Pulling Google Sheets as data source for Google Gantt Chart

Question

I'm attempting to pull data from Google Sheets and use it as a source for my Gantt chart . I've followed the example in the Google Charts documentation for pulling Sheets data for a columnchart , but not sure if more customization is necessary.

I'm not as familiar with Javascript, so not sure what is triggering the error. Here is the code in JSFiddle .

google.charts.load('current', {'packages':['gantt']});
google.charts.setOnLoadCallback(drawChart);

function daystoMilliseconds(days) {
  return days * 24 * 60 * 60 * 1000;
}

function drawGID() {
  var queryString = encodeURIComponent('SELECT A, B, C, D, E, F, G, H');

  var query = new google.visualization.Query(
      'https://docs.google.com/spreadsheets/d/1f0wxDrEfptRKCRY5pQPu6Dc_ue_tIX_ja5pQO3vXjOY/edit#gid=0&headers=1&tq=' + queryString);
  query.send(handleSampleDataQueryResponse);
}

function handleSampleDataQueryResponse(response) {
  if (response.isError()) {
    alert('Error in query: ' + response.getMessage() + ' ' + response.getDetailedMessage());
    return;
  }}

function drawChart() {

  var otherData = response.getDataTable();

  var options = {
    height: 275,
    gantt: {
      defaultStartDateMillis: new Date(2015, 3, 28)
    }
  };

  var chart = new google.visualization.Gantt(document.getElementById('chart_div'));

  chart.draw(otherData, options);
}

Answer 1

first, the callback should be --> drawGID

instead of --> drawChart

---

next, notice the data format for a Gantt chart

both the 'Start' and 'End' dates are required and cannot be blank,
as in the spreadsheet

---

see following working snippet...

a new data table is built, using the data from the spreadsheet ( otherData ),
using the 'Duration' column to fill in the the dates

 google.charts.load('current', { callback: drawGID, packages: ['gantt'] }); function drawGID() { var queryString = encodeURIComponent('SELECT A, B, C, D, E, F, G, H'); var query = new google.visualization.Query( 'https://docs.google.com/spreadsheets/d/1f0wxDrEfptRKCRY5pQPu6Dc_ue_tIX_ja5pQO3vXjOY/edit#gid=0&headers=1&tq=' + queryString); query.send(handleSampleDataQueryResponse); } function handleSampleDataQueryResponse(response) { if (response.isError()) { alert('Error in query: ' + response.getMessage() + ' ' + response.getDetailedMessage()); return; } var otherData = response.getDataTable(); var ganttData = new google.visualization.DataTable({cols: [ {type: 'string', label: 'Task Id'}, {type: 'string', label: 'Task Name'}, {type: 'string', label: 'Resource'}, {type: 'date', label: 'Start'}, {type: 'date', label: 'End'}, {type: 'number', label: 'Duration'}, {type: 'number', label: '% Complete'}, {type: 'string', label: 'Dependencies'} ]}); var duration = 0; var startDate = new Date(2016, 0, 1); var endDate; for (var i = 0; i < otherData.getNumberOfRows(); i++) { startDate = new Date(startDate.getTime() + duration); duration += otherData.getValue(i, 5); endDate = new Date(startDate.getTime() + duration); ganttData.addRow([ otherData.getValue(i, 0), otherData.getValue(i, 1), otherData.getValue(i, 2), startDate, endDate, otherData.getValue(i, 5), parseFloat(otherData.getValue(i, 6)), otherData.getValue(i, 7) ]); } var options = { height: 275, gantt: { defaultStartDateMillis: new Date(2015, 3, 28) } }; var chart = new google.visualization.Gantt(document.getElementById('chart_div')); chart.draw(ganttData, options); }

 <script src="https://www.gstatic.com/charts/loader.js"></script> <div id="chart_div"></div>

Answer 2

The following Google project allows you to view a Google Spreadsheet as a Gantt Chart: https://github.com/google/ezgantt