Canvas制作天气预报走势图

要实现的效果如下图:

HTML代码如下:

<!DOCTYPE html>
<html>
<head>
    <title></title>
    <link rel="stylesheet" type="text/css" href="common.css"/>
</head>
<body>
    <div class="weather-container">
        <canvas id="myCanvas" width="640" height="150"></canvas>
        <class="oneDayWeather pastDay" href="http://www.sinohuaxia.cn" target="_blank">
            <div class="weekDay">周二</div>
            <div class="curWeather">阵雨</div>
            <div class="curWeatherPic"></div>
            <div class="highTempNum" id="highTempNum0">32°</div>
            <div class="highTemp" id="highTemp0"></div>
            <div class="lowTemp" id="lowTemp0"></div>
            <div class="lowTempNum" id="lowTempNum0">20°</div>
            <div class="dayWeatherPic"></div>
            <div class="dayWeather">雷阵雨</div>
            <div class="dayDate">06/09</div>
        </a>
        <class="oneDayWeather pastDay" href="http://www.sinohuaxia.cn" target="_blank">
            <div class="weekDay">周二</div>
            <div class="curWeather">阵雨</div>
            <div class="curWeatherPic"></div>
            <div class="highTempNum" id="highTempNum1">29°</div>
            <div class="highTemp" id="highTemp1"></div>
            <div class="lowTemp" id="lowTemp1"></div>
            <div class="lowTempNum" id="lowTempNum1">24°</div>
            <div class="dayWeatherPic"></div>
            <div class="dayWeather">雷阵雨</div>
            <div class="dayDate">06/09</div>
        </a>
        <class="oneDayWeather" href="http://www.sinohuaxia.cn" target="_blank">
            <div class="weekDay">周二</div>
            <div class="curWeather">阵雨</div>
            <div class="curWeatherPic"></div>
            <div class="highTempNum" id="highTempNum2">32°</div>
            <div class="highTemp" id="highTemp2"></div>
            <div class="lowTemp" id="lowTemp2"></div>
            <div class="lowTempNum" id="lowTempNum2">22°</div>
            <div class="dayWeatherPic"></div>
            <div class="dayWeather">雷阵雨</div>
            <div class="dayDate">06/09</div>
        </a>
        <class="oneDayWeather" href="http://www.sinohuaxia.cn" target="_blank">
            <div class="weekDay">周二</div>
            <div class="curWeather">阵雨</div>
            <div class="curWeatherPic"></div>
            <div class="highTempNum" id="highTempNum3">28°</div>
            <div class="highTemp" id="highTemp3"></div>
            <div class="lowTemp" id="lowTemp3"></div>
            <div class="lowTempNum" id="lowTempNum3"></div>
            <div class="dayWeatherPic"></div>
            <div class="dayWeather">雷阵雨</div>
            <div class="dayDate">06/09</div>
        </a>
        <class="oneDayWeather" href="http://www.sinohuaxia.cn" target="_blank">
            <div class="weekDay">周二</div>
            <div class="curWeather">阵雨</div>
            <div class="curWeatherPic"></div>
            <div class="highTempNum" id="highTempNum4">31°</div>
            <div class="highTemp" id="highTemp4"></div>
            <div class="lowTemp" id="lowTemp4"></div>
            <div class="lowTempNum" id="lowTempNum4">20°</div>
            <div class="dayWeatherPic"></div>
            <div class="dayWeather">雷阵雨</div>
            <div class="dayDate">06/09</div>
        </a>
        <class="oneDayWeather" href="http://www.sinohuaxia.cn" target="_blank">
            <div class="weekDay">周二</div>
            <div class="curWeather">阵雨</div>
            <div class="curWeatherPic"></div>
            <div class="highTempNum" id="highTempNum5">28°</div>
            <div class="highTemp" id="highTemp5"></div>
            <div class="lowTemp" id="lowTemp5"></div>
            <div class="lowTempNum" id="lowTempNum5">12°</div>
            <div class="dayWeatherPic"></div>
            <div class="dayWeather">雷阵雨</div>
            <div class="dayDate">06/09</div>
        </a>
    </div>
    
