图表的最小值（Chart.js）

Question

I make a chart with Chart.js it's working but, I search for set a minimum value (for exemple 0) but I can't do it.

My code :

    <script type="text/javascript">
var NbCanvas = document.getElementById("NbTicketsChart");

Chart.defaults.global.defaultFontFamily = "Lato";
Chart.defaults.global.defaultFontSize = 18;

var densityData = {
    label: 'Nombre de tickets sur la semaine',
    data: [20, 25, 30, 25, 30, 35, 40],
    backgroundColor: '#336ca6'

};
var barChart = new Chart(NbCanvas, {
type: 'bar',
data: {
labels: ["J-1", "J-2", "J-3", "J-4", "J-5", "J-6", "J-7"],
datasets: [densityData],
options:{
        scales: {
            yAxes : [{
                ticks : {
                    max : 100,    
                    min : 0
                }
            }]
        }
    }
}

});
</script>

I tried with this :

  options:{
    scales: {
        yAxes : [{
            ticks : {
                max : 100,    
                min : 0
            }
        }]
    }
 }
}

Thanks for reading ! Arthur

Answer 1

This just frustrated me a fair bit. According to the documentation it seems your method should be working. I can only make it work by setting the scale after creating the chart, like below:

 <script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.8.0/Chart.bundle.min.js"></script> <canvas id="NbTicketsChart" width="50" height="50"></canvas> <script> var NbCanvas = document.getElementById("NbTicketsChart"); Chart.defaults.global.defaultFontFamily = "Lato"; Chart.defaults.global.defaultFontSize = 18; var densityData = { label: 'Nombre de tickets sur la semaine', data: [20, 25, 30, 25, 30, 35, 40], backgroundColor: '#336ca6' }; var barChart = new Chart(NbCanvas.getContext('2d'), { type: 'bar', data: { labels: ["J-1", "J-2", "J-3", "J-4", "J-5", "J-6", "J-7"], datasets: [densityData] }}); barChart.options.scales.yAxes[0] = {ticks: {min: 0, max: 100, stepValue: 20}} </script> 

In posting this i've also noticed it doesn't work when the canvas size is 400 by 400. 50 by 50 seems to work...

Answer 2

 <script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.8.0/Chart.bundle.min.js"></script> <canvas id="NbTicketsChart" width="50" height="50"></canvas> <script> var NbCanvas = document.getElementById("NbTicketsChart"); Chart.defaults.global.defaultFontFamily = "Lato"; Chart.defaults.global.defaultFontSize = 18; var densityData = { label: 'Nombre de tickets sur la semaine', data: [20, 25, 30, 25, 30, 35, 40], backgroundColor: '#336ca6' }; var barChart = new Chart(NbCanvas.getContext('2d'), { type: 'bar', data: { labels: ["J-1", "J-2", "J-3", "J-4", "J-5", "J-6", "J-7"], datasets: [densityData] }}); barChart.options.scales.yAxes[0] = {ticks: {min: 0, max: 100, stepValue: 20}} </script> 

That was the good solution but doesn't work with char.js 2.8 I use 2.7