制作餅狀圖
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>canvas繪制扇形圖</title>
<style>
body{
background:#ccc;
}
canvas{
background:#fff;
}
</style>
</head>
<body>
<canvas id="myCanvas"></canvas>
<script>
(function(){
//定義數據
var data = [
{title:"apple", value:0.24, color:"green"},
{title:"三星", value:0.26, color:"yellow"},
{title:"華為", value:0.13, color:"orange"},
{title:"錘子", value:0.17, color:"red"},
{title:"小米", value:0.08, color:"purple"},
{title:"其他", value:0.12, color:"cyan"}
];
var w=800;
var h=600;
var cx=w/2;
var cy=h/2;
var r=200;
//獲取canvas元素
var canvas=document.getElementById("myCanvas");
//設置畫布寬高
canvas.width=w;
canvas.height=h;
//獲取繪圖環境
var ctx=canvas.getContext("2d");
ctx.font="18px Micorsoft YaHei";
//遍歷數據
var beginAngle=Math.PI/6; //開始的點
data.forEach(function(item){
//弧度范圍
var angle=item.value*2*Math.PI;
//結束的點
var endAngle=beginAngle+angle;
//繪制扇形區域
ctx.beginPath();
ctx.moveTo(cx,cy);
ctx.arc(cx,cy,r,beginAngle,endAngle);
ctx.fillStyle=item.color;
ctx.fill();
//寫字
var txtAngle=beginAngle+angle/2;
if(txtAngle>=Math.PI/2 && txtAngle<Math.PI*3/2){
ctx.textAlign="end";
}else{
ctx.textAlign="start";
}
var tx=cx+(r+10)*Math.cos(txtAngle);//Math.cos(x) x 的余弦值。返回的是 -1.0 到 1.0 之間的數；
var ty=cy+(r+10)*Math.sin(txtAngle);//Math.sin(x) x 的正玄值。返回值在 -1.0 到 1.0 之間；
ctx.fillText(item.title+" "+item.value*100+"%",tx,ty);
beginAngle=endAngle;
})
})()
</script>
</body>
</html>
Konva制作動態餅狀圖
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>扇形圖</title>
<style>
body{
background:#ccc;
}
.konvajs-content{
background:#fff;
}
</style>
</head>
<body>
<div id="box"></div>
<script src="konva.js"></script>
<script>
var radius=150;
var duration=1;
var data = [
{title:"apple", value:0.24, color:"pink"},
{title:"三星", value:0.26, color:"skyblue"},
{title:"華為", value:0.13, color:"orange"},
{title:"錘子", value:0.17, color:"red"},
{title:"小米", value:0.08, color:"purple"},
{title:"其他", value:0.12, color:"cyan"}
];
//創建舞台
var stage=new Konva.Stage({
container:"#box",
width:800,
height:600
})
//創建層
var layer=new Konva.Layer({
});
stage.add(layer);
//創建扇形的組
var wedgeGroup=new Konva.Group({
x:stage.getWidth()/2,
y:stage.getHeight()/2
});
//創建文字的組
var textGroup=new Konva.Group({
x:stage.getWidth()/2,
y:stage.getHeight()/2
})
var startAngle=0;
data.forEach(function(item,index){
var angle=item.value*360;
//繪制扇形
var wedgeShape=new Konva.Wedge({
x:0,
y:0,
radius:radius,
angle:0,
rotation:startAngle,
fill:item.color,
name:angle+""
});
wedgeGroup.add(wedgeShape);
//繪制文字
var textAngle=startAngle+angle/2;//文字對應的角度
var textX=Math.cos(textAngle/180*Math.PI)*(radius+30);
var textY=Math.sin(textAngle/180*Math.PI)*(radius+30);
var text=new Konva.Text({
text:item.title,
x:textX,
y:textY,
fill:item.color,
fontSize:12,
visible:false
});
if(textAngle>90&&textAngle<270){
text.x(text.x()-text.getWidth())
}
textGroup.add(text);
startAngle+=angle;
});
//繪制外圓
var outerCircle=new Konva.Circle({
x:stage.getWidth()/2,
y:stage.getHeight()/2,
radius:radius+5,
stroke:"#ccc",
strokeWidth:1
});
layer.add(wedgeGroup);
layer.add(textGroup);
layer.add(outerCircle);
layer.draw();
//設置動畫來讓扇形動起來
var wedgeList=wedgeGroup.getChildren();
var animateIndex=0;
playAnimate();//調用函數執行動畫
function playAnimate(){
if(animateIndex>=data.length){
return;
}
var wedge=wedgeList[animateIndex];
var angle=Number(wedge.name());
var animateDuration=duration*(angle/360);
wedge.to({
