New data is being placed on top of old data (JavaScript)

I’m a newbie to the web development world, so please pardon me if I miss something here and there or if I describe the issue incorrectly.

GIF illustrating the issue

Basically, I copied different code from TradingView’s two or more chart examples into one JSFiddle and tried to make a chart that could show candlesticks of different time frames with the symbol name, OHLCV, MA10 values. Everything works fine when the chart loads for the first time but when click the button to change the time frame, all the candles and MA10 line loads fine but the OHLCV and MA10 values seem like being put on the old (initially loaded) data. When I tried it for the first time all the candles and MA10 lines were also overlapping then I figured that the whole chart has to be removed so that MA10’s values will be re-calculated. So now the candlesticks and MA10 are loading fine but OHLCV values are still overlapping on the previous values. Since I’m new to JS I can’t figure out the right keywords for my problem so I’m not getting results that address my problem. Could somebody help me to figure out what’s going wrong?

Thank you.

I had to remove most of historic data to comply with Stackoverflow’s limit of 30000 chars per post, so snippet below will not work propely. You can take a look at the code here https://jsfiddle.net/akshay7892/dhutrgfn/7/

function createSimpleSwitcher(items, activeItem, activeItemChangedCallback) {
    var switcherElement = document.createElement('div');
    switcherElement.classList.add('switcher');

    var intervalElements = items.map(function(item) {
        var itemEl = document.createElement('button');
        itemEl.innerText = item;
        itemEl.classList.add('switcher-item');
        itemEl.classList.toggle('switcher-active-item', item === activeItem);
        itemEl.addEventListener('click', function() {
            onItemClicked(item);
        });
        switcherElement.appendChild(itemEl);
        return itemEl;
    });

    function onItemClicked(item) {
        if (item === activeItem) {
            return;
        }

        intervalElements.forEach(function(element, index) {
            element.classList.toggle('switcher-active-item', items[index] === item);
        });

        activeItem = item;

        activeItemChangedCallback(item);
    }

    return switcherElement;
}




function calculateSMA(data, count){
  var avg = function(data) {
    var sum = 0;
    for (var i = 0; i < data.length; i++) {
       sum += data[i].close;
    }
    return sum / data.length;
  };
  var result = [];
  for (var i=count - 1, len=data.length; i < len; i++){
    var val = avg(data.slice(i - count + 1, i));
    result.push({ time: data[i].time, value: val});
  }
  //console.log(result)
  return result;
}

function calopen(data){
  var open = [];
    for (var i = 0; i < data.length; i++) {
    open.push({ time: data[i].time, value: data[i].open});
  }
  
  return open;
}
//console.log(calopen(data))

function calhigh(data){
  var high = [];
    for (var i = 0; i < data.length; i++) {
    high.push({ time: data[i].time, value: data[i].high});
  }
  
  return high;
}

function callow(data){
  var low = [];
    for (var i = 0; i < data.length; i++) {
    low.push({ time: data[i].time, value: data[i].low});
  }
  
  return low;
}

function calclose(data){
  var close = [];
    for (var i = 0; i < data.length; i++) {
    close.push({ time: data[i].time, value: data[i].close});
  }
  
  return close;
}

function calv(data){
  var vol = [];
    for (var i = 0; i < data.length; i++) {
    vol.push({ time: data[i].time, value: data[i].volume});
  }
  
  return vol;
}

var one_minData = [{"time":1650350460,"open":329.35,"high":329.45,"low":329.1,"close":329.45,"volume":9795},{"time":1650350520,"open":329.45,"high":329.5,"low":329.15,"close":329.15,"volume":20626},{"time":1650350580,"open":329.15,"high":329.45,"low":329.15,"close":329.45,"volume":8762},{"time":1650350640,"open":329.5,"high":330.2,"low":329.25,"close":330.05,"volume":56546},{"time":1650350700,"open":330.15,"high":330.15,"low":329.55,"close":329.8,"volume":23489},{"time":1650350760,"open":329.8,"high":329.9,"low":329.6,"close":329.75,"volume":20630},]

