极简天气
一款简单的chrome天气插件。
github https://github.com/yohnz/weather
如图：
1.png
创建文件
新建weather文件夹，里面包含manifest.json，popup.html和images文件夹。images文件夹放16,48,128三种不同尺寸的图标
manifest.json内代码如下：
{
"manifest_version":2,
"name":"极简天气",
"description":"极简天气预报",
"version":"1.0",
"icons": {
"16": "images/sun16.png",
"48": "images/sun48.png",
"128": "images/sun128.png"
},
"browser_action":{
"default_icon":"images/sun48.png",
"default_title":"天气预报",
"default_popup":"popup.html"
},
}
popup.html的代码如下：
<!DOCTYPE html>
<html lang="zh">
<head>
<meta charset="UTF-8">
<title>天气</title>
</head>
<body>
<div class="weather">
Test
</div>
</body>
</html>
文件说明
manifest.json
必需文件，是整个扩展的入口，每个Chrome扩展都包含一个Manifest文件。Manifest必须包含name、version和manifest_version属性。
属性说明：
-
manifest_version指定文件格式的版本，在Chrome18之后，应该都是2 -
name扩展名称 -
version扩展版本号 -
version扩展的版本 -
icons扩展列表图标 -
browser_action指定扩展在Chrome工具栏中的显示信息。 -
default_icon、default_title、default_popup依次指定图标、标题、对应的页面
Popup页面
Popup页面是当用户点击扩展图标时，展示在图标下面的页面。
打开chrome扩展程序界面，勾选"开发者模式",拖入weather文件夹，然后就可以看到weather扩展已经出现在chrome扩展程序列表了
1.jpg
同时，工具栏也出现了weather的图标，点击之后会弹出popup界面:
2.jpg
完善页面和样式
完善静态popup页面,模拟天气数据:
<!DOCTYPE html>
<html lang="zh">
<head>
<meta charset="UTF-8">
<title>天气</title>
</head>
<body>
<div class="weather">
<div class="today" id="today">
<h1 class="city">厦门</h1>
<div class="row_detail">
<h1>19<span>℃</span></h1></div>
<div class="wind">
<h2>阴</h2>
<h4>风速 20 湿度 89%</h4></div>
</div>
<div class="content">
<div class="wrap" id="wrap">
<div class="row">
<h4>2016-05-16</h4>
<h1>19~24</h1>
<h4>阴</h4>
</div>
</div>
</div>
</div>
</body>
</html>
新建CSS文件，并在popup页面引入
body{
width:740px;
height:400px;
font-family: 'Microsoft Yahei';
color:#333;
background:#fefefe;
text-shadow:1px 1px 6px #333;
}
.city{
text-align:center
}
.today{
padding-bottom:30px;
}
.row_detail{
display: flex;
direction: row;
justify-content:center;
align-items: center;
}
.row_detail img{
width:80px;
}
.row_detail h1{
font-size:60px;
}
.wind{
text-align: center;
}
.content{
display: flex;
direction: column
}
.wrap{
display: flex;
direction: row;
flex: 1;
justify-content:space-around;
align-items: center;
}
.row{
background:#fff;
border:1px solid #ccc;
padding:10px;
box-shadow: 0 2px 10px rgba(0,0,0,.3);
}
.row img{
width:80px;
}
.row h1{
font-size:18px;
}
h1,h4{
text-align: center;
margin:0;
}
点击工具栏weather图标，此时界面如图：
3.jpg
获取真实天气数据
Google允许Chrome扩展应用不必受限于跨域限制。但出于安全考虑，需要在Manifest的permissions属性中声明需要跨域的权限。
这里以和风天气API为例.
