Google Chart, how to move annotation on top of columns

Question

I'm using Google Chart's stacked column chart, what i wanna achieve is to display the total on top of each column and i'm using annotation for this. As you look at the image, somehow only the annotation on the 5th column (1,307.20) is working as expected.

As i investigate , this seem like a bug of Google Chart , this bug can be explained like below

[[Date, Car, Motobike, {role: :annotation}],
[June 2015, 500, 0, 500],
[Feb 2015, 500, 600, 1100]]
[March 2015, 700, 0, 700],

With the above data, the annotation for Feb 2015 is the only which is displayed correctly , the other 2 do not since the last value of then is 0 , when I change the last value to 1 for June and March , the annotation is displayed correctly.

Then I think of a work around is to always display the "non-zero" data on top , and here's the result:

The annotations are moved on top properly , but as you can see, it's located within the column and what i want to achieve is to move it on top of the column .

I'm stuck with this for a while , Google Documentation doesn't help much with this case. Any help would be highly appreciated

Answer 1

I had the same problem, some of my series had 0 as my last value so the label would show on the X Axis instead of at the top. With dynamic data it would be a real challenge to ensure the last value was never 0. @dlaliberte gave me a hint where to start with this comment:

"As a workaround, you might consider using a ComboChart with an extra series to draw a point at the top of each column stack. You'll have to compute the total of the other series yourself to know where to put each point."

I found a combo chart from google's gallery and opened jsfiddle to see what I could do. I left the data mostly, but changed the series name labels and made the numbers a little simpler. Don't get caught up on the purpose of the graph the data is regardless, I just wanted to figure out how to get my annotation to the top of the graph even when the last column was 0 (https://jsfiddle.net/L5wc8rcp/1/):

function drawVisualization() {
    // Some raw data (not necessarily accurate)
    var data = google.visualization.arrayToDataTable([
        ['Month', 'Bolivia', 'Ecuador', 'Madagascar', 'Papua New Guinea', 'Rwanda', 'Total', {type: 'number', role: 'annotation'}],
        ['Application', 5, 2, 2, 8, 0, 17, 17],
        ['Friend', 4, 3, 5, 6, 2, 20, 20],
        ['Newspaper', 6, 1, 0, 2, 0, 9, 9],
        ['Radio', 8, 0, 8, 1, 1, 18, 18],
        ['No Referral', 2, 2, 3, 0, 6, 13, 13]
    ]);

    var options = {
        isStacked: true,
        title : 'Monthly Coffee Production by Country',
        vAxis: {title: 'Cups'},
        hAxis: {title: 'Month'},
        seriesType: 'bars',
        series: {5: {type: 'line'}},
    };

    var chart = new google.visualization.ComboChart(document.getElementById('chart_div'));
    chart.draw(data, options);
}

That produced this graph, which is a great start:

As you can see since series 5 (our Total of the other series) is a type: 'line', so it will always point to the top of the stack. Now, I didn't necessarily want the line in my chart, since it was not used to compare continuous horizontal totals, so I updated series 5 with lineWidth: 0, and then made the title of that category '' so that it wouldn't be included in the legend as a stack (https://jsfiddle.net/Lpgty7rq/):

function drawVisualization() {
    // Some raw data (not necessarily accurate)
    var data = google.visualization.arrayToDataTable([
        ['Month', 'Bolivia', 'Ecuador', 'Madagascar', 'Papua New Guinea', 'Rwanda', '', {type: 'number', role: 'annotation'}],
        ['Application', 5, 2, 2, 8, 0, 17, 17],
        ['Friend', 4, 3, 5, 6, 2, 20, 20],
        ['Newspaper', 6, 1, 0, 2, 0, 9, 9],
        ['Radio', 8, 0, 8, 1, 1, 18, 18],
        ['No Referral', 2, 2, 3, 0, 6, 13, 13]
    ]);

    var options = {
        isStacked: true,
        title : 'Monthly Coffee Production by Country',
        vAxis: {title: 'Cups'},
        hAxis: {title: 'Month'},
        seriesType: 'bars',
        series: {5: {type: 'line', lineWidth: 0}}, 
    };

   var chart = new google.visualization.ComboChart(document.getElementById('chart_div'));
   chart.draw(data, options);
}

And Voila!