可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试):

问题:

Anyone know how to create a circle "progressbar" in svg? I need to specify the percentage of the circle, så that a color grows in the shape of a cake.

The growing can be static as long as I have a attribute to change its current status.

回答1:

Following is the idea I used to use. With a bit of modification in css and animation tag we can achieve more effects for intuitive user experiences.

---SAMPLE CODE----

svg{
    
    			}
    			.over{
    	  			-webkit-animation: rotator 1.5s ease-in-out infinite;
    	  			stroke-dasharray: 107,38;
    			}
    			.bag{
    				position: absolute;
    			}
    			@-webkit-keyframes rotator {
                  	0% { transform: rotate(0deg); }
                  	100% { transform: rotate(360deg); }
                }
                .container{
    
                }

<div class="container">
  <svg class="bag" height="100" width="100">
    <circle  cx="50" cy="50" r="40" stroke="#F8BBD0" stroke-width="3" fill="none">
    </circle>
  </svg>
  <svg class="over" height="100" width="100">
    <circle  cx="50" cy="50" r="40" stroke="#E91E63" stroke-width="3" fill="none" >
      <animate attributeType="CSS" attributeName="stroke-dasharray" from="1,254" to="247,56" dur="5s" repeatCount="indefinite" />
    </circle>
  </svg>
</div>

Hope you were looking for something kind of this. :)

回答2:

Thanks, boldewyn.

To answer my own question, I found the following solution:

One can use the following path in template:

<path id="progress" fill="none" stroke="#ffffff" d="" stroke-width="10"/>

And use this function from Raphael js-framework to update x and y. If total is 100, value is the percentage of progress:

function updateState (value, total, R) {
    var center;
    var alpha = 360 / total * value,
        a = (90 - alpha) * Math.PI / 180,
        x = 300 + R * Math.cos(a),
        y = 300 - R * Math.sin(a),
        path;
    if (total == value) {
        path = "M"+ 300 +","+ (300 - R) +" A"+ R+","+ R+","+ 0+","+ 1+","+ 1+","+ 299.99+","+ 300 - R;
    } else {
        if(alpha > 180) {
            center = 1;
        } else {
            center = 0;
        }
        path = "M"+ 300+","+ (300 - R) +" A"+ R+","+ R+","+ 0+"," + center +","+ 1+","+ x+","+ y;
    }
    return path;
}

The returned path variable is the value for the d attribute on the path element.

This works perfect, if your browser supports SVG Full with the Elliptical Arc command for the path-element. In my case I only have SVG tiny, so this wont work for me :(

回答3:

Use this self implemented method in JavaScript for example here percentage=85

HTML Code:

<p style="position:absolute;margin-left:95px;margin-top:50px;" id="percentage">0 %</p>  
<svg style="position:absolute" id="svg_test" version="1.1" xmlns="http://www.w3.org/2000/svg">
<circle style="-webkit-tap-highlight-color: rgba(0, 0, 0, 0);" cx="110" cy="60" r="50" fill="none" stroke="#e4e4e4" stroke-width="2"></circle>
<path id="svgpath" style="-webkit-tap-highlight-color: rgba(0, 0, 0, 0);" fill="none" stroke="#16a6b6" d="M60,60 A50,50 0 0,1 160,60" stroke-width="2"></path>
</svg>

<circle style="-webkit-tap-highlight-color: rgba(0, 0, 0, 0);" cx="110" cy="60" r="50" fill="none" stroke="#e4e4e4" stroke-width="2"></circle>
<path id="svgpath" style="-webkit-tap-highlight-color: rgba(0, 0, 0, 0);" fill="none" stroke="#16a6b6" d="M60,60 A50,50 0 0,1 160,60" stroke-width="2"></path>
</svg>

jQuery Code:

    percentage=85
    if(percentage>=50)
    {
        flag=1;
    }
    var per=0;
    $(svg).animate({ 'to': 1 }, {
    duration: 2000,
    step: function(pos, fx) {

