c3/src/api.tooltip.ts

D3-based reusable chart library

import { Chart } from './core'

Chart.prototype.tooltip = function() {}
Chart.prototype.tooltip.show = function(args) {
  var $$ = this.internal,
    targets,
    data,
    mouse = {}

  // determine mouse position on the chart
  if (args.mouse) {
    mouse = args.mouse
  } else {
    // determine focus data
    if (args.data) {
      data = args.data
    } else if (typeof args.x !== 'undefined') {
      if (args.id) {
        targets = $$.data.targets.filter(function(t) {
          return t.id === args.id
        })
      } else {
        targets = $$.data.targets
      }
      data = $$.filterByX(targets, args.x).slice(0, 1)[0]
    }
    mouse = data ? $$.getMousePosition(data) : null
  }

  // emulate mouse events to show
  $$.dispatchEvent('mousemove', mouse)

  $$.config.tooltip_onshow.call($$, data)
}
Chart.prototype.tooltip.hide = function() {
  // TODO: get target data by checking the state of focus
  this.internal.dispatchEvent('mouseout', 0)

  this.internal.config.tooltip_onhide.call(this)
}