Custom Tooltip Content
This sample shows how to use the tooltip callbacks to add additional content to the tooltip.
const config = {
type: 'line',
data: data,
options: {
interaction: {
intersect: false,
mode: 'index',
},
plugins: {
tooltip: {
callbacks: {
footer: footer,
}
}
}
}
};
const DATA_COUNT = 7;
const NUMBER_CFG = {count: DATA_COUNT, min: -100, max: 100, decimals: 0};
const data = {
labels: Utils.months({count: DATA_COUNT}),
datasets: [
{
label: 'Dataset 1',
data: Utils.numbers(NUMBER_CFG),
fill: false,
borderColor: Utils.CHART_COLORS.red,
backgroundColor: Utils.transparentize(Utils.CHART_COLORS.red, 0.5),
},
{
label: 'Dataset 2',
data: Utils.numbers(NUMBER_CFG),
fill: false,
borderColor: Utils.CHART_COLORS.blue,
backgroundColor: Utils.transparentize(Utils.CHART_COLORS.blue, 0.5),
},
]
};
const footer = (tooltipItems) => {
let sum = 0;
tooltipItems.forEach(function(tooltipItem) {
sum += tooltipItem.parsed.y;
});
return 'Sum: ' + sum;
};
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