首先，在Manifest里添加要请求的API接口：
"permissions":[
"http://api.openweathermap.org/data/2.5/forecast?q=*",
]
然后新建popup.js并在popup页面中引入
简单的ajax函数：
function httpRequest(url,callback) {
var xhr = new XMLHttpRequest();
xhr.open('GET',url,true);
xhr.onreadystatechange = function() {
if(xhr.readyState === 4){
callback(xhr.responseText);
}
}
xhr.send();
}
和风天气API可以通过城市名称，城市代码,IP三种方式来获取指定城市天气数据，不过经过测试发现，IP获取的方式不准确，城市有偏差，所以，直接用城市名称来获取。这里借用http://int.dpool.sina.com.cn/iplookup/iplookup.php?format=json获取城市名称。
httpRequest('http://int.dpool.sina.com.cn/iplookup/iplookup.php?format=json',function(data) {
if(!data) return;
data = JSON.parse(data);
var city = data.city;
var url = 'https://api.heweather.com/x3/weather?city='+city+'&key=youkey';
httpRequest(url,function(data) {
data = JSON.parse(data);
var result = data["HeWeather data service 3.0"][0];
showWeather(city,result);
});
});
为了方便的解析图片，构建一个json
var cond_info = {
100:"http://files.heweather.com/cond_icon/100.png",
101:"http://files.heweather.com/cond_icon/101.png",
102:"http://files.heweather.com/cond_icon/102.png",
103:"http://files.heweather.com/cond_icon/103.png",
104:"http://files.heweather.com/cond_icon/104.png",
200:"http://files.heweather.com/cond_icon/200.png",
201:"http://files.heweather.com/cond_icon/201.png",
202:"http://files.heweather.com/cond_icon/202.png",
203:"http://files.heweather.com/cond_icon/203.png",
204:"http://files.heweather.com/cond_icon/204.png",
205:"http://files.heweather.com/cond_icon/205.png",
206:"http://files.heweather.com/cond_icon/206.png",
207:"http://files.heweather.com/cond_icon/207.png",
208:"http://files.heweather.com/cond_icon/208.png",
209:"http://files.heweather.com/cond_icon/209.png",
210:"http://files.heweather.com/cond_icon/210.png",
211:"http://files.heweather.com/cond_icon/211.png",
212:"http://files.heweather.com/cond_icon/212.png",
213:"http://files.heweather.com/cond_icon/213.png",
300:"http://files.heweather.com/cond_icon/300.png",
301:"http://files.heweather.com/cond_icon/301.png",
302:"http://files.heweather.com/cond_icon/302.png",
303:"http://files.heweather.com/cond_icon/303.png",
304:"http://files.heweather.com/cond_icon/304.png",
305:"http://files.heweather.com/cond_icon/305.png",
306:"http://files.heweather.com/cond_icon/306.png",
307:"http://files.heweather.com/cond_icon/307.png",
308:"http://files.heweather.com/cond_icon/308.png",
309:"http://files.heweather.com/cond_icon/309.png",
310:"http://files.heweather.com/cond_icon/310.png",
311:"http://files.heweather.com/cond_icon/311.png",
312:"http://files.heweather.com/cond_icon/312.png",
313:"http://files.heweather.com/cond_icon/313.png",
400:"http://files.heweather.com/cond_icon/400.png",
401:"http://files.heweather.com/cond_icon/401.png",
402:"http://files.heweather.com/cond_icon/402.png",
403:"http://files.heweather.com/cond_icon/403.png",
404:"http://files.heweather.com/cond_icon/404.png",
405:"http://files.heweather.com/cond_icon/405.png",
406:"http://files.heweather.com/cond_icon/406.png",
407:"http://files.heweather.com/cond_icon/407.png",
500:"http://files.heweather.com/cond_icon/500.png",
501:"http://files.heweather.com/cond_icon/501.png",
502:"http://files.heweather.com/cond_icon/502.png",
503:"http://files.heweather.com/cond_icon/503.png",
504:"http://files.heweather.com/cond_icon/504.png",
506:"http://files.heweather.com/cond_icon/506.png",
507:"http://files.heweather.com/cond_icon/507.png",
508:"http://files.heweather.com/cond_icon/508.png",
900:"http://files.heweather.com/cond_icon/900.png",
901:"http://files.heweather.com/cond_icon/901.png",
999:"http://files.heweather.com/cond_icon/999.png"
}
showWeather()函数构建DOM;
function showWeather(city,result) {
var daily = result.daily_forecast;
var now = result.now;
var dailyDom='';
for(var i=0;i<daily.length;i++){
var day = daily[i];
dailyDom += '<div class="row">'
+'<h4>'+day.date+'</h4>'
+'[站外图片上传中……(3)]'
+'<h1>'+day.tmp.min+'~'+day.tmp.max+'</h1>'
+'<h4>'+day.cond.txt_d+'</h4>'
+'</div>'
}
var today = '<h1 class="city">'+city+'</h1>'
+'<div class="row_detail">'
+'[站外图片上传中……(4)]'
+'<h1>'+now.tmp+'<span>℃</span></h1>'
+'</div>'
+'<div class="wind">'
+'<h2>'+now.cond.txt+'</h2>'
+'<h4>风速 '+now.wind.spd+' 湿度 '+now.hum+'%</h4>'
+'</div>'
document.getElementById('today').innerHTML = today;
document.getElementById('wrap').innerHTML = dailyDom;
}
这时，再点击weather图标，天气扩展基本上就完成了，不过因为和风API有请求次数限制，也为了减少请求，这里做一下数据缓存。
var _time = new Date().getTime()-(60*60*1000*2); //接口次数有限，两小时请求一次
var storageTime = localStorage.updateTime||0;
httpRequest('http://int.dpool.sina.com.cn/iplookup/iplookup.php?format=json',function(data) {
if(!data) return;
data = JSON.parse(data);
var city = data.city;
var url = 'https://api.heweather.com/x3/weather?city='+city+'&key=youkey';
if(_time>storageTime){
httpRequest(url,function(data) {
data = JSON.parse(data);
var result = data["HeWeather data service 3.0"][0];
showWeather(city,result);
localStorage.updateTime = new Date().getTime();
localStorage.data = JSON.stringify(result);
});
}else{
var result = JSON.parse(localStorage.data);
showWeather(city,result);
}
});
至此，一个简单的chrome天气扩展就完成了，是不是比想象中更简单?如果觉得本文有帮助，请github赏个star~
