drawchart = calendarHeatmap.drawChart = function () {
if (calendarHeatmap.overview === 'global') {
calendarHeatmap.drawGlobalOverview();
} else if (calendarHeatmap.overview === 'year') {
calendarHeatmap.drawYearOverview();
} else if (calendarHeatmap.overview === 'month') {
calendarHeatmap.drawMonthOverview();
} else if (calendarHeatmap.overview === 'week') {
calendarHeatmap.drawWeekOverview();
} else if (calendarHeatmap.overview === 'day') {
calendarHeatmap.drawDayOverview();
}
}