Area Charts
Both line and radar charts support a fill option on the dataset object which can be used to create area between two datasets or a dataset and a boundary, i.e. the scale origin, start or end (see filling modes).
Note: this feature is implemented by the
fillerplugin.
Filling modes
| Mode | Type | Values | 
|---|---|---|
| Absolute dataset index 1 | Number | 1,2,3, ... | 
| Relative dataset index 1 | String | '-1','-2','+1', ... | 
| Boundary 2 | String | 'start','end','origin' | 
| Disabled 3 | Boolean | false | 
1 dataset filling modes have been introduced in version 2.6.0
2 prior version 2.6.0, boundary values was'zero','top','bottom'(deprecated)
3 for backward compatibility,fill: true(default) is equivalent tofill: 'origin'
Example
new Chart(ctx, {
    data: {
        datasets: [
            {fill: 'origin'},      // 0: fill to 'origin'
            {fill: '+2'},          // 1: fill to dataset 3
            {fill: 1},             // 2: fill to dataset 1
            {fill: false},         // 3: no fill
            {fill: '-2'}           // 4: fill to dataset 2
        ]
    }
})
Configuration
| Option | Type | Default | Description | 
|---|---|---|---|
| plugins.filler.propagate | Boolean | true | Fill propagation when target is hidden | 
propagate
Boolean (default: true)
If true, the fill area will be recursively extended to the visible target defined by the fill value of hidden dataset targets:
Example
new Chart(ctx, {
    data: {
        datasets: [
            {fill: 'origin'},   // 0: fill to 'origin'
            {fill: '-1'},       // 1: fill to dataset 0
            {fill: 1},          // 2: fill to dataset 1
            {fill: false},      // 3: no fill
            {fill: '-2'}        // 4: fill to dataset 2
        ]
    },
    options: {
        plugins: {
            filler: {
                propagate: true
            }
        }
    }
})
propagate: true:
- if dataset 2 is hidden, dataset 4 will fill to dataset 1
- if dataset 2 and 1 are hidden, dataset 4 will fill to 'origin'
propagate: false:
- if dataset 2 and/or 4 are hidden, dataset 4 will not be filled