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.net Powerful JavaScript charts
About
RGraph is a JavaScript charts library based on HTML5 SVG and canvas. RGraph is mature (over 18 years old) and has a wealth of features making it an ideal choice to use for showing charts on your website.

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Version 7.20
Version 7.20 (released in June 2026) is the latest version of RGraph and the major change in this version is an update to the default values of properties making for better looking charts without having to set any properties. Read more about this and other changes in the changelog.

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Download
Get the latest version of RGraph (version 7.20, 9th June 2026) from the download page. You can read the changelog here. There's also older versions available, minified files and links to cdnjs.com hosted libraries.

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Latest forum posts
These are the latest support forum posts that have been posted or updated.


16th June, Rachel
I have a question about the 3D Bar chart
12th June, Marco
Should I use SVG or canvas for the charts on my website?
9th June, Richard
New version of RGraph: version 7.20
3rd June, Patrick
Question about installing RGraph
1st June, Ouja
How do I add a click event to a bar in my Bar chart?


Support forum »

 

License
RGraph can be used for free under the GPL or if that doesn't suit your situation there's an inexpensive (£129) commercial license available.

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Problems making the HorseShoe meter update


Posted by Kemal Serkan at 07:44 on Wednesday 27th January 2021 [link]
I can't refresh Pie charts according to coming data from my API, but i can refresh other HTML tags on the page. I am using this chart in Electron. Thank you

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Atolye-101</title>
    <link rel="stylesheet" href="../css/styles.css">
    <script src="../assets/jquery-3.5.1.min.js"></script>
    <link rel="stylesheet" href="../assets/bootstrap.min.css">
    <link rel="stylesheet" href="../css/styles.css">

    <script src="../assets/bootstrap.min.js"></script>

    <script src="../js/RGraph.common.core.js"></script>
    <script src="../js/RGraph.pie.js"></script>

</head>
<body onload="httpCall()">
<!--    <button class="btn btn-outline-primary" id="backBtn" style="margin: 10px">Geri</button>-->
    <button type="button" class="btn btn-outline-primary" id="backBtn" style="margin: 15px">
        <span class="glyphicon glyphicon-arrow-left"></span>
        Geri
    </button>

<div class="container">
    <div class="row justify-content-center">
        <h2>Atolye-101 Anl&#305;k &#304;zleme Ekran&#305;</h2>
    </div>

    <div class="row mt-4 justify-content-center">

        <div class="col-4">
            <h3 class="text-center">S&#305;cakl&#305;k</h3>
            <canvas id="temp" width="300" height="300" >[No canvas support]</canvas>
        </div>
        <div class="col-4">
            <h3 class="text-center">Nem</h3>
            <canvas id="hum" width="300" height="300" >[No canvas support]</canvas>
        </div>
        <div class="col-4">
            <h3 class="text-center">Hava Kalitesi</h3>
            <canvas id="iaq" width="300" height="300" >[No canvas support]</canvas>
        </div>
    </div>

    <div class="row mt-5 justify-content-center">
        <p id="NoS-101" class="h5">O&#287;renci Say&#305;s&#305; : 11</p>
    </div>
    <div class="row mt-3 justify-content-center">
        <p id="dateTime-101" class="h5">Son Kay&#305;t Zaman&#305; : 23/02/2021 11:34</p>
    </div>
</div>
<!--    <script src="../js/atolye101.js"></script>-->
<script>
    const ipcRenderer = require("electron").ipcRenderer
    const {session} = require('electron').remote;
    // window.$ = window.jquery = require("jquery");

    document.getElementById("backBtn").addEventListener("click",()=>{
        ipcRenderer.send("btnBack","101");
    })

    temp = new RGraph.HorseshoeMeter({
        id: 'temp',
        min: 0,
        max: 50,
        value: 15,
        options: {
            // Some options which you can give if you choose to:
            //
            colors: ["#3678c1", '#BED1E3'],
            //width: 25,
            //textSize: 65,
            textColor: "#3678c1",
            //textBold: true,
            //textItalic: true,
            //textFont: 'Georgia'
            //animationCallback: function () {$a('Finished!');}, // These can also be given as arguments to the animation function
            animationOptions: {frames: 60}                    // Doesn't need to be a string
        }
    }).draw();
    // }).roundRobin();
    // }).roundRobin(
    //     {frames: 60},
    //     function () {console.log('Animation complete!');}
    // );

    hum = new RGraph.HorseshoeMeter({
        id: 'hum',
        min: 0,
        max: 100,
        value: 45,
        options: {
            // Some options which you can give if you choose to:
            //
            colors: ["#3678c1", '#BED1E3'],
            //width: 25,
            //textSize: 65,
            textColor: "#3678c1",
            //textBold: true,
            //textItalic: true,
            //textFont: 'Georgia'
            //animationCallback: function () {$a('Finished!');}, // These can also be given as arguments to the animation function
            animationOptions: {frames: 60}                    // Doesn't need to be a string
        }
    }).draw();
    // }).roundRobin();
    // }).roundRobin(
    //     {frames: 60},
    //     function () {console.log('Animation complete!');}
    // );

