Question

我想以图表的形式传输实时数据。我是Java语言的新手，所以我想先尝试一下此页面上的示例。 https://nagix.github.io/chartjs-plugin-streaming/samples/line-horizontal.html

代码为：

var chartColors = {
	red: 'rgb(255, 99, 132)',
	orange: 'rgb(255, 159, 64)',
	yellow: 'rgb(255, 205, 86)',
	green: 'rgb(75, 192, 192)',
	blue: 'rgb(54, 162, 235)',
	purple: 'rgb(153, 102, 255)',
	grey: 'rgb(201, 203, 207)'
};

function randomScalingFactor() {
	return (Math.random() > 0.5 ? 1.0 : -1.0) * Math.round(Math.random() * 100);
}

function onRefresh(chart) {
	chart.config.data.datasets.forEach(function(dataset) {
		dataset.data.push({
			x: Date.now(),
			y: randomScalingFactor()
		});
	});
}

var color = Chart.helpers.color;
var config = {
	type: 'line',
	data: {
		datasets: [{
			label: 'Dataset 1 (linear interpolation)',
			backgroundColor: color(chartColors.red).alpha(0.5).rgbString(),
			borderColor: chartColors.red,
			fill: false,
			lineTension: 0,
			borderDash: [8, 4],
			data: []
		}, {
			label: 'Dataset 2 (cubic interpolation)',
			backgroundColor: color(chartColors.blue).alpha(0.5).rgbString(),
			borderColor: chartColors.blue,
			fill: false,
			cubicInterpolationMode: 'monotone',
			data: []
		}]
	},
	options: {
		title: {
			display: true,
			text: 'Line chart (hotizontal scroll) sample'
		},
		scales: {
			xAxes: [{
				type: 'realtime'
			}],
			yAxes: [{
				scaleLabel: {
					display: true,
					labelString: 'value'
				}
			}]
		},
		tooltips: {
			mode: 'nearest',
			intersect: false
		},
		hover: {
			mode: 'nearest',
			intersect: false
		},
		plugins: {
			streaming: {
				duration: 20000,
				refresh: 1000,
				delay: 2000,
				onRefresh: onRefresh
			}
		}
	}
};

window.onload = function() {
	var ctx = document.getElementById('myChart').getContext('2d');
	window.myChart = new Chart(ctx, config);
};

document.getElementById('randomizeData').addEventListener('click', function() {
	config.data.datasets.forEach(function(dataset) {
		dataset.data.forEach(function(dataObj) {
			dataObj.y = randomScalingFactor();
		});
	});
	window.myChart.update();
});

var colorNames = Object.keys(chartColors);
document.getElementById('addDataset').addEventListener('click', function() {
	var colorName = colorNames[config.data.datasets.length % colorNames.length];
	var newColor = chartColors[colorName];
	var newDataset = {
		label: 'Dataset ' + (config.data.datasets.length + 1),
		backgroundColor: color(newColor).alpha(0.5).rgbString(),
		borderColor: newColor,
		fill: false,
		lineTension: 0,
		data: []
	};

	config.data.datasets.push(newDataset);
	window.myChart.update();
});

document.getElementById('removeDataset').addEventListener('click', function() {
	config.data.datasets.pop();
	window.myChart.update();
});

document.getElementById('addData').addEventListener('click', function() {
	onRefresh(window.myChart);
	window.myChart.update();
});

<head>
	<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.22.2/moment.min.js"></script>
	<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.7.2/Chart.min.js"></script>
	<script src="https://github.com/nagix/chartjs-plugin-streaming/releases/download/v1.5.0/chartjs-plugin-streaming.min.js"></script>
</head>
<body>
	<div>
		<canvas id="myChart"></canvas>
	</div>
	<p>
		<button id="randomizeData">Randomize Data</button>
		<button id="addDataset">Add Dataset</button>
		<button id="removeDataset">Remove Dataset</button>
		<button id="addData">Add Data</button>
	</p>
</body>

当我将其复制并粘贴到jsfiddle中时，第一个代码段进入Javascript部分，第二个代码段进入HTML部分。但是，什么都没有发生？有人可以解释为什么/帮助我对其进行编辑以使其起作用吗？

注意：以上代码不是我自己的，它属于this guy

Answer 1

在JSFiddle中，加载类型默认情况下设置为“加载时”，因此您无法处理加载事件。可以将加载类型设置为“ No wrap-bottom of”（在Javascript部分的弹出菜单中）。

使用chart.js，javascript，html

1 个答案: