标签未显示在ChartJS中

Question

I'm using ChartJS for my implementation of charts, but I notice that one of my graph's label is hidden. It is not showing its label above the bar. I've added a screenshot below for the comparison of two different bar graphs. The left graph shows the label even if it is on the very top but the other one is not showing. Please see my screenshot and code below.

function createChart(context, type, bgColor, bdColor, labels, actualData, options = {}){
    new Chart(context, {
        type: type,
        data: {
            labels: labels,
            datasets: [{
                label: "Actual",
                backgroundColor: bgColor,
                borderColor: bdColor,
                data: actualData,
            }]
        },

        options: options
    });
}


function getOptions(displayLegend = true){
    return {
      events: false,
         showTooltips: false,
         legend: {
             display: displayLegend
         },
         animation: {
             duration: 0,
             onComplete: function(){
                 var ctx = this.chart.ctx;
                 ctx.font = Chart.helpers.fontString(Chart.defaults.global.defaultFontFamily, 'normal', Chart.defaults.global.defaultFontFamily);
                 ctx.textAlign = 'center';
                 ctx.textBaseLine = 'bottom';
                 ctx.fillStyle = '#0b7707';

                 this.data.datasets.forEach(function(dataset){
                            console.log(dataset);
                     for(var i = 0; i < dataset.data.length; i++){
                         for(var key in dataset._meta){
                             var model = dataset._meta[key].data[i]._model;
                             ctx.fillText(dataset.data[i], model.x, model.y - 13);
                         }
                     }
                 });
             }
         }
     };
 }

Answer 1

This looks like a clear case of the datalabels going out of the canvas since the bar takes height dynamically as per the data values. You can set the max y-tick setting to solve this. Here is the jsfiddle -> https://jsfiddle.net/Luaf2tm4/5979/

Hope it helps!

var canvas = document.getElementById('myChart');
var data = {
  labels: ["January", "February", "March", "April", "May", "June"],
  datasets: [{
    label: "My First dataset",
    backgroundColor: "rgba(255,99,132,0.2)",
    borderColor: "rgba(255,99,132,1)",
    borderWidth: 2,
    hoverBackgroundColor: "rgba(255,99,132,0.4)",
    hoverBorderColor: "rgba(255,99,132,1)",
    data: [500, 2000, 800, 600, 950, 890],
  }]
};

function getOptions(displayLegend = false) {
  return {
    events: false,
    showTooltips: false,
    legend: {
      display: displayLegend
    },
    scales: {
      yAxes: [{
        display: true,
        stacked: true,
        ticks: {
            stepSize: 200,
          min: 0, // minimum value
          max: 2200 // maximum value, you can either hard code if you know your datainput, else computer the value through some logic i.e taking the max value from the dataset and adding some extra value to it. 
        }
      }]
    },
    animation: {
      duration: 0,
      onComplete: function() {
        var ctx = this.chart.ctx;
        ctx.font = Chart.helpers.fontString(Chart.defaults.global.defaultFontFamily, 'normal', Chart.defaults.global.defaultFontFamily);
        ctx.textAlign = 'center';
        ctx.textBaseLine = 'bottom';
        ctx.fillStyle = '#0b7707';

        this.data.datasets.forEach(function(dataset) {
          console.log(dataset);
          for (var i = 0; i < dataset.data.length; i++) {
            for (var key in dataset._meta) {
              var model = dataset._meta[key].data[i]._model;
              ctx.fillText(dataset.data[i], model.x, model.y - 10);
            }
          }
        });
      }
    }
  };
}

var myBarChart = Chart.Bar(canvas, {
  data: data,
  options: getOptions()
});