mark.label 可以通过 channel 设置值 #4781

/**
 * A recreation of this demo: https://vega.github.io/vega-lite/examples/layer_precipitation_mean.html
 */
import { Chart } from '@antv/g2';

const chart = new Chart({
  container: 'container',
  autoFit: true,
});

chart.data({
  type: 'fetch',
  value: 'https://assets.antv.antgroup.com/g2/seattle-weather.json',
});

chart
  .interval()
  .transform({ type: 'groupX', y: 'mean' })
  .encode('x', (d) => new Date(d.date).getUTCMonth())
  .encode('y', 'precipitation')
  .scale('y', { tickCount: 5, domainMax: 6 })
  .tooltip({ channel: 'y', valueFormatter: '.2f' });

chart
  .lineY()
  .transform({ type: 'groupX', y: 'mean' })
  .encode('y', 'precipitation')
  .style('stroke', '#F4664A')
  .style('strokeOpacity', 1)
  .style('lineWidth', 2)
  .label({
    text: { channel: 'y' }, // 使用 y 通道的值
  });