var fifteen_minData = [{"time":1576728900,"open":509.8,"high":512.6,"low":508.9,"close":511.05,"volume":210630},{"time":1576729800,"open":511.0,"high":511.5,"low":509.35,"close":510.25,"volume":109974},{"time":1576730700,"open":510.25,"high":510.25,"low":506.2,"close":507.65,"volume":177816},]

var dayData = [{"time":1564963200,"open":460.0,"high":475.9,"low":455.85,"close":471.95,"volume":1465110},{"time":1565049600,"open":472.0,"high":487.5,"low":468.25,"close":482.15,"volume":795823},{"time":1565136000,"open":484.0,"high":489.95,"low":474.0,"close":477.25,"volume":312625},]

var weekData = 
    [{"time":1529884800,"open":538.35,"high":542.0,"low":508.0,"close":526.55,"volume":590970},{"time":1530489600,"open":530.0,"high":567.8,"low":523.0,"close":544.3,"volume":550127},{"time":1531094400,"open":548.8,"high":588.8,"low":544.5,"close":568.95,"volume":1021330},{"time":1531699200,"open":558.25,"high":706.8,"low":544.55,"close":687.4,"volume":3131754}{"time":1566777600,"open":484.0,"high":497.65,"low":455.15,"close":469.6,"volume":775278},];

var intervals = ['1','15','1D', '1W'];

var seriesesData = new Map([
  ['1', one_minData ],
  ['15', fifteen_minData ],
  ['1D', dayData ],
  ['1W', weekData ],
]);

var switcherElement = createSimpleSwitcher(intervals, intervals[0], syncToInterval);


document.body.style.position = 'relative';

var container = document.createElement('div');
document.body.appendChild(container);
document.body.appendChild(switcherElement);

var width = 600;
var height = 300;



var candleSeries = null;


function syncToInterval(interval) {
    if (candleSeries) {
        chart.remove();
    chart.remove(legend);
    
        //req_data = null;
    
   
    
    }
  chart = LightweightCharts.createChart(container, {
    width: width,
    height: height,
  crosshair: {
        mode: LightweightCharts.CrosshairMode.Normal,
    },
  timeScale: {
        borderVisible: true,
    timeVisible: true,
    secondsVisible: false,},
});
    candleSeries = chart.addCandlestickSeries();
  req_data = seriesesData.get(interval)
  //console.log(data);
  candleSeries.setData(req_data);
  
  
  ////charts time, volume, color data////////
  
    
    
  var smaLine = chart.addLineSeries({
    color: 'rgba(4, 111, 232, 1)',
  
    lineWidth: 2,
        });
    
    var openLine = chart.addLineSeries({
    color: 'rgba(4, 111, 232, 1)',
  visible: false,
    lineWidth:0,
    });

    var highLine = chart.addLineSeries({
    color: 'rgba(4, 111, 232, 1)',
  visible: false,
    lineWidth:0,
    });
    
  var lowLine = chart.addLineSeries({
    color: 'rgba(4, 111, 232, 1)',
  visible: false,
    lineWidth:0,
    });
  
    var closeLine = chart.addLineSeries({
    color: 'rgba(4, 111, 232, 1)',
  visible: false,
    lineWidth:0,
    });
  
  var volumeSeries = chart.addHistogramSeries({
    color: '#26a69a',
    priceFormat: {
        type: 'volume',
    },
    priceScaleId: '',
    scaleMargins: {
        top: 0.8,
        bottom: 0,
    },
    });
    
  var volLine = chart.addLineSeries({
    color: 'rgba(4, 111, 232, 1)',
  visible: false,
    lineWidth:5,
    });

    function setLegend6Text(fysymbol) {
   legend6.innerHTML = '<span style=style="font-size: 24px; margin: 4px 0px; color: #20262E">' + fysymbol + '</span>';
  //console.log("name",fysymbol);
}


function setLegendText(priceValue) {
    let val = 'n/a';
    if (priceValue !== undefined) {
        val = (Math.round(priceValue * 100) / 100).toFixed(2);
    }
  
    legend.innerHTML = '<br/><br/>MA10: <span style="color:rgba(4, 111, 232, 1); margin: 4px 0px;">' + val + '</span>';
}


function setLegendText1(openValue) {
    let openVal = 'n/a';
  if (openValue !== undefined) {
        openVal = (Math.round(openValue * 100) / 100).toFixed(2);
    }
  