        //var offset = (pos);
        if(pos<0.5)
        {
            if(percentage>=50)
            {
                per=180;
                $('#percentage').html(Math.round(pos*100)+" %");
            }
            else
            {
                per=(percentage*180/50);
                $('#percentage').html(Math.round(percentage*pos*2)+" %");
            }

            endx=110-50*Math.cos(0+(Math.PI/180)*per*(pos*2));
            endy=60-50*Math.sin(0+(Math.PI/180)*per*(pos*2));
            svg.setAttribute('d',current_dx+endx+","+endy);
        }   
        else if(pos>=0.5 && pos!=1 && flag==1)
        {
            per=((percentage-50)*180/50);
            $('#percentage').html(Math.round(50+(percentage-50)*(pos-0.5)*2)+" %");
            endx=110+50*Math.cos(0+(Math.PI/180)*per*(pos-0.5)*2);
            endy=60+50*Math.sin(0+(Math.PI/180)*per*(pos-0.5)*2);
            svg.setAttribute('d',current_d+endx+","+endy);

        }


    }
});

Demo : Click Here

回答4:

Shamelessly copy and pasting from the specification:

<path d="M275,175 v-150 a150,150 0 0,0 -150,150 z"
    fill="yellow" stroke="blue" stroke-width="5" />

The path uses the "elliptical arc" command to draw a partial circle. You can either draw several of them, each describing a different circular section, or you give one of them an ID and reference it with <use xlink:href="#ID" />. Then you can rotate the <use/>. Draw as many of them as you need for granularity (e.g., 100 sectors allow you steps of 0% to 100%).

To colorize them, just set the fill="" attribute of each single sector to the fitting value.

回答5:

Some time ago, I was needing one so I studied a lot to get it done. All you need is a simple SVG markup with the right coordinates, a bit of CSS for it and a little bit of JS (to allow change the % of the progress bar). But at same time you can generate the SVG on the back-end with the right coordinates based on the % you want and unless your progress cannot be read-only, that would work as well.

This is the implementation: http://codepen.io/leandroico/pen/zwIHl

And this is the sample of the SVG markup:

<svg version="1.1" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100">
  <g class="arcs">
    <circle cx="50" cy="50" r="49" class="outer-circle" />
    <path d="M50 1 A 49 49, 0, 1, 1, 7.06 73.61, L 50 50 z" class="outer-arc" id="arc1" />
    <circle cx="50" cy="50" r="35" class="inner-circle"  />
    <path d="M50 15 A 35 35, 0, 1, 1, 19.33 66.86" class="inner-arc" id="arc2" />
  </g>
  <g class="circles">
    <circle cx="50" cy="50" r="49" class="outer-circle" />
    <circle cx="50" cy="50" r="35" class="inner-circle" />
  </g>
  <text x="50" y="58" id="percentage-label">67%</text>
</svg>

回答6:

<svg xmlns="http://www.w3.org/2000/svg" width="225" height="225">
    <g>
        <circle cx="112" cy="112" r="95"></circle>
        <path id="path" d="M 112,17 A 95,95 0 0,0 112,17"></path>
    </g>
</svg>
<script type="text/javascript">
    function polarToCartesian(centerX, centerY, radius, angleInDegrees) {
        var angleInRadians = angleInDegrees * Math.PI / 180.0;
        var x = centerX + radius * Math.cos(angleInRadians);
        var y = centerY + radius * Math.sin(angleInRadians);
        return [x, y];
    }
    function drawCircle(elm, centerX, centerY, radius, percentage) {
        var angle = (360 * (percentage / 100)) % 360;
        var start = polarToCartesian(centerX, centerY, radius, -90);
        var end = polarToCartesian(centerX, centerY, radius, -(angle + 90));
        var large = percentage < 50 ? 0 : 1;
        var length = (2 * Math.PI * radius) * (percentage / 100);
        console.log(start, end, angle);
        elm.setAttribute('d', 'M ' + start[0] + ',' + start[1] + ' A ' + radius + ',' + radius + ' ' + 0 + ' ' + large + ',' + 0 + ' ' + end[0] + ',' + end[1]);
        elm.setAttribute('stroke-dasharray', length);
        elm.setAttribute('stroke-dashoffset', length);
    }
    drawCircle(document.getElementById('path'), 112, 112, 95, 47);
</script>