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Getting Started

vue-chartjs is a wrapper for Chart.js in vue. You can easily create reuseable chart components.

Supports Chart.js v3 and v2.

Introduction

vue-chartjs lets you use Chart.js without much hassle inside Vue. It's perfect for people who need simple charts up and running as fast as possible.

It abstracts the basic logic but exposes the Chart.js object to give you maximal flexibility.

:::tip Need an API to fetch data? Please consider Cube, an open-source API for data apps. :::

Installation

You can install vue-chartjs over yarn or npm or pnpm. However, you also need to add chart.js as a dependency to your project because Chart.js is a peerDependency. This way you can have full control over the versioning of Chart.js.

pnpm add vue-chartjs chart.js
# or
yarn add vue-chartjs chart.js
# or
npm i vue-chartjs chart.js

Integration

Every chart type that is available in Chart.js is exported as a named component and can be imported as such. These components are normal Vue components.

The idea behind vue-chartjs is to provide easy-to-use components, with maximal flexibility and extensibility.

Creating your first Chart

First, you need to import the base chart.

import { Bar } from 'vue-chartjs'

For Vue 2 projects, you need to import from vue-chartjs/legacy.

import { Bar } from 'vue-chartjs/legacy'

Check out the official Chart.js docs to see the object structure you need to provide.

Just create your own component.

BarChart.vue

<template>
  <Bar
    :chart-options="chartOptions"
    :chart-data="chartData"
    :chart-id="chartId"
    :dataset-id-key="datasetIdKey"
    :plugins="plugins"
    :css-classes="cssClasses"
    :styles="styles"
    :width="width"
    :height="height"
  />
</template>

<script>
import { Bar } from 'vue-chartjs'
import { Chart as ChartJS, Title, Tooltip, Legend, BarElement, CategoryScale, LinearScale } from 'chart.js'

ChartJS.register(Title, Tooltip, Legend, BarElement, CategoryScale, LinearScale)

export default {
  name: 'BarChart',
  components: { Bar },
  props: {
    chartId: {
      type: String,
      default: 'bar-chart'
    },
    datasetIdKey: {
      type: String,
      default: 'label'
    },
    width: {
      type: Number,
      default: 400
    },
    height: {
      type: Number,
      default: 400
    },
    cssClasses: {
      default: '',
      type: String
    },
    styles: {
      type: Object,
      default: () => {}
    },
    plugins: {
      type: Object,
      default: () => {}
    }
  },
  data() {
    return {
      chartData: {
        labels: [ 'January', 'February', 'March' ],
        datasets: [ { data: [40, 20, 12] } ]
      },
      chartOptions: {
        responsive: true
      }
    }
  }
}
</script>

or in TypeScript:

BarChart.ts

import { defineComponent, h, PropType } from 'vue'
import { Bar } from 'vue-chartjs'
import { Chart as ChartJS, Title, Tooltip, Legend, BarElement, CategoryScale, LinearScale, PluginOptionsByType } from 'chart.js'

ChartJS.register(Title, Tooltip, Legend, BarElement, CategoryScale, LinearScale)

export default defineComponent({
  name: 'BarChart',
  components: { Bar },
  props: {
    chartId: {
      type: String,
      default: 'bar-chart'
    },
    width: {
      type: Number,
      default: 400
    },
    height: {
      type: Number,
      default: 400
    },
    cssClasses: {
      default: '',
      type: String
    },
    styles: {
      type: Object as PropType<Partial<CSSStyleDeclaration>>,
      default: () => {}
    },
    plugins: {
      type: Object as PropType<PluginOptionsByType<'bar'>>,
      default: () => {}
    }
  },
  setup(props) {
    const chartData = {
      labels: [ 'January', 'February', 'March' ],
      datasets: [ { data: [40, 20, 12] } ]
    }

    const chartOptions = { responsive: true }

    return () =>
      h(Bar, {
        chartData,
        chartOptions,
        chartId: props.chartId,
        width: props.width,
        height: props.height,
        cssClasses: props.cssClasses,
        styles: props.styles,
        plugins: props.plugins
      })
  }
})

Use it in your vue app:

App.vue

<template>
  <BarChart />
</template>

<script>
import BarChart from 'path/to/component/BarChart'

export default {
  name: 'App',
  components: { BarChart }
}
</script>

Updating Charts

v4 charts have data change watcher and options change watcher by default. v4 will update or re-render the chart if new data or new options is passed. Mixins have been removed.

<template>
  <Bar :chart-data="chartData" :chart-options="chartOptions" />
</template>

<script>
// DataPage.vue
import { Bar } from 'vue-chartjs'
import { Chart as ChartJS, Title, Tooltip, Legend, BarElement, CategoryScale, LinearScale } from 'chart.js'

ChartJS.register(Title, Tooltip, Legend, BarElement, CategoryScale, LinearScale)

export default {
  name: 'BarChart',
  components: { Bar },
  computed: {
      chartData() { return /* mutable chart data */ },
      chartOptions() { return /* mutable chart options */ }
    }
}
</script>

Access to Chart instance

You can get access to chart instance via template refs.

