Bi-directional horizontal bar chart using ng charts-CodePudding

Does anyone know how to create a bi-directional bar chart using ng charts? See image for what I'm trying to achieve

I currently have a stacked bar chart, so is there a way of adapting this code to change it to a bi-directional chart instead?

Component.ts code:

  public chartData = [
    {
      data: [1, 5, 2, 2, 3],
      label: "Type 1",
      blob: "a",
    },
    {
      data: [5, 2, 3, 3, 2],
      label: "Type 2",
      blob: "a",
    },
  ];
  public chartLabels = [
    "Name 1",
    "Name 2",
    "Name 3",
    "Name 4",
    "Name 5",
  ];
  public chartPlugins = [];
  public chartOptions = {
    scales: {
      yAxes: [
        {
          display: true,
          stacked: true,
        },
      ],
      xAxes: [
        {
          display: true,
          stacked: true,
        },
      ],
    },
  };
  public chartColors = [
    {
      backgroundColor: "red",
      borderColor: "red",
    },
    {
      backgroundColor: "green",
      borderColor: "green",
    },
  ];

Html code:

  <canvas
    baseChart
    [datasets]="chartData"
    [labels]="chartLabels"
    [options]="chartOptions"
    [plugins]="chartPlugins"
    [colors]="chartColors"
    [legend]="true"
    [chartType]="'bar'">
  </canvas>

CodePudding user response：

In the picture, the values on the left of the center are negative. Instead in your code are positive both datasets values. I assume you want to maintain the data but in the chart to see positive values in both directions. If I have understood well, attached a sample.

const ctx = document.getElementById("myChart");
const myChart = new Chart(ctx, {
    type: 'horizontalBar',
    data: {
        labels: ['January', 'Fabruary', 'March', 'April', 'May', 'June', 'July'],
        datasets: [{
            label: 'user 1 online',
            data: [50, 35, 45, 47, 10, 3, 27],
            backgroundColor: 'rgba(40, 139, 170, 1)',
            borderWidth: 0,
            borderSkipped: false,
        },
        {
            label: 'user 2 online',
            data: [50, 35, 45, 47, 10, 3, 27],
            backgroundColor: 'orange',
            borderWidth: 0,
            borderSkipped: false,
            xAxisID: 'x2'
        }]
    },
    options: {
      scales: {
        yAxes: [{
          stacked: true,
          },
        ],
        xAxes: [{
          stacked: true,
          ticks: {
            callback(value) {
              return Math.abs(value);
            },
            min: -100,
            max: 100,
          }
        },
        {
          id: 'x2',
          type: 'linear',
          display: false,
          stacked: true,
          ticks: {
            min: -100,
            max: 100,
            reverse: true,
          }
        }]
      }
    }
});

.myChartDiv {
  max-width: 600px;
  max-height: 400px;
}

<script src="https://cdn.jsdelivr.net/npm/[email protected]"></script>
<html>
  <body>
    <div >
      <canvas id="myChart" width="600" height="400"/>
    </div>
  </body>
</html>

CodePudding user response：

You can use floating bars by specifying an array with 2 values instead of a single data point.

The 2 values are start and end so you can specify it as [0, actualValue]. Then you set the y axis to stacked and you will have that chart