效果截图
TL;DR
太长不看,直接看代码 👇
前言
五六年前就在 Typecho 上折腾过热力图,以前用 jQuery 折腾挺方便的。
但期间有些博客主题中没有合适的地方放热力图,就放弃了。
最近博客热力图又有热度了,刚好我这个主题可以放在首页,又折腾上了。
期间尝试了几个版本,网上也有非常多类似的库:
- ECharts.js
- Heat.js (没上线就放弃了)
- contributions-calendar
- d3.js + Cal-Heatmap.js
优缺点:
- ECharts.js 不方便控制细节,不方便适配移动端,资源文件比较大;
- Heat.js 在测试的时候发现了 Cal-Heatmap.js 了;
- Cal-Heatmap.js 是专门做热力图的,但需要引用多个库和插件。
从 Koobai 大佬发布《 HUGO 折腾随记之热力图 / 段落导航》时,我就说要折腾一个纯 CSS 版的热力图,一直推迟到今天才完成。期间折腾 Twitter Year Progress 时,完成了绘制年度日历小方块,直接用上了。
一、JS 构建热力图
1. 准备博客数据
在 Hugo 构建时,获取最近一年的文章数据:
// 获取最近一年的文章数据
{{ $pages := where .Site.RegularPages "Date" ">" (now.AddDate -1 0 0) }}
{{ $pages := $pages.Reverse }}
var blogInfo = {
"pages": [
{{ range $index, $element := $pages }}
{
"title": "{{ replace (replace .Title "《" "〈") "》" "〉" }}",
"date": "{{ .Date.Format "2006-01-02" }}",
"year": "{{ .Date.Format "2006" }}",
"month": "{{ .Date.Format "01" }}",
"day": "{{ .Date.Format "02" }}",
"word_count": "{{ .WordCount }}"
}{{ if ne (add $index 1) (len $pages) }},{{ end }}
{{ end }}
]
};
// console.log(blogInfo)
这段 JS 会获取到如下示例数据,并存入 blogInfo
中,如果需要 slug
、summary
或其他数据,按上面的代码依样画葫芦:
{
"pages": [
{
"title": "CSS 和 JS 实现博客热力图",
"date": "2024-04-30",
"year": "2024",
"month": "04",
"day": "30",
"word_count": "685"
}
]
}
2. 渲染月份
let monthNames = ['Jan', 'Feb', 'Mar']
中显示的月份数可以自定义。适配了移动端,常规移动设备显示 6 个月的数据,对于过小的设备,如:iPhone SE / Pixel 4 只显示 5 个月的数据。
let currentDate = new Date();
currentDate.setFullYear(currentDate.getFullYear() - 1);
let startDate;
let monthDiv = document.querySelector('.month');
let monthNames = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'];
if (window.innerWidth <= 375 ) { // iPhone SE
numMonths = 5;
} else if (window.innerWidth < 768 ) { // iPad Mini
numMonths = 6;
} else {
numMonths = 12;
}
let startMonthIndex = (currentDate.getMonth() - (numMonths - 1) + 12) % 12;
for (let i = startMonthIndex; i < startMonthIndex + numMonths; i++) {
let monthSpan = document.createElement('span');
let monthIndex = i % 12;
monthSpan.textContent = monthNames[monthIndex];
monthDiv.appendChild(monthSpan);
}
动态生成的月份显示在 <div class="month">
中,所以不管是 TailwindCSS 还是传统 CSS,month
这个 class 不能去掉。
<div class="month heatmap_month"> <!-- 👈 必须要有 [month] -->
<span>Nov</span>
<span>Dec</span>
<span>Jan</span>
<span>Feb</span>
<span>Mar</span>
<span>Apr</span>
</div>
3. startDate 之:起始日期从星期一开始渲染
如果单纯地从今天往前渲染 52 个周(一年)的小方块,很简单。不过这样渲染的数据有一个不符合常识的问题,即一年前的今天,并不一定是 星期一
,所以在选择热力图的开始日期的时候,需要考虑以 去年今天
所在星期的 星期一
作为起始点。
function getWeekDay(date) {
const day = date.getDay();
return day === 0 ? 6 : day - 1;
}
4. endDate 之:如果结束日期 今天
超出日历范围
结合第 3 点,如果 今天
的星期数比 去年今天
的星期数小,则会导致渲染 52 个周(一年)的小方块之后,今天
及今天之后的本周
内容渲染不了了,所以需要判断今天的星期数,并追加到年度日历小方块中。
const startDate = getStartDate();
const endDate = new Date();
const weekDay = getWeekDay(startDate);
let currentWeek = createWeek();
container.appendChild(currentWeek);
let currentDate = startDate;
let i = 0;
while (currentDate <= endDate) {
if (i % 7 === 0 && i !== 0) {
