Javascript Canvas使用chart.js剪切饼图的边缘
与上图一样,Javascript Canvas使用chart.js剪切饼图的边缘,javascript,html,canvas,Javascript,Html,Canvas,与上图一样,canvas切掉饼图的边缘。我正在尝试调整画布的宽度和高度。当宽度较高时,底部将被切割,当高度较高时,侧面将被切割 下面是我在php for canvas中的代码: printf('<table>'); echo '<tr><td style="text-align: right;"><canvas id="pie-canvas-' . $canvasId
canvas
切掉饼图的边缘。我正在尝试调整画布的宽度和高度。当宽度较高时,底部将被切割,当高度较高时,侧面将被切割
下面是我在php for canvas中的代码:
printf('<table>');
echo '<tr><td style="text-align: right;"><canvas id="pie-canvas-'
. $canvasId
. '" width=256 height=256 style="width=300px;height=300px"></canvas></td><td style="text-align: left;width:360px;" id="legend" class="chart-legend"></td></tr>';
echo '<script type="text/javascript">drawPie('
. $canvasId
. ', '
. $data
.', '
. $legend
. ');</script>';
printf(“”);
回声';
回音“drawPie('
$canvasId
. ', '
.$数据
.', '
.$legend
. ');';
Javascript:
printf( '<script type="text/javascript" src="django/static/js/Chart.min.js"></script>' );
printf( '<script type="text/javascript" src="extlib/jquery-min.js"></script>' );
printf( '<script type="text/javascript">' );
?>
function drawPie( canvasId, data, legend )
{
var canvas = document.getElementById("pie-canvas-" + canvasId);
var ctx = canvas.getContext("2d");
var midX = canvas.width/2;
var midY = canvas.height/2;
var piedata = [];
$.each(data,function(i,val){
piedata.push({value:val.count,color:val.color,label:val.status});
});
var myPieChart = new Chart(ctx).Pie(piedata, {
showTooltips: false,
onAnimationProgress: drawSegmentValues
});
var radius = myPieChart.outerRadius;
function drawSegmentValues()
{
var length = myPieChart.segments.length;
var totalValue = 0;
for (var i=0; i< length; i++)
{
totalValue +=myPieChart.segments[i].value;
}
for(var i=0; i< length; i++)
{
ctx.fillStyle="black";
var textSize = canvas.width/15;
ctx.font= textSize+"px Verdana";
// Get needed variables
var value = Math.round(((myPieChart.segments[i].value)/totalValue)*100);
var startAngle = myPieChart.segments[i].startAngle;
var endAngle = myPieChart.segments[i].endAngle;
var middleAngle = startAngle + ((endAngle - startAngle)/2);
// Compute text location
var posX = (radius/1.5) * Math.cos(middleAngle) + midX;
var posY = (radius/1.5) * Math.sin(middleAngle) + midY;
// Text offside by middle
var w_offset = ctx.measureText(value).width/2;
var h_offset = textSize/4;
ctx.fillText(value+"%", posX - w_offset, posY + h_offset);
}
}
if(legend)document.getElementById("legend").innerHTML = myPieChart.generateLegend();
}
<?php
printf('</script>');
printf(“”);
printf(“”);
printf(“”);
?>
函数drawPie(画布ID、数据、图例)
{
var canvas=document.getElementById(“饼图画布-”+canvasId);
var ctx=canvas.getContext(“2d”);
var midX=canvas.width/2;
var midY=canvas.height/2;
var piedata=[];
$。每个(数据、函数(i、val){
push({value:val.count,color:val.color,label:val.status});
});
var myPieChart=新图表(ctx).Pie(piedata{
showTooltips:false,
onAnimationProgress:DrawSegmentValue
});
var半径=myPieChart.outerRadius;
函数值()
{
变量长度=myPieChart.segments.length;
var totalValue=0;
对于(变量i=0;i 你需要掷骰子的高度和宽度应该等于你的中间[X/Y]半径。这里可能存在舍入问题,因此如果您希望像素完美,可以使用像素数据。我已经给出了像素的宽度和高度。但仍然存在相同的问题。请详细说明您的答案。您可以从画布的中上像素(canvas.width/2,0)开始,循环Y+1,直到您看到当前像素不是灰色而是白色(外圆)你能举个例子吗?