I wonder if I can set the lines to be hidden in chartjs datasets->segment
like this:
const down = (ctx, value) => ctx.p0.parsed.y > ctx.p1.parsed.y ? value : undefined;
const up = (ctx, value) => ctx.p0.parsed.y < ctx.p1.parsed.y ? value : undefined;
segment: {
borderColor: ctx => down(ctx , 'rgb(192,75,75)') || up(ctx, 'rgb(0,255,0)'),
borderDash: ctx => down(ctx, [5,5]),
hidden: ctx => down(ctx,false),
}
maybe i should use other styling element
>Solution :
You can set the color to transparent – I tried to use the borderwidth, but that did not seem to work as well as transparent did:
const ctx = document.getElementById('myChart').getContext('2d');
const data = {
labels: Array.from({
length: 10
}, (_, i) => i), // x-axis labels
datasets: [{
label: 'Sample Data',
data: [0, 2, 1, 3, 2, 4, 3, 5, 4, 6], // Sample data with up and down trends
borderColor: 'rgb(0,255,0)', // Default color for visible (upward) segments
segment: {
borderColor: ctx => {
const isDown = ctx.p0.parsed.y > ctx.p1.parsed.y;
return isDown ? 'rgba(0,0,0,0)' : 'rgb(0,255,0)'; // Transparent for down, green for up
}
},
fill: false,
}]
};
const config = {
type: 'line',
data: data,
options: {
responsive: true,
plugins: {
legend: {
display: true
}
},
scales: {
x: {
title: {
display: true,
text: 'X-axis'
}
},
y: {
title: {
display: true,
text: 'Y-axis'
}
}
}
}
};
new Chart(ctx, config);<script src="https://cdn.jsdelivr.net/npm/chart.js"></script>
<canvas id="myChart" width="600" height="400"></canvas>