<template>
  <BarChart ref="bar" />
</template>

In Vue3 projects:

const chartInstance = this.$refs.bar.chart

In Vue2 projects:

const chartInstance = this.$refs.bar.getCurrentChart

Also you can get access to updateChart function

this.$refs.bar.updateChart()

Events

Charts will emit events if the data changes. You can listen to them in the chart component. The following events are available:

  • chart:rendered - if the chart object instance rendered
  • chart:destroyed - if the chart object instance removed
  • chart:updated - if the update handler performs an update instead of a re-render
  • labels:updated - if new labels were set

chartjs-plugin-annotation

When using chartjs-plugin-annotation and Vue 2 simultaneously, you will not be able to place multiple reactive charts on one page.

Examples

Chart with props

Your goal should be to create reusable chart components. For this purpose, you should utilize Vue.js props to pass in chart options and chart data. This way, the parent component itself does not hold an opinion about fetching data and is only for presentation.

<template>
  <Bar :chart-data="chartData" :chart-options="chartOptions" />
</template>

<script>
import { Bar } from 'vue-chartjs'
import { Chart as ChartJS, Title, Tooltip, Legend, BarElement, CategoryScale, LinearScale } from 'chart.js'

ChartJS.register(Title, Tooltip, Legend, BarElement, CategoryScale, LinearScale)

export default {
  name: 'BarChart',
  components: { Bar },
  props: {
    chartData: {
        type: Object,
        required: true
      },
    chartOptions: {
      type: Object,
      default: () => {}
    }
  }
}
</script>

Chart with local data

You can handle your chart data directly in your parent component.

<template>
  <Bar :chart-data="chartData" />
</template>

<script>
import { Bar } from 'vue-chartjs'
import { Chart as ChartJS, Title, Tooltip, Legend, BarElement, CategoryScale, LinearScale } from 'chart.js'

ChartJS.register(Title, Tooltip, Legend, BarElement, CategoryScale, LinearScale)

export default {
  name: 'BarChart',
  components: { Bar },
  data() {
    return {
      chartData: {
        labels: [ 'January', 'February', 'March'],
        datasets: [
          {
            label: 'Data One',
            backgroundColor: '#f87979',
            data: [40, 20, 12]
          }
        ]
      }
    }
  }
}
</script>

Chart with API data

A common pattern is to use an API to retrieve your data. However, there are some things to keep in mind. The most common problem is that you mount your chart component directly and pass in data from an asyncronous API call. The problem with this approach is that Chart.js tries to render your chart and access the chart data syncronously, so your chart mounts before the API data arrives.

To prevent this, a simple v-if is the best solution.

Create your chart component with a data prop and options prop, so we can pass in our data and options from a container component.

<template>
  <div class="container">
    <Bar v-if="loaded" :chart-data="chartData" />
  </div>
</template>

<script>
import { Bar } from 'vue-chartjs'
import { Chart as ChartJS, Title, Tooltip, Legend, BarElement, CategoryScale, LinearScale } from 'chart.js'

ChartJS.register(Title, Tooltip, Legend, BarElement, CategoryScale, LinearScale)

export default {
  name: 'BarChart',
  components: { Bar },
  data: () => ({
    loaded: false,
    chartData: null
  }),
  async mounted () {
    this.loaded = false

    try {
      const { userlist } = await fetch('/api/userlist')
      this.chartdata = userlist

      this.loaded = true
    } catch (e) {
      console.error(e)
    }
  }
}
</script>

Chart with dynamic styles

You can set responsive: true and pass in a styles object which gets applied as inline styles to the outer <div>. This way, you can change the height and width of the outer container dynamically, which is not the default behaviour of Chart.js. It is best to use computed properties for this.

::: warning You need to set position: relative :::

<template>
  <div>
    <Bar :styles="myStyles"/>
  </div>
</template>

<script>
import { Bar } from 'vue-chartjs'
import { Chart as ChartJS, Title, Tooltip, Legend, BarElement, CategoryScale, LinearScale } from 'chart.js'

ChartJS.register(Title, Tooltip, Legend, BarElement, CategoryScale, LinearScale)

export default {
  name: 'BarChart',
  components: { Bar },
  computed: {
    myStyles () {
      return {
        height: `${/* mutable height */}px`,
        position: 'relative'
      }
    }
  }
}
</script>

Custom / New Charts

Sometimes you need to extend the default Chart.js charts. There are a lot of examples on how to extend and modify the default charts. Or, you can create your own chart type.

In vue-chartjs, you can do this pretty much the same way:

// 1. Import Chart.js so you can use the global Chart object
import { Chart } from 'chart.js'
// 2. Import the `generateChart()` method to create the vue component.
import { generateChart } from 'vue-chartjs'
// 3. Import needed controller from Chart.js
import { LineController } from 'chart.js'

// 3. Extend one of the default charts
// http://www.chartjs.org/docs/latest/developers/charts.html
class LineWithLineController extends LineController { /* custom magic here */}

// 4. Generate the vue-chartjs component
// The first argument is the chart-id, the second the chart type, third is the custom controller
const CustomLine = generateChart('custom-line', 'line', LineWithLineController)

// 5. Extend the CustomLine Component just like you do with the default vue-chartjs charts.

export default {
  components: { CustomLine }
}

Resources

Here are some resources, such as tutorials, on how to use vue-chartjs: