Tạo Line Chart thật dễ dàng với Chartjs

Chia sẻ

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1. HTML

<script src="https://www.chartjs.org/dist/2.9.3/Chart.min.js"></script>
<script src="https://www.chartjs.org/samples/latest/utils.js"></script>

<div style="width:80%; margin-left: auto; margin-right: auto;">
		<canvas id="canvas"></canvas>

		<br><br>
		<button id="randomizeData">Randomize Data</button>
		<button id="addDataset">Add Dataset</button>
		<button id="removeDataset">Remove Dataset</button>
		<button id="addData">Add Data</button>
		<button id="removeData">Remove Data</button>
		<br><br>
	</div>

2. CSS

canvas{
		-moz-user-select: none;
		-webkit-user-select: none;
		-ms-user-select: none;
	}

3. JAVASCRIPT

var MONTHS = ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December'];
		var config = {
			type: 'line',
			data: {
				labels: ['January', 'February', 'March', 'April', 'May', 'June', 'July'],
				datasets: [{
					label: 'My First dataset',
					backgroundColor: window.chartColors.red,
					borderColor: window.chartColors.red,
					data: [
						randomScalingFactor(),
						randomScalingFactor(),
						randomScalingFactor(),
						randomScalingFactor(),
						randomScalingFactor(),
						randomScalingFactor(),
						randomScalingFactor()
					],
					fill: false,
				}, {
					label: 'My Second dataset',
					fill: false,
					backgroundColor: window.chartColors.blue,
					borderColor: window.chartColors.blue,
					data: [
						randomScalingFactor(),
						randomScalingFactor(),
						randomScalingFactor(),
						randomScalingFactor(),
						randomScalingFactor(),
						randomScalingFactor(),
						randomScalingFactor()
					],
				}]
			},
			options: {
				responsive: true,
				title: {
					display: true,
					text: 'Tiêu Đề'
				},
				tooltips: {
					mode: 'index',
					intersect: false,
				},
				hover: {
					mode: 'nearest',
					intersect: true
				},
				scales: {
					xAxes: [{
						display: true,
						scaleLabel: {
							display: true,
							labelString: 'Month'
						}
					}],
					yAxes: [{
						display: true,
						scaleLabel: {
							display: true,
							labelString: 'Value'
						}
					}]
				}
			}
		};

		window.onload = function() {
			var ctx = document.getElementById('canvas').getContext('2d');
			window.myLine = new Chart(ctx, config);
		};

		document.getElementById('randomizeData').addEventListener('click', function() {
			config.data.datasets.forEach(function(dataset) {
				dataset.data = dataset.data.map(function() {
					return randomScalingFactor();
				});

			});

			window.myLine.update();
		});

		var colorNames = Object.keys(window.chartColors);
		document.getElementById('addDataset').addEventListener('click', function() {
			var colorName = colorNames[config.data.datasets.length % colorNames.length];
			var newColor = window.chartColors[colorName];
			var newDataset = {
				label: 'Dataset ' + config.data.datasets.length,
				backgroundColor: newColor,
				borderColor: newColor,
				data: [],
				fill: false
			};

			for (var index = 0; index < config.data.labels.length; ++index) {
				newDataset.data.push(randomScalingFactor());
			}

			config.data.datasets.push(newDataset);
			window.myLine.update();
		});

		document.getElementById('addData').addEventListener('click', function() {
			if (config.data.datasets.length > 0) {
				var month = MONTHS[config.data.labels.length % MONTHS.length];
				config.data.labels.push(month);

				config.data.datasets.forEach(function(dataset) {
					dataset.data.push(randomScalingFactor());
				});

				window.myLine.update();
			}
		});

		document.getElementById('removeDataset').addEventListener('click', function() {
			config.data.datasets.splice(0, 1);
			window.myLine.update();
		});

		document.getElementById('removeData').addEventListener('click', function() {
			config.data.labels.splice(-1, 1); // remove the label first

			config.data.datasets.forEach(function(dataset) {
				dataset.data.pop();
			});

			window.myLine.update();
		});

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