vertical reference line in google timeline visualization

Question

Hi I am using google visualization api to draw a timeline chart in my website. It works just fine. But there is one little thing that is bothering me. I want to display a vertical line in the chart area to represent the current date. Please let me know any kind of solutions.

My code:

<script type="text/javascript" src="https://www.google.com/jsapi?autoload={'modules':[{'name':'visualization','version':'1','packages':['timeline']}]}"></script>

<script type="text/javascript">
google.setOnLoadCallback(drawChart);
function drawChart() {

  var container = document.getElementById('example3.1');
  var chart = new google.visualization.Timeline(container);

  var dataTable = new google.visualization.DataTable();
  dataTable.addColumn({ type: 'string', id: 'Position' });
  dataTable.addColumn({ type: 'string', id: 'Name' });
  dataTable.addColumn({ type: 'date', id: 'Start' });
  dataTable.addColumn({ type: 'date', id: 'End' });
  dataTable.addRows([
    [ 'President',          'George Washington', new Date(2014, 3, 29), new Date(2014, 4, 3)],
    [ 'President',          'John Adams',        new Date(2014, 2, 3),  new Date(2014, 3, 3)],
    [ 'President',          'Thomas Jefferson',  new Date(2014, 2, 3),  new Date(2014, 5, 3)],
    [ 'Vice President',     'John Adams',        new Date(2014, 3, 20), new Date(2014, 5, 3)],
    [ 'Vice President',     'Thomas Jefferson',  new Date(2014, 2, 3),  new Date(2014, 6, 3)],
    [ 'Vice President',     'Aaron Burr',        new Date(2014, 2, 3),  new Date(2014, 2, 3)],
    [ 'Vice President',     'George Clinton',    new Date(2014, 2, 3),  new Date(2014, 2, 19)],

    ]);

  chart.draw(dataTable);
}

</script>

<div id="example3.1" style="width: 1000px; height: 200px;"></div>

Intended Result: Green Line represents current date

Edit:

If this is not possible, please suggest any other API which can achieve this.

Answer 1

Create a first task to represent current date:

      dataTable.addRows([
['', 'Hoy', new Date(2014,9,2), new Date(2014,9,2) ],

Create a function with jQuery to make this task longer:

function MarcarHoy (div, filas){
  $('#'+div+' text:contains("Hoy")').css('font-size','11px').attr('fill','#A6373C').prev().first().attr('height',filas*41+'px').attr('width','1px').attr('y','0');
  }

Call the function:

    chart.draw(dataTable, options);
  MarcarHoy('example1',23);
  google.visualization.events.addListener(chart, 'onmouseover', function(obj) {
    MarcarHoy('example1');
    });
}

The result:

Source: Viviendo en la Era de la Web 2.0