Chart.js - Increase spacing between legend and chart

问题

I have a bar chart where I have drawn 3 vertical lines, each with it's own label at the top. I would like those labels to be above the top of the y-axis (above the 30% line in the example) but below the legend. I can't figure out how to increase the space between the top legend and the chart such that I can have my vertical line labels (15, 24 & 33) be off of the chart itself but below the legend. Any ideas?

回答1:

Unfortunately, since there is no config option to handle this the only way you can achieve the desired result is to extend Chart.Legend and implement the afterFit() callback.

Here is a quick codepen showing how to do just that. To change the spacing, just change the value in line 9 (currently set to 50). Also, this of course only works with the legend at the top. Hopefully, the example is clear enough for you to modify in case you want to move your legend elsewhere.

回答2:

If you want do increase spacing in all charts you can put this code before creating :

Chart.Legend.prototype.afterFit = function() {
    this.height = this.height + 50;
};

Of course, I don't try but i think you can change it (or copy the original Chart object before, to keep the original padding).

Bye,

回答3:

If you want to apply padding below legend for some charts only in your app:

ChartJS >= 2.1.0

Chart.plugins.register({
  id: 'paddingBelowLegends',
  beforeInit: function(chart, options) {
    chart.legend.afterFit = function() {
      this.height = this.height + 50;
    };
  }
});

// ----------------------------------
// disable the plugin only for charts
// where you DO NOT WANT the padding
// ----------------------------------

// for raw ChartJS use:
var chart = new Chart(ctx, {
  config: {
    plugins: {
      paddingBelowLegends: false
    }
  }
});

// for angular-chartjs:
$scope.myChart.options.plugins = { paddingBelowLegends: false }
// then in template:
// <canvas class="chart ..." chart-options="myChart.options" ... />

ChartJS >= 2.5.0

Specific plugins for each chart are supported, it should be possible to do:

var chart = new Chart(ctx, {
  plugins: [{
    beforeInit: function(chart, options) {
      chart.legend.afterFit = function() {
        this.height = this.height + 50;
      };
    }
  }]
});

See ChartJS documentation + inspired by this other answer

回答4:

This helped me after 2 days of research.

Chart.Legend.prototype.afterFit = function() {
    this.height = this.height + 50;
};

update this in module.ts file

回答5:

I'm using react-chartjs-2 (but this is just a port and uses the same configurations object) and I was able to achieve that by changing the labels configuration nested on legend configuration:

chartOptions = {
  legend: {
    labels: {
      padding: 50 -> this one.
    }
  },

You can check the property description here: https://www.chartjs.org/docs/latest/configuration/legend.html

Hope it helps.

回答6:

I have tried the above approaches on my react(react-chartjs-2) project but no luck. Here I have one different approach like creating custom legends outside the chart. so you can get more control over it

1. Hide default legend
2. Get legend object using any ref method.
3. Loop and make a custom legend using html and css.
4. Sample codesanbox

I am aware that OP is not about reactjs component, but as it is a common issue it will help someone.

Orginal reference

.

来源：https://stackoverflow.com/questions/42585861/chart-js-increase-spacing-between-legend-and-chart