# Async drilldown (Column example)

> WestCoast Charts 1.1.5, release, public Core release, on npm. HTML: https://westcoast-charts.com/gallery/column/column-drilldown-async/ · Index for agents: https://westcoast-charts.com/llms.txt

Drilling loads the next level asynchronously; a loading bar shows while it arrives.

- Chart type: `bar` (Bar)
- Collection: Column · Column
- Raw configuration: https://westcoast-charts.com/gallery-src/column/column-drilldown-async.js
- Standalone example: https://westcoast-charts.com/embed/samples/wcc/gallery/column/column-drilldown-async.html

## Setup

```js
import WestCoastCharts from 'west-coast-charts'
import types from 'west-coast-charts/types'
import drilldown from 'west-coast-charts/features/drilldown'

WestCoastCharts.use(types).use(drilldown)
```

## Options

```js
const options = {
  chart: {
    height: 380,
    fontFamily: "Inter, Geist, \"IBM Plex Sans\", system-ui, sans-serif",
    type: "bar",
    toolbar: {
      show: false
    }
  },
  series: [
    {
      name: "Sales",
      data: [
        {
          x: "Hardware",
          y: 320,
          drilldown: "Hardware"
        },
        {
          x: "Software",
          y: 540,
          drilldown: "Software"
        },
        {
          x: "Services",
          y: 210,
          drilldown: "Services"
        }
      ]
    }
  ],
  plotOptions: {
    bar: {
      borderRadius: 4,
      columnWidth: "45%"
    }
  },
  dataLabels: {
    enabled: false
  },
  drilldown: {
    enabled: true,
    onDrillDown: ({ id }) => fetchLevel(id)
  },
  title: {
    text: "Sales by division (click to load)"
  },
  theme: {
    mode: "light",
    preset: "coastal"
  }
}

const chart = new WestCoastCharts(document.querySelector('#chart'), options)
await chart.render()
```

## Verify

- Text check (Library 1.1.5): load `west-coast-charts/agent/describe` and call `chart.describe({ format: "json" })` for the actual drawn state. The live reader is on this example’s HTML page.
- Command line (Public agent tools 0.2.3, tested with Library 1.1.5; available from the versioned GitHub release and npm, https://westcoast-charts.com/docs/cli/index.md): `wcc chart export column-column-drilldown-async.json --out column-column-drilldown-async.svg --with-table` (save the options above as JSON first)