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brizental/chart-no-labels.js

Created June 22, 2018 06:17
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chart-no-labels.js
<!doctype html>
<html>
<head>
<title>Doughnut Chart</title>
<script src="../../dist/Chart.bundle.js"></script>
<script src="../utils.js"></script>
<style>
canvas {
-moz-user-select: none;
-webkit-user-select: none;
-ms-user-select: none;
}
</style>
</head>
<body>
<div id="canvas-holder" style="width:40%">
<canvas id="chart-area"></canvas>
</div>
<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>
<button id="changeCircleSize">Semi/Full Circle</button>
<script>
