1、基本思路javascript
一、先看最終的效果圖:css
二、實現原理:經過position:absolute(絕對定位)來定位每個元素的位置,而且將當前列的高度記錄下來方便下一個dom位置的計算html
2、代碼實現java
一、版本一:根據思路實現基礎版數組
<!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>css佈局-瀑布流的實現</title> <style type="text/css"> .box { position: relative; width: 500px; min-height: 100px; margin: 100px auto; background: #eeeeee; } .item { position: absolute; width: 120px; left: 0; top: 0; } </style> </head> <body> <div class="box"> <div class="item" style="height: 40px;background: red;"></div> <div class="item" style="height: 50px;background: blue;"></div> <div class="item" style="height: 100px;background: green;"></div> <div class="item" style="height: 60px;background: gray;"></div> <div class="item" style="height: 50px;background: orange;"></div> <div class="item" style="height: 20px;background: yellow;"></div> <div class="item" style="height: 40px;background: red;"></div> <div class="item" style="height: 50px;background: blue;"></div> <div class="item" style="height: 100px;background: green;"></div> <div class="item" style="height: 120px;background: gray;"></div> <div class="item" style="height: 58px;background: orange;"></div> <div class="item" style="height: 36px;background: yellow;"></div> </div> <script type="text/javascript"> const BOX_WIDTH = document.querySelector('.box').offsetWidth //瀑布流外層盒子的寬度 const ITEM_WIDTH = document.querySelector('.item').offsetWidth //瀑布流內層盒子的寬度 const COLUMN = Math.floor(BOX_WIDTH/ITEM_WIDTH) //根據寬度計算可渲染的列數 const MARGIN = (BOX_WIDTH - ITEM_WIDTH*COLUMN)/(COLUMN-1) // 根據寬度計算每一列的間距 const MARGINTOP = 10 //固定設置每個小盒子上下間距是10 let height_arr = new Array(COLUMN).fill(0) //定義一個長度等同與列數的數組用來存儲每一列的高度,初始值均爲0 let item = document.querySelectorAll('.item')
//遍歷每個小盒子,肯定小盒子的位置 for(let i = 0; i < item.length; i++) { let index = height_arr.indexOf(Math.min.apply(null, height_arr)) item[i].style.left = (ITEM_WIDTH + MARGIN) * index + 'px' item[i].style.top = height_arr[index] + MARGINTOP + 'px' height_arr[index] += item[i].offsetHeight + MARGINTOP }
//將數組中最大的值,即最高的那一列的高度賦給外層盒子 document.querySelector('.box').style.height = Math.max.apply(null, height_arr) + 'px' </script> </body> </html>
二、版本二:對版本一進行封裝,方便重複使用app
<!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>css佈局-瀑布流的實現</title> <style type="text/css"> .box { position: relative; width: 500px; min-height: 100px; margin: 100px auto; background: #eeeeee; } .item { position: absolute; width: 120px; left: 0; top: 0; } </style> </head> <body> <div class="box" style=""> <div class="item" style="height: 40px;background: red;"></div> <div class="item" style="height: 50px;background: blue;"></div> <div class="item" style="height: 100px;background: green;"></div> <div class="item" style="height: 60px;background: gray;"></div> <div class="item" style="height: 50px;background: orange;"></div> <div class="item" style="height: 20px;background: yellow;"></div> <div class="item" style="height: 40px;background: red;"></div> <div class="item" style="height: 50px;background: blue;"></div> <div class="item" style="height: 100px;background: green;"></div> <div class="item" style="height: 120px;background: gray;"></div> <div class="item" style="height: 58px;background: orange;"></div> <div class="item" style="height: 36px;background: yellow;"></div> </div> <script type="text/javascript"> function WaterFall(params) { this.box = (params && params.parent) || '.box' this.item = (params && params.child) || '.item' this.column = (params && params.column) || 0 this.row_margin = (params && params.row_margin) || 0 this.column_margin = (params && params.column_margin) || 10 this.height_arr = [] this._box_width = 0 this._item_width = 0 this._computed = function() { this._box_width = document.querySelector(this.box).offsetWidth this._item_width = document.querySelector(this.item).offsetWidth this.column = Math.floor((this._box_width - this.row_margin)/this._item_width) //列數 this.row_margin = !this.row_margin ? (this._box_width - this._item_width * this.column)/(this.column-1) : this.row_margin } this.init = function() { this._computed() let item = document.querySelectorAll(this.item) this.height_arr = new Array(this.column).fill(0) for(let i = 0; i < item.length; i++) { let index = this.height_arr.indexOf(Math.min.apply(null, this.height_arr)) item[i].style.left = (this._item_width + this.row_margin) * index + 'px' item[i].style.top = this.height_arr[index] + this.column_margin + 'px' this.height_arr[index] += item[i].offsetHeight + this.column_margin } document.querySelector('.box').style.height = Math.max.apply(null, this.height_arr) + 'px' } } var test = new WaterFall() test.init() </script> </body> </html>
3、總結:瀑布流的實現並不複雜,只要清楚了原理剩下的就是耐心的計算間距以及小盒子的位置啦~dom