    <script type="text/javascript">
    
var canvas=document.getElementById('myCanvas');
    
var canvasTop=canvas.offsetTop;
    
var ctx=canvas.getContext('2d');
    
var sixdayHighTemperature=[32,29,32,28,31,28];
    
var sixdayLowTemperature=[20,24,22,9,20,12];
    
var picHeight=150;
    
var maxHighTemp=maxNum(sixdayHighTemperature);
    
var minLowTemp=minNum(sixdayLowTemperature);
    
var maxRange=maxHighTemp-minLowTemp;
    
function maxNum(arr){
        
var maxNum=0;
        
if(arr.length){
            
for(var i=0,len=arr.length;i<len;i++){
                
if(i==0){
                    maxNum
=arr[0];
                }
else if(maxNum<arr[i]){
                    maxNum
=arr[i];
                }
            }
        }
        
return maxNum;
    }
    
function minNum(arr){
        
var minNum=0;
        
if(arr.length){
            
for(var i=0,len=arr.length;i<len;i++){
                
if(i==0){
                    minNum
=arr[0];
                }
else if(minNum>arr[i]){
                    minNum
=arr[i];
                }
            }
        }
        
return minNum;
    }
    ctx.strokeStyle
="#fff";
    ctx.lineWidth
=2;
    (
function drawHighTemp(temps){
            
var drawX=0,drawY=0;
            
var distance=Math.floor(picHeight/maxRange);
            for(var i=0,len=temps.length;i<len;i++){
                drawX
=i*106+53;
                drawY
=(maxHighTemp-temps[i])*distance;
                document.getElementById(
'highTemp'+i).style.top=(canvasTop+drawY-5)+"px";
                document.getElementById(
'highTempNum'+i).style.top=(canvasTop+drawY-25)+"px";
                
if(i==0){
                    ctx.moveTo(drawX,drawY);
                }
else{
                    ctx.lineTo(drawX,drawY);
                }
            }
            ctx.stroke();
        })(sixdayHighTemperature);
        (
function drawHighTemp(temps){
            
var drawX=0,drawY=0;
            
var distance=Math.floor(picHeight/maxRange);
            for(var i=0,len=temps.length;i<len;i++){
                drawX
=i*106+53;
                drawY
=picHeight-((temps[i]-minLowTemp)*distance);
                document.getElementById(
'lowTemp'+i).style.top=(canvasTop+drawY-5)+"px";
                document.getElementById(
'lowTempNum'+i).style.top=(canvasTop+drawY+10)+"px";
                
if(i==0){
                    ctx.moveTo(drawX,drawY);
                }
else{
                    ctx.lineTo(drawX,drawY);
                }
            }
            ctx.stroke();
        })(sixdayLowTemperature)
    
    
</script>
</body>
</html>

CSS代码如下:

 

body {
    background
: url(img/bg_night_sunny.jpg) no-repeat;
    margin
: 0;
    padding
: 0;
}
.weather-container
{
    width
:640px;
    height
:360px;
    position
:relative;
}
.oneDayWeather
{
    position
: relative;
    overflow
: hidden;
    width
:105px;
    height
:360px;
    float
:left;
    text-align
: center;
    line-height
: 20px;
    color
:#fff;
    border-right
:1px solid rgba(255,255,255,0.25);
}
.oneDayWeather:last-child
{
    border
:none;
}
.oneDayWeather:active
{
    background
:rgba(0,0,0,0.2);
}
.pastDay
{
    opacity
: 0.6;
}
.weekDay
{
    position
: absolute;
    left
:0;
    top
:0;
    width
:100%;
}
.curWeather
{
    position
: absolute;
    left
:0;
    top
:20px;
    width
:100%;
}
.curWeatherPic
{
    position
: absolute;
    left
:0;
    top
:40px;
    width
:100%;
    height
:30px;
    background
:url(img/w1.png) center 0 no-repeat;
    background-size
:contain;
}
.highTemp,.lowTemp
{
    position
: absolute;
    left
:0;
    top
:-240px;
    width
:100%;
    height
:10px;
    background
: url(img/splash_indicator_focused.png) center 0 no-repeat;
}
.highTempNum,.lowTempNum
{
    position
: absolute;
    left
:0;
    top
:-20em;
    width
:100%;
    height
:20px;
    text-indent
: 15px
}
.dayWeatherPic
{
    position
: absolute;
    left
:0;
    bottom
:40px;
    width
:100%;
    height
:30px;
    background
:url(img/w2.png) center 0 no-repeat;
    background-size
:contain;
}
.dayWeather
{
    position
: absolute;
    left
:0;
    bottom
:20px;
    width
:100%;
}
.dayDate
{
    position
: absolute;
    left
:0;
    bottom
:0;
    width
:100%;
}
#myCanvas
{
    position
:absolute;
    top
:105px;
    left
:0;
}

 

posted @ 2015-06-11 20:32  逸乐太子  阅读(2087)  评论(1编辑  收藏  举报