currentWeek = createWeek();
container.appendChild(currentWeek);
}
i++;
currentDate.setDate(currentDate.getDate() + 1);
}
5. 渲染小方块及 Tooltip
每个小方块以 count
字数显示不同色深的色块,即 CSS heatmap_day_level_num
的样式,count
按 1-1000
1000-2000
2000-3000
3000+
分为 4 个 level 截断。
我的博客中还渲染了 count
post
title
date
4 数据用于 Tooltip。
count
data-count 当天文章字数,多篇文章会合并计算post
data-post 当天文章数量title
data-title 当天文章的标题date
data-date 当天的日期Jan 2, 2006
en-US 格式
当鼠标经过小方块时,以 data-title=""
data-count=""
data-post=""
data-date=""
几个属性的值创建一个当日的 <div class="tooltip">
标签。
function createDay(date, title, count, post) {
const day = document.createElement("div");
day.className = "heatmap_day";
day.setAttribute("data-title", title);
day.setAttribute("data-count", count);
day.setAttribute("data-post", post);
day.setAttribute("data-date", date);
day.addEventListener("mouseenter", function () {
const tooltip = document.createElement("div");
tooltip.className = "heatmap_tooltip";
let tooltipContent = "";
if (post && parseInt(post, 10) !== 0) {
tooltipContent += '<span class="heatmap_tooltip_post">' + '共 ' + post + ' 篇' + '</span>';
}
if (count && parseInt(count, 10) !== 0) {
tooltipContent += '<span class="heatmap_tooltip_count">' + ' ' + count + ' 字;' + '</span>';
}
if (title && parseInt(title, 10) !== 0) {
tooltipContent += '<span class="heatmap_tooltip_title">' + title + '</span>';
}
if (date) {
tooltipContent += '<span class="heatmap_tooltip_date">' + date + '</span>';
}
tooltip.innerHTML = tooltipContent;
day.appendChild(tooltip);
});
day.addEventListener("mouseleave", function () {
const tooltip = day.querySelector(".heatmap_tooltip");
if (tooltip) {
day.removeChild(tooltip);
}
});
if (count == 0) {
day.classList.add("heatmap_day_level_0");
} else if (count > 0 && count < 1000) {
day.classList.add("heatmap_day_level_1");
} else if (count >= 1000 && count < 2000) {
day.classList.add("heatmap_day_level_2");
} else if (count >= 2000 && count < 3000) {
day.classList.add("heatmap_day_level_3");
} else {
day.classList.add("heatmap_day_level_4");
}
return day;
}
二、完整的 heatmap.js
前面的分解是只一些需要注意的细节,下面是完整的 JS:
// 获取最近一年的文章数据
{{ $pages := where .Site.RegularPages "Date" ">" (now.AddDate -1 0 0) }}
{{ $pages := $pages.Reverse }}
var blogInfo = {
"pages": [
{{ range $index, $element := $pages }}
{
"title": "{{ replace (replace .Title "《" "〈") "》" "〉" }}",
"date": "{{ .Date.Format "2006-01-02" }}",
"year": "{{ .Date.Format "2006" }}",
"month": "{{ .Date.Format "01" }}",
"day": "{{ .Date.Format "02" }}",
"word_count": "{{ .WordCount }}"
}{{ if ne (add $index 1) (len $pages) }},{{ end }}
{{ end }}
]
};
// console.log(blogInfo)
let currentDate = new Date();
currentDate.setFullYear(currentDate.getFullYear() - 1);
let startDate;
let monthDiv = document.querySelector('.month');
let monthNames = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'];
if (window.innerWidth < 768) {
numMonths = 6;
} else {
numMonths = 12;
}
