chartjs-plugin-funnel-label

Plugin for Chart.js to add labels between columns to show the % progress in the same dataset. Chart.js 2.6.0 or above required.

Written by Albert Gonzalez and released under the Unlicense.

Some improvements (border color, border gradient color and label text) thanks to Pawel M.

See it in action!

Starting

Add the chartjs-plugin-funnel-label.js and use the funnel_labels options to enable the plugin and override the default values.

It works only in bar charts with one dataset and will show the % difference between each bar.

new Chart($("#chart"), {
  type: 'bar',
  data: {
    labels: ["Alpha Value", "Beta Value", "Charlie Value", "Delta Value"],
    datasets: [{
      label: 'First Dataset',
      data: [555, 302, 175, 50],
      backgroundColor: "rgba(75, 192, 192, 1)"
    }]
  },
  options: {
    scales: {
      yAxes: [{
        ticks: {
          beginAtZero: true
        }
      }],
      xAxes: [{
        barPercentage: 0.3
      }]
    },
    funnel_labels: {
      enabled: true,
      background_color: "red"
    }
  }
});

Current options

They're set in the label_options object with these default values:

label_options: {
  enabled: false,
  font_style: "normal",
  font_family: "Arial",
  font_color: "white",
  background_color: "#FFBA4B",
  rectangle_width_scale_factor: 5,
  show_zeros: true,
  min_width_upper_label: 150,
  allow_upper_label: true,
  force_upper_label: false,
  border_color: "#FFBA4B",
  border_colors: [],
  sub_text: null,
  sub_text_style: "normal",
  text_align: "center",
  label_centered: true
}

rectangle_width_scale_factor

width for each label rectangle = width between two bars / rectangle_width_scale_factor

show_zeros

If true will show the labels with a 0% value (otherwise will hide them).

min_width_upper_label

If the width between two bars is smaller than this value the labels will appear over them.

allow_upper_label

If set to false, the labels over the bars won't appear (it won't draw anything).

force_upper_label

If true will always show the labels over the bars (this will override the allow_upper_label option).

border_color

Single color for the borders.

border_colors

An array of colors to create a gradient between them.

sub_text

Optional label text

sub_text_style

Style for the text

text_align

Alignment for the text

label_centered

If true will center the label on the bar (vertically).

Known issues

• The plugin can't handle more than one dataset and it just won't draw anything.