    legend1.innerHTML = '<br/>O: <span style="color:rgba(4, 111, 232, 1); margin: 4px 0px;">' + openVal + '</span>';
}

function setLegendText2(highValue) {
    let highVal = 'n/a';
  if (highValue !== undefined) {
        highVal = (Math.round(highValue * 100) / 100).toFixed(2);
    }
  
    legend2.innerHTML = '<br/>H: <span style="color:rgba(4, 111, 232, 1); margin: 4px 0px;">' + highVal + '</span>';
}

function setLegendText3(lowValue) {
    let lowVal = 'n/a';
  if (lowValue !== undefined) {
        lowVal = (Math.round(lowValue * 100) / 100).toFixed(2);
    }
  
    legend3.innerHTML = '<br/>L: <span style="color:rgba(4, 111, 232, 1); margin: 4px 0px;">' + lowVal + '</span>';
}


function setLegendText4(closeValue) {
    let closeVal = 'n/a';
  if (closeValue !== undefined) {
        closeVal = (Math.round(closeValue * 100) / 100).toFixed(2);
    }
  
    legend4.innerHTML = '<br/>C: <span style="color:rgba(4, 111, 232, 1); margin: 4px 0px;">' + closeVal + '</span>';
}


function setLegendText5(volValue) {
    let volVal = 'n/a';
  if (volValue !== undefined) {
        volVal = (Math.round(volValue * 100) / 100).toFixed(2);
    }
  
    legend5.innerHTML = '<br/>V: <span style="color:rgba(4, 111, 232, 1); margin: 4px 0px;">' + (volVal/100000) + 'L' + '</span>';
}
  
  
  

    
  //console.log(lowdata)

    var legend = document.createElement('div');
    legend.className = 'sma-legend';
    container.appendChild(legend);
    legend.style.display = 'block';
    legend.style.left = 3 + 'px';
    legend.style.top = 20 + 'px';

     var legend1 = document.createElement('div');
   legend1.className = 'OHLC-legend';
   container.appendChild(legend1);
   legend1.style.display = 'block';
   legend1.style.left = 3 + 'px';
   legend1.style.top = 10 + 'px';


   var legend2 = document.createElement('div');
   legend2.className = 'OHLC-legend';
   container.appendChild(legend2);
   legend2.style.display = 'block';
   legend2.style.left = 78 + 'px';
   legend2.style.top = 10 + 'px';


   var legend3 = document.createElement('div');
   legend3.className = 'OHLC-legend';
   container.appendChild(legend3);
   legend3.style.display = 'block';
   legend3.style.left = 153 + 'px';
   legend3.style.top = 10 + 'px';


   var legend4 = document.createElement('div');
   legend4.className = 'OHLC-legend';
   container.appendChild(legend4);
   legend4.style.display = 'block';
   legend4.style.left = 228 + 'px';
   legend4.style.top = 10 + 'px';



   var legend5 = document.createElement('div');
   legend5.className = 'V-legend';
   container.appendChild(legend5);
   legend5.style.display = 'block';
   legend5.style.left = 303 + 'px';
   legend5.style.top = 10 + 'px';


   var legend6 = document.createElement('div');
   legend6.className = 'fysymbol-legend';
   container.appendChild(legend6);
   legend6.style.display = 'block';
   legend6.style.left = 3 + 'px';
   legend6.style.top = 0 + 'px';


   var fysymbol = "NSE:SBIN-EQ";
   
   

    voldata = calv(req_data)
  volumeSeries.setData(voldata)
    volLine.setData(voldata);

    smaData = calculateSMA(req_data, 10);
    smaLine.setData(smaData);

    
    opendata = calopen(req_data)
    openLine.setData(opendata);

    
    highdata = calhigh(req_data)
    highLine.setData(highdata);

    lowdata = callow(req_data)
  lowLine.setData(lowdata);

    closedata = calclose(req_data)
    closeLine.setData(closedata);
  