let startMonthIndex = (currentDate.getMonth() - (numMonths - 1) + 12) % 12;
for (let i = startMonthIndex; i < startMonthIndex + numMonths; i++) {
let monthSpan = document.createElement('span');
let monthIndex = i % 12;
monthSpan.textContent = monthNames[monthIndex];
monthDiv.appendChild(monthSpan);
}
function getStartDate() {
const today = new Date();
if (window.innerWidth < 768) {
numMonths = 6;
} else {
numMonths = 12;
}
const startDate = new Date(today.getFullYear(), today.getMonth() - numMonths + 1, 1, today.getHours(), today.getMinutes(), today.getSeconds());
while (startDate.getDay() !== 1) {
startDate.setDate(startDate.getDate() + 1);
}
return startDate;
}
function getWeekDay(date) {
const day = date.getDay();
return day === 0 ? 6 : day - 1;
}
function createDay(date, title, count, post) {
const day = document.createElement("div");
day.className = "heatmap_day";
day.setAttribute("data-title", title);
day.setAttribute("data-count", count);
day.setAttribute("data-post", post);
day.setAttribute("data-date", date);
day.addEventListener("mouseenter", function () {
const tooltip = document.createElement("div");
tooltip.className = "heatmap_tooltip";
let tooltipContent = "";
if (post && parseInt(post, 10) !== 0) {
tooltipContent += '<span class="heatmap_tooltip_post">' + '共 ' + post + ' 篇' + '</span>';
}
if (count && parseInt(count, 10) !== 0) {
tooltipContent += '<span class="heatmap_tooltip_count">' + ' ' + count + ' 字;' + '</span>';
}
if (title && parseInt(title, 10) !== 0) {
tooltipContent += '<span class="heatmap_tooltip_title">《' + title + '》</span>';
}
if (date) {
tooltipContent += '<span class="heatmap_tooltip_date">' + date + '</span>';
}
tooltip.innerHTML = tooltipContent;
day.appendChild(tooltip);
});
day.addEventListener("mouseleave", function () {
const tooltip = day.querySelector(".heatmap_tooltip");
if (tooltip) {
day.removeChild(tooltip);
}
});
if (count == 0 ) {
day.classList.add("heatmap_day_level_0");
} else if (count > 0 && count < 1000) {
day.classList.add("heatmap_day_level_1");
} else if (count >= 1000 && count < 2000) {
day.classList.add("heatmap_day_level_2");
} else if (count >= 2000 && count < 3000) {
day.classList.add("heatmap_day_level_3");
} else {
day.classList.add("heatmap_day_level_4");
}
return day;
}
function createWeek() {
const week = document.createElement('div');
week.className = 'heatmap_week';
return week;
}
function createHeatmap() {
const container = document.getElementById('heatmap');
const startDate = getStartDate();
const endDate = new Date();
const weekDay = getWeekDay(startDate);
let currentWeek = createWeek();
container.appendChild(currentWeek);
let currentDate = startDate;
let i = 0;
while (currentDate <= endDate) {
if (i % 7 === 0 && i !== 0) {
currentWeek = createWeek();
container.appendChild(currentWeek);
}
const dateString = `${currentDate.getFullYear()}-${("0" + (currentDate.getMonth()+1)).slice(-2)}-${("0" + (currentDate.getDate())).slice(-2)}`;
