When using GeoChart, only the row index is returned for the column, with null being returned for the column itself.
To access the country name, always refer to column 0 (zero) as it will contain the country names.
Below is a functional code snippet:
google.charts.load('current', {
'packages':['geochart'],
// Note: you will need to get a mapsApiKey for your project.
// See: https://developers.google.com/chart/interactive/docs/basic_load_libs#load-settings
'mapsApiKey': 'AIzaSyD-9tSrke72PouQMnMX-a7eZSW0jkFMBWY'
});
google.charts.setOnLoadCallback(drawRegionsMap);
function drawRegionsMap() {
var data = google.visualization.arrayToDataTable([
['Country', 'Popularity'],
['Germany', 200],
['United States', 300],
['Brazil', 400],
['Canada', 500],
['France', 600],
['RU', 700]
]);
var options = {};
var chart = new google.visualization.GeoChart(document.getElementById('chart_div'));
google.visualization.events.addListener(chart, 'select', selectHandler);
function selectHandler() {
var selectedItem = chart.getSelection();
if (selectedItem.length > 0) {
console.log(data.getValue(selectedItem[0].row, 0));
}
}
chart.draw(data, options);
}
<script src="https://www.gstatic.com/charts/loader.js"></script>
<div id="chart_div"></div>