Cannot read property 'transition' null chartjs

Issue

I have a dynamic data that is need to be put inside a for loop in order to display the data of interest. I tested putting animation into 0 from this issue and also try the same update() function.

This is my code below

barChartMonth() {
  let backgroundColor: any = [
    'rgba(255, 99, 132, 0.2)',
    'rgba(54, 162, 235, 0.2)',
    'rgba(255, 206, 86, 0.2)',
    'rgba(75, 192, 192, 0.2)',
    'rgba(153, 102, 255, 0.2)',
    'rgba(255, 159, 64, 0.2)',
    'rgba(255, 99, 132, 0.2)',
    'rgba(54, 162, 235, 0.2)',
    'rgba(255, 206, 86, 0.2)',
    'rgba(75, 192, 192, 0.2)',
    'rgba(153, 102, 255, 0.2)',
    'rgba(255, 159, 64, 0.2)'
  ];

  let borderColor: any = [
    'rgba(255,99,132,1)',
    'rgba(54, 162, 235, 1)',
    'rgba(255, 206, 86, 1)',
    'rgba(75, 192, 192, 1)',
    'rgba(153, 102, 255, 1)',
    'rgba(255, 159, 64, 1)',
    'rgba(255,99,132,1)',
    'rgba(54, 162, 235, 1)',
    'rgba(255, 206, 86, 1)',
    'rgba(75, 192, 192, 1)',
    'rgba(153, 102, 255, 1)',
    'rgba(255, 159, 64, 1)'
  ];


  this.barChart = new Chart(this.barCanvas.nativeElement, {
    type: 'bar',
    data: {
      labels: this.monthcostlabor,
    },
    options: {
      scales: {
        yAxes: [{
          ticks: {
            beginAtZero: true
          }
        }]
      }
    }
  });
  for(let bard = 0; bard < this.monthcostlabor.length; bard++){
    this.barChart.data.datasets.push({ label: this.monthcostlabor[bard], backgroundColor: backgroundColor[bard], borderColor: borderColor[bard], borderWidth: 1 });
  }
  this.barChart.data.datasets.forEach(element => {
    element.data.push(this.monthcostglobal)
  });
  this.barChart.update();
}

The code above dynamically choose color, hover and based on the data recorded. See for loop. Is there any other way to solve this issue?

Solution

A few of the glaring problems is how the length of backgroundColor and borderColor could be less than this.monthcostlabor leading to undefined values when loaded through the bard iterator.

Also, why cannot you loop within the constructor?

this.barChart = new Chart(this.barCanvas.nativeElement, {
  type: 'bar',
  data: {
    labels: this.monthcostlabor,
    datasets: this.monthcostlabor.map((elem,i) => ({ 
         label: elem, 
         backgroundColor: backgroundColor[(i % backgroundColor.length)], 
         borderColor: borderColor[(i % borderColor.length)], 
         borderWidth: 1, 
         data:[this.monthcostglobal] })); // the second push() can be included here?    
  },
  options: {
    scales: {
      yAxes: [{
        ticks: {
          beginAtZero: true
        }
      }]
    }
  }
});

/*
  for(let bard = 0; bard < this.monthcostlabor.length; bard++){
  this.barChart.data.datasets.push({ label: this.monthcostlabor[bard], backgroundColor: backgroundColor[bard], borderColor: borderColor[bard], borderWidth: 1 });
}
this.barChart.data.datasets.forEach(element => {
  element.data.push(this.monthcostglobal)
});
this.barChart.update(); */

Answered By - Dhananjai Pai