const articleDataList = blogInfo.pages.filter(page => page.date === dateString);
if (articleDataList.length > 0) {
const titles = articleDataList.map(data => data.title);
const title = titles.map(t => `${t}`).join('<br />');
let count = 0;
let post = articleDataList.length;
articleDataList.forEach(data => {
count += parseInt(data.word_count, 10);
});
const formattedDate = formatDate(currentDate);
const day = createDay(formattedDate, title, count, post);
currentWeek.appendChild(day);
} else {
const formattedDate = formatDate(currentDate);
const day = createDay(formattedDate, '', '0', '0');
currentWeek.appendChild(day);
}
i++;
currentDate.setDate(currentDate.getDate() + 1);
}
}
function formatDate(date) {
const options = { month: 'short', day: 'numeric', year: 'numeric' };
return date.toLocaleDateString('en-US', options);
}
createHeatmap();
三、HTML DIV 容器
准备 HTML 容器,用于渲染 Heatmap,我博客用的是 TailwindCSS,为了写文章,已转成传统 CSS 样式,相当于用 CSS 重新实现了一遍。
全部使用 Flex 排版,为了适配移动端,用 JS 检测屏幕宽度动态生成月份和年度日历小方块。做了 2 个截断,一是个 iPhone SE 的 375 宽度和 iPad Mini 的 768 宽度,宽度截断在后面的 JS 中可以看到。
<div class="heatmap_container"> <!-- 全部用 Flex 排版 -->
<div class="heatmap_content">
<div class="heatmap_week">
<span>Mon</span>
<span> </span> <!-- 不需要显示的星期用空格表示 -->
<span>Wed</span>
<span> </span>
<span>Fri</span>
<span> </span>
<span>Sun</span>
</div>
<div class="heatmap_main">
<div class="month heatmap_month">
<!-- js 检测屏幕宽度动态生成月份 -->
</div>
<div id="heatmap" class="heatmap">
<!-- js 检测屏幕宽度动态生成年度日历小方块 -->
</div>
</div>
</div>
<div class="heatmap_footer">
<div class="heatmap_less">Less</div>
<div class="heatmap_level">
<span class="heatmap_level_item heatmap_level_0"></span>
<span class="heatmap_level_item heatmap_level_1"></span>
<span class="heatmap_level_item heatmap_level_2"></span>
<span class="heatmap_level_item heatmap_level_3"></span>
<span class="heatmap_level_item heatmap_level_4"></span>
</div>
<div class="heatmap_more">More</div>
</div>
</div>
四、传统 style.css
CSS 样式仿照的是 GitHub 的配色,Dark mode 是 GitHub Dimmed 的配色。
:root {
/* GitHub Light Color */
--ht-main: #334155;
--ht-day-bg: #ebedf0;
--ht-tooltip: #24292f;
--ht-tooltip-bg: #fff;
--ht-lv-0: #ebedf0;
--ht-lv-1: #9be9a8;
--ht-lv-2: #40c463;
--ht-lv-3: #30a14e;
--ht-lv-4: #216e39;
}
[data-theme="dark"] {
/* GitHub Dark Dimmed Color */
--ht-main: #94a3b8;
--ht-day-bg: #161b22;
--ht-tooltip: #24292f;
--ht-tooltip-bg: #fff;
--ht-lv-0: #161b22;
--ht-lv-1: #0e4429;
--ht-lv-2: #006d32;
--ht-lv-3: #26a641;
--ht-lv-4: #39d353;
}
.heatmap_container {
display: flex;
flex-direction: column;
align-items: flex-end;
font-size: 10px;
line-height: 12px;
color: var(--ht-main);
}
.heatmap_content {
display: flex;
flex-direction: row;
align-items: flex-end
}
.heatmap_week {
display: flex;
margin-top: 0.25rem;
margin-right: 0.25rem;
flex-direction: column;
justify-content: flex-end;
align-items: flex-end;
text-align: right
}
.heatmap_main {
display: flex;
flex-direction: column
}
.heatmap_month {
display: flex;