    iaq = new RGraph.HorseshoeMeter({
        id: 'iaq',
        min: 0,
        max: 3000,
        value: 1232,
        options: {
            // Some options which you can give if you choose to:
            //
            colors: ["#3678c1", '#BED1E3'],
            //width: 25,
            //textSize: 65,
            textColor: "#3678c1",
            //textBold: true,
            //textItalic: true,
            //textFont: 'Georgia'
            //animationCallback: function () {$a('Finished!');}, // These can also be given as arguments to the animation function
            animationOptions: {frames: 60}                    // Doesn't need to be a string
        }
    }).draw();
    // }).roundRobin();
    // }).roundRobin(
    //     {frames: 60},
    //     function () {console.log('Animation complete!');}
    // );

    async function getSessionInfo(){
        let myPromise = new Promise(function(myResolve, myReject) {
            session.defaultSession.cookies.get({name: "human_presence"}, (error,cookies)=>{
                if(error){ myReject(error)}
                if(cookies.length>0){
                    let arr = cookies[0];
                    if(arr.name === "human_presence" && ( (Date.now()-arr.expirationDate) < 600000)){
                        let obj = JSON.parse(arr.value);
                        // console.log(obj.accessToken);
                        myResolve(obj.accessToken);
                    }
                    else{ myResolve("Token bulunamad&#305;")}
                }
            });
        });
        return await myPromise;
    }

    function httpCall(){
        getSessionInfo().then(function (val){
            console.log(val);
            let method = "GET";
            let url = "http://localhost:4000/classroom/101";
            let xmlHttpRequest = new XMLHttpRequest();
            xmlHttpRequest.addEventListener("readystatechange", function() {
                if(this.readyState === 4) {
                    console.log(this.responseText);

                    let obj = JSON.parse(this.responseText);
                    console.log(obj);
                    document.getElementById("dateTime-101").innerHTML = "Son Kay&#305;t Zaman&#305; : "+obj.created;
                    document.getElementById("NoS-101").innerHTML = "O&#287;renci Say&#305;s&#305; : "+obj.NoS;
                    temp.value = parseInt(obj.Temp);
                    hum.value = parseInt(obj.Hum);
                    iaq.value = parseInt(obj.IAQ);

                    console.log(temp.value);
                    console.log(hum.value);
                    console.log(iaq.value);

                    RGraph.redrawCanvas(temp.canvas);
                    RGraph.redrawCanvas(hum.canvas);
                    RGraph.redrawCanvas(iaq.canvas);
                }
            });
            xmlHttpRequest.open(method, url);
            xmlHttpRequest.setRequestHeader('Authorization', 'Bearer ' + val);
            xmlHttpRequest.send();
        })
    }

    window.onload = httpCall();
    window.setInterval(function(){
        httpCall();
    }, 20000);
</script>
</body>
</html>


Posted by Richard at 15:54 on Wednesday 27th January 2021 [link]
This is as a result of the HorseShoe meter not really being a 'real' RGraph chart object - but an adaptation of the Pie chart. As a result I think it's easier to just redraw the entire chart when you update it.

Here's some code:

<!DOCTYPE html >
<html>
<head>
    <script src="/libraries/RGraph.common.core.js" ></script>
    <script src="/libraries/RGraph.pie.js" ></script>
    
    <meta name="robots" content="noindex,nofollow" />
</head>
<body>

    <canvas id="cvs" width="400" height="400">[No canvas support]</canvas>

    <script>
        function draw (value)
        {
            RGraph.reset(document.getElementById('cvs'));

            new RGraph.HorseshoeMeter({
                id: 'cvs',
                min: 0,
                max: 10000,
                value: value,
                options: {
                }
            }).roundRobin();
        }
        
        delay = 2000;
        
        function update ()
        {
            var value = Math.random(0, 1000);

            draw(value * 10000);
            
            // Call ourselves again
            setTimeout(update, delay);
        }
        
        setTimeout(update, delay);
    </script>

</body>
</html>

And here's a CodePen of the code:

https://codepen.io/rgraph/pen/gOLYOej

Posted by Richard at 10:18 on Thursday 28th January 2021 [link]
For the next version I think I'm going to promote the Pie chart based meters (Horseshoe Meter, Segmented Meter, Activity Meter, RadialProgress Meter) to "real" chart objects instead of being based on the Pie chart. This will make it possible for animations to be better - in your case this would mean the chart wouldn't always animate from zero when it changes value. It looks much nicer when this is done.

Richard

[Replies are closed]