pageXOffset - ele.clientLeft } } var show = function(event){ var pDiv = event.target, cDiv = document.createElement('div'); pDiv.appendChild(cDiv); var rectObj = forRect(pDiv), _height = event.pageY - rectObj.top, _left = event.pageX - rectObj.left, _scale = 'scale(' + pDiv.clientWidth / 100 * 10 + ')'; var position = { top: _height+'px', left: _left+'px' }; cDiv.className = cDiv.className + " waves-animation", cDiv.setAttribute("style", forStyle(position)), position["-webkit-transform"] = _scale, position["-moz-transform"] = _scale, position["-ms-transform"] = _scale, position["-o-transform"] = _scale, position.transform = _scale, position.opacity = "1", position["-webkit-transition-duration"] = duration + "ms", position["-moz-transition-duration"] = duration + "ms", position["-o-transition-duration"] = duration + "ms", position["transition-duration"] = duration + "ms", position["-webkit-transition-timing-function"] = "cubic-bezier(0.250, 0.460, 0.450, 0.940)", position["-moz-transition-timing-function"] = "cubic-bezier(0.250, 0.460, 0.450, 0.940)", position["-o-transition-timing-function"] = "cubic-bezier(0.250, 0.460, 0.450, 0.940)", position["transition-timing-function"] = "cubic-bezier(0.250, 0.460, 0.450, 0.940)", cDiv.setAttribute("style", forStyle(position)); var finishStyle = { opacity: 0, "-webkit-transition-duration": duration + "ms", "-moz-transition-duration": duration + "ms", "-o-transition-duration": duration + "ms", "transition-duration": duration + "ms", "-webkit-transform" : _scale, "-moz-transform" : _scale, "-ms-transform" : _scale, "-o-transform" : _scale, top: _height + "px", left: _left + "px", }; setTimeout(function(){ cDiv.setAttribute("style", forStyle(finishStyle)); setTimeout(function(){ pDiv.removeChild(cDiv); },duration); },100) } document.querySelector('.waves').addEventListener('click',function(e){ show(e); },!1); },!1);