Dropdown Events in JavaScript

Use Plotly to create custom dropdowns in D3.js-based JavaScript charts.


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function makeTrace(i) {
    return {
        y: Array.apply(null, Array(10)).map(() => Math.random()),
        line: {
            shape: 'spline' ,
            color: 'red'
        },
        visible: i === 0,
        name: 'Data set ' + i,
    };
}

Plotly.newPlot('myDiv', [0, 1, 2, 3].map(makeTrace), {
    updatemenus: [{
        y: 0.8,
        yanchor: 'top',
        buttons: [{
            method: 'restyle',
            args: ['line.color', 'red'],
            label: 'red'
        }, {
            method: 'restyle',
            args: ['line.color', 'blue'],
            label: 'blue'
        }, {
            method: 'restyle',
            args: ['line.color', 'green'],
            label: 'green'
        }]
    }, {
        y: 1,
        yanchor: 'top',
        buttons: [{
            method: 'restyle',
            args: ['visible', [true, false, false, false]],
            label: 'Data set 0'
        }, {
            method: 'restyle',
            args: ['visible', [false, true, false, false]],
            label: 'Data set 1'
        }, {
            method: 'restyle',
            args: ['visible', [false, false, true, false]],
            label: 'Data set 2'
        }, {
            method: 'restyle',
            args: ['visible', [false, false, false, true]],
            label: 'Data set 3'
        }]
    }],
});
d3.csv('https://raw.githubusercontent.com/plotly/datasets/master/gapminderDataFiveYear.csv', function(err, rows){

    function unpack(rows, key) {
        return rows.map(function(row) { return row[key]; });
    }

    var allCountryNames = unpack(rows, 'country'),
        allYear = unpack(rows, 'year'),
        allGdp = unpack(rows, 'gdpPercap'),
        listofCountries = [],
        currentCountry,
        currentGdp = [],
        currentYear = [];

    for (var i = 0; i < allCountryNames.length; i++ ){
        if (listofCountries.indexOf(allCountryNames[i]) === -1 ){
            listofCountries.push(allCountryNames[i]);
        }
    }

    function getCountryData(chosenCountry) {
        currentGdp = [];
        currentYear = [];
        for (var i = 0 ; i < allCountryNames.length ; i++){
            if ( allCountryNames[i] === chosenCountry ) {
                currentGdp.push(allGdp[i]);
                currentYear.push(allYear[i]);
            }
        }
    };

    // Default Country Data
    setBubblePlot('Afghanistan');

    function setBubblePlot(chosenCountry) {
        getCountryData(chosenCountry);

        var trace1 = {
            x: currentYear,
            y: currentGdp,
            mode: 'lines+markers',
            marker: {
                size: 12,
                opacity: 0.5
            }
        };

        var data = [trace1];

        var layout = {
            title: {text: 'Line and Scatter Plot'},
            height: 400,
            width: 480
        };

        Plotly.newPlot('myDiv', data, layout);
    };

    var innerContainer = document.querySelector('[data-num="0"'),
        plotEl = innerContainer.querySelector('.plot'),
        countrySelector = innerContainer.querySelector('.countrydata');

    function assignOptions(textArray, selector) {
        for (var i = 0; i < textArray.length;  i++) {
            var currentOption = document.createElement('option');
            currentOption.text = textArray[i];
            selector.appendChild(currentOption);
        }
    }

    assignOptions(listofCountries, countrySelector);

    function updateCountry(){
        setBubblePlot(countrySelector.value);
    }

    countrySelector.addEventListener('change', updateCountry, false);
});