angle:angle,
duration:animateDuration,
onFinish:function(){
textGroup.getChildren()[animateIndex].show();
animateIndex++;
playAnimate();
}
})
}
</script>
</body>
</html>
制作折線圖
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>折線圖</title>
<style>
body{
background:#ccc;
}
</style>
</head>
<body>
<canvas id="myCanvas"></canvas>
<script>
//定義相關數據 最大100
var data=[
{year:"2008",value:40},
{year:"2009", value:48},
{year:"2010", value:50},
{year:"2011", value:70},
{year:"2012", value:60},
{year:"2013", value:40},
{year:"2014", value:20},
{year:"2015", value:60},
{year:"2016", value:80},
{year:"2017", value:90}
];
var xWidth=40;//x軸每一個格子寬度
var yWidth=40;//y軸每一個格子寬度
var x=100,y=500;//原點坐標
var len=data.length;//數據長度
//獲取canvas元素
var canvas=document.querySelector("#myCanvas");
canvas.width=800;
canvas.height=600;
canvas.style.border="1px solid #ccc";
canvas.style.backgroundColor="#fff";
//獲取繪圖環境
var ctx=canvas.getContext("2d");
//繪制坐標系
ctx.beginPath();
//x軸
var xLength=xWidth*(len+1);//x軸長度
ctx.moveTo(x,y);
ctx.lineTo(x+xLength,y);//箭頭
ctx.lineTo(x+xLength-10,y-10);//上箭頭
ctx.moveTo(x+xLength,y);//下箭頭
ctx.lineTo(x+xLength-10,y+10);//下箭頭
//刻度
ctx.textAlign="center";
ctx.textBaseline="top";
for(var i=1;i<=len;i++){
ctx.moveTo(x+xWidth*i,y);
ctx.lineTo(x+xWidth*i,y-10);
ctx.fillText(data[i-1].year,x+xWidth*i,y);
}
//y軸
var yLength=yWidth*(len+1);
ctx.moveTo(x,y);
ctx.lineTo(x,y-yLength);
//箭頭
ctx.lineTo(x-10,y-yLength+10);//左箭頭
ctx.moveTo(x,y-yLength);//右箭頭
ctx.lineTo(x+10,y-yLength+10);//右箭頭
//刻度
ctx.textAlign="end";
ctx.textBaseline="middle";
for(var i=0;i<=10;i++){
ctx.moveTo(x,y-i*yWidth);
ctx.lineTo(x+10,y-i*yWidth);
ctx.fillText(i*10,x-5,y-i*yWidth)
}
ctx.strokeStyle="orange";
ctx.stroke();
//繪制折線圖
ctx.beginPath();
data.forEach(function(item,index){
ctx.lineTo(x+(index+1)*xWidth,y-item.value/10*yWidth);
});
ctx.strokeStyle="purple";
ctx.stroke();
</script>
</body>
</html>
制作柱形圖
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>柱形圖</title>
<style>
body{
background:#ccc;
}
</style>
</head>
<body>
<canvas id="myCanvas"></canvas>
<script>
//定義相關數據 最大100
var data=[
{city:"北京",number:345,color:"red"},
{city:"上海", number:645, color:"green"},
{city:"廣州", number:545, color:"#369"},
{city:"深圳", number:945, color:"purple"}
];
var x=100,y=500;//原點坐標
var xWidth=50;
var yWidth=40;
//獲取canvas元素
var canvas=document.querySelector("#myCanvas");
canvas.width=800;
canvas.height=600;
canvas.style.border="1px solid #ccc";
canvas.style.backgroundColor="#fff";
//獲取繪圖環境
var ctx=canvas.getContext("2d");
//繪制坐標 軸
ctx.save();
ctx.translate(x,y);
ctx.beginPath();
//x軸
ctx.moveTo(0,0);
ctx.lineTo(xWidth*9,0);
ctx.lineTo(xWidth*9-10,-10);
ctx.moveTo(xWidth*9,0);
ctx.lineTo(xWidth*9-10,10);
//y軸
ctx.moveTo(0,0);
ctx.lineTo(0,-yWidth*11);
ctx.lineTo(-10,-yWidth*11+10);
ctx.moveTo(0,-yWidth*11);
ctx.lineTo(10,-yWidth*11+10);
//刻度
ctx.textAlign="end";
ctx.textBaseline="middle";
for(var i=0;i<=10;i++){
ctx.moveTo(0,-i*yWidth);
ctx.lineTo(10,-i*yWidth);
ctx.fillText(i*100,-10,-i*yWidth);
}
ctx.strokeStyle="orange";
ctx.stroke();
//繪制餅狀圖
ctx.beginPath();
ctx.textAlign="center";
ctx.textBaseline="top";
data.forEach(function(item,index){
ctx.fillStyle=item.color;
ctx.fillRect(index*2*xWidth+xWidth,-item.number/100*yWidth,xWidth,item.number/100*yWidth);
ctx.fillText(item.city,index*2*xWidth+xWidth+xWidth/2,10);
})
ctx.restore();
</script>
</body>
</html>