      
   
   var datesForMarkers = [req_data[req_data.length - 39], req_data[req_data.length - 19]];
var indexOfMinPrice = 0;
for (var i = 1; i < datesForMarkers.length; i++) {
    if (datesForMarkers[i].high < datesForMarkers[indexOfMinPrice].high) {
        indexOfMinPrice = i;
    }
}

var markers = [{ time: req_data[req_data.length - 48].time, position: 'aboveBar', color: '#f68410', shape: 'circle', text: 'D' }];
for (var i = 0; i < datesForMarkers.length; i++) {
    if (i !== indexOfMinPrice) {
        markers.push({ time: datesForMarkers[i].time, position: 'aboveBar', color: '#e91e63', shape: 'arrowDown', text: 'Sell @ ' + Math.floor(datesForMarkers[i].high - 1) });
    } else {
        markers.push({ time: datesForMarkers[i].time, position: 'belowBar', color: '#2196F3', shape: 'arrowUp', text: 'Buy @ ' + Math.floor(datesForMarkers[i].low + 1) });
    }
}

candleSeries.setMarkers(markers);
    setLegendText(smaData[smaData.length - 1].value);
   setLegendText1(opendata[opendata.length -1 ].value);
   setLegendText2(highdata[highdata.length -1 ].value);
   setLegendText3(lowdata[lowdata.length -1 ].value);
   setLegendText4(closedata[closedata.length -1 ].value);
   setLegendText5(voldata[voldata.length -1 ].value);
   setLegend6Text(fysymbol);
    chart.subscribeCrosshairMove((param) => {
   setLegendText(param.seriesPrices.get(smaLine)),
   setLegendText1(param.seriesPrices.get(openLine)),
   setLegendText2(param.seriesPrices.get(highLine)),
   setLegendText3(param.seriesPrices.get(lowLine)),
   setLegendText4(param.seriesPrices.get(closeLine)),
   setLegendText5(param.seriesPrices.get(volLine)),
   setLegend6Text(fysymbol);
   });

     

   


}

syncToInterval(intervals[0]);
    
  
   

html,
body {
    font-family: 'Trebuchet MS', Roboto, Ubuntu, sans-serif;
    background: #f9fafb;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.switcher {
    display: flex;
    align-items: center;
    height: 30px;
    margin-top:8px;
    color: #2196F3;
}

.switcher-item {
    cursor: pointer;
    text-decoration: none;
    display: inline-block;
    padding: 6px 8px;
    font-size: 14px;
    color: #262b3e;
    background-color: transparent;
    margin-right: 8px;
    border: none;
    border-radius: 4px;
    outline: none;
}

.switcher-item:hover {
    background-color: #f2f3f5;
}

.switcher-active-item {
    text-decoration: none;
    cursor: default;
    color: #262b3e;
}

.switcher-active-item,
.switcher-active-item:hover {
    background-color: #e1eff9;
}


.sma-legend {
    width: 96px;
    height: 10px;
    position: absolute;
    padding: 8px;
    font-size: 14px;
    background-color: rgba(255, 255, 255, 0.23);
    text-align: left;
    z-index: 1000;
    pointer-events: none;
  white-space: normal;
}

.OHLC-legend {
    width: 96px;
    height: 10px;
    position: absolute;
    padding: 8px;
    font-size: 16px;
    background-color: rgba(255, 255, 255, 0.23);
    text-align: left;
    z-index: 1000;
    pointer-events: none;
  white-space: normal;
}

.V-legend {
    width: 120px;
    height: 70px;
    position: absolute;
    padding: 8px;
    font-size: 16px;
    background-color: rgba(255, 255, 255, 0.23);
    text-align: left;
    z-index: 1000;
    pointer-events: none;
  white-space: normal;
}


.fysymbol-legend {
    width: 250px;
    height: 70px;
    position: absolute;
    padding: 8px;
    /*font-size: 20px;*/
    background-color: rgba(255, 255, 255, 0.23);
    text-align: left;
    z-index: 1000;
    pointer-events: none;
  white-space: normal
}

<script src="https://unpkg.com/lightweight-charts@3.4.0/dist/lightweight-charts.standalone.production.js"></script>

Answer

First thing to look at when something’s not working as expected (whatever your level!) is the dev console! Here you can clearly see that each time you click on your button you’re not only replacing an “old” value but instead adding one on top of the previous one(s).

I would recommend having an init function and/or components and an update function.