margin-top: 0.25rem;
margin-right: 0.25rem;
flex-direction: column;
justify-content: space-around;
align-items: flex-end;
text-align: right;
}
.heatmap {
display: flex;
flex-direction: row;
height: 84px;
}
.heatmap_footer {
display: flex;
margin-top: 0.5rem;
align-items: center
}
.heatmap_level {
display: flex;
gap: 2px;
margin: 0 0.25rem;
flex-direction: row;
align-items: center;
width: max-content;
height: 10px
}
.heatmap_level_item {
display: block;
border-radius: 0.125rem;
width: 10px;
height: 10px;
}
.heatmap_level_0 {
background: var(--ht-lv-0);
}
.heatmap_level_1 {
background: var(--ht-lv-1);
}
.heatmap_level_2 {
background: var(--ht-lv-2);
}
.heatmap_level_3 {
background: var(--ht-lv-3);
}
.heatmap_level_4 {
background: var(--ht-lv-4);
}
.heatmap_week {
display: flex;
flex-direction: column;
}
.heatmap_day {
width: 10px;
height: 10px;
background-color: var(--ht-day-bg);
margin: 1px;
border-radius: 2px;
display: inline-block;
position: relative;
}
.heatmap_tooltip {
position: absolute;
bottom: 12px;
left: 50%;
width: max-content;
color: var(--ht-tooltip);
background-color: var(--ht-tooltip-bg);
font-size: 12px;
line-height: 16px;
padding: 8px;
border-radius: 3px;
white-space: pre-wrap;
opacity: 1;
transition: 0.3s;
z-index: 1000;
text-align: right;
transform: translateX(-50%);
}
.heatmap_tooltip_count,
.heatmap_tooltip_post {
display: inline-block;
}
.heatmap_tooltip_title,
.heatmap_tooltip_date {
display: block;
}
.heatmap_tooltip_date {
margin: 0 0.25rem;
}
.heatmap_day_level_0 {
background-color: var(--ht-lv-0);
}
.heatmap_day_level_1 {
background-color: var(--ht-lv-1);
}
.heatmap_day_level_2 {
background-color: var(--ht-lv-2);
}
.heatmap_day_level_3 {
background-color: var(--ht-lv-3);
}
.heatmap_day_level_4 {
background-color: var(--ht-lv-4);
}
五、TailwindCSS 样式
<div class="flex flex-col items-end text-[10px] leading-[12px] text-neutral-700 dark:text-neutral-400">
<div class="flex flex-row items-end">
<div class="flex flex-col justify-end items-end mr-1 mt-1 text-right">
<span>Mon</span>
<span> </span>
<span>Wed</span>
<span> </span>
<span>Fri</span>
<span> </span>
<span>Sun</span>
</div>
<div class="heatmap flex flex-col">
<div class="month mb-1 flex justify-around">
</div>
<div class="h-[84px]">
<div id="heatmap" class="flex flex-row"></div>
</div>
</div>
</div>
<div class="flex mt-2 items-center">
<span class="">Less</span>
<div class="flex flex-row items-center gap-[2px] w-max h-[10px] mx-1">
<span class="block w-[10px] h-[10px] rounded-sm bg-[#ebedf0] dark:bg-[#161b22]"></span>
<span class="block w-[10px] h-[10px] rounded-sm bg-[#9be9a8] dark:bg-[#0e4429]"></span>
<span class="block w-[10px] h-[10px] rounded-sm bg-[#40c463] dark:bg-[#006d32]"></span>
<span class="block w-[10px] h-[10px] rounded-sm bg-[#30a14e] dark:bg-[#26a641]"></span>
<span class="block w-[10px] h-[10px] rounded-sm bg-[#216e39] dark:bg-[#39d353]"></span>
</div>
<span class="">More</span>
</div>
</div>