Chart.js/docs/samples/advanced/programmatic-events.md

# Programmatic Event Triggers

```js chart-editor
// <block:hover:0>
function triggerHover(chart) {
  if (chart.getActiveElements().length > 0) {
    chart.setActiveElements([]);
  } else {
    chart.setActiveElements([
      {
        datasetIndex: 0,
        index: 0,
      }, {
        datasetIndex: 1,
        index: 0,
      }
    ]);
  }
  chart.update();
}
// </block:hover>

// <block:tooltip:1>
function triggerTooltip(chart) {
  const tooltip = chart.tooltip;
  if (tooltip.getActiveElements().length > 0) {
    tooltip.setActiveElements([], {x: 0, y: 0});
  } else {
    const chartArea = chart.chartArea;
    tooltip.setActiveElements([
      {
        datasetIndex: 0,
        index: 2,
      }, {
        datasetIndex: 1,
        index: 2,
      }
    ],
    {
      x: (chartArea.left + chartArea.right) / 2,
      y: (chartArea.top + chartArea.bottom) / 2,
    });
  }

  chart.update();
}
// </block:tooltip>

// <block:actions:2>
const actions = [
  {
    name: 'Trigger Hover',
    handler: triggerHover
  },
  {
    name: 'Trigger Tooltip',
    handler: triggerTooltip
  }
];
// </block:actions>

// <block:setup:4>
const DATA_COUNT = 7;
const NUMBER_CFG = {count: DATA_COUNT, min: -100, max: 100};

const labels = Utils.months({count: 7});
const data = {
  labels: labels,
  datasets: [
    {
      label: 'Dataset 1',
      data: Utils.numbers(NUMBER_CFG),
      borderColor: Utils.CHART_COLORS.red,
      backgroundColor: Utils.transparentize(Utils.CHART_COLORS.red, 0.5),
      hoverBorderWidth: 5,
      hoverBorderColor: 'green',
    },
    {
      label: 'Dataset 2',
      data: Utils.numbers(NUMBER_CFG),
      borderColor: Utils.CHART_COLORS.blue,
      backgroundColor: Utils.transparentize(Utils.CHART_COLORS.blue, 0.5),
      hoverBorderWidth: 5,
      hoverBorderColor: 'green',
    }
  ]
};
// </block:setup>

// <block:config:3>
const config = {
  type: 'bar',
  data: data,
  options: {
  },
};
// </block:config>

module.exports = {
  actions: actions,
  config: config,
};
```

## API
* [Chart](../../api/classes/Chart.md)
  * [`setActiveElements`](../../api/classes/Chart.md#setactiveelements)
* [TooltipModel](../../api/interfaces/TooltipModel.html)
  * [`setActiveElements`](../../api/interfaces/TooltipModel.html#setactiveelements)

## Docs
* [Bar](../../charts/bar.html)
    * [Interactions (`hoverBorderColor`)](../../charts/bar.html#interactions)
* [Interactions](../../configuration/interactions.html)
* [Tooltip](../../configuration/tooltip.html)