Google Visualization JSON PHP - json

Question

I spent the whole day trying to get a pie chart with Google Charts.
I am getting my results from a MySQL Database using PHP.
The result is a JSON which looks like this:
stdClass Object
(
[cols] => Array
(
[0] => stdClass Object
(
[label] => Firma
[type] => string
)
[1] => stdClass Object
(
[label] => Zeit
[type] => number
)
)
[rows] => Array
(
[0] => stdClass Object
(
[Firma] => Firma1
[Zeit] => 60
)
[1] => stdClass Object
(
[Firma] => Firma2
[Zeit] => 40
)
)
)
Javascript Code looks like this:
google.charts.load('current', {'packages':['corechart']});
google.charts.setOnLoadCallback(drawChart);
function drawChart() {
var data = new google.visualization.DataTable(<?=$jsongesamtzeiten;?>);
//data.addColumn('string', 'Firma');
//data.addColumn('number', 'Zeit');
//data.addRows([ ['Firma1',40], ['Firma2',60] ]);
var options = {
title: 'Arbeitsverteilung gesamt',
colors: ['#3B2BC1', '#7EBB58'],
width: 600,
height: 400,
backgroundColor: { stroke: "#CCC", strokeWidth: 2, fill: "#f5f5f5" }
};
var chart = new google.visualization.PieChart(document.getElementById('piechart'));
chart.draw(data, options);
};
I get a:
Cannot read property '1' of undefined
as reply.
If I uncomment the data.addColumn and data.addRows and remove the <?=$jsongesamtzeiten;?> it works. But that's not what I want, because I want to recieve the data from a MySQL-database.
I did many google-searches and found some similiar questions here, but nothing helped me.
Thanks.

Answer 1

I believe the problem lies in the JSON rows column value keys.
It appears you're naming the object keys according to their column labels.
However, the key for a value should simply be v
See the first example under the DataTable class reference
Try changing the JSON as follows...
stdClass Object
(
[cols] => Array
(
[0] => stdClass Object
(
[label] => Firma
[type] => string
)
[1] => stdClass Object
(
[label] => Zeit
[type] => number
)
)
[rows] => Array
(
[0] => stdClass Object
(
[v] => Firma1
[v] => 60
)
[1] => stdClass Object
(
[v] => Firma2
[v] => 40
)
)
)
Also, since you're already including the column and row definitions in your JSON,
you will not need to use data.addColumn or data.addRows
only need...
var data = new google.visualization.DataTable(<?=$jsongesamtzeiten;?>);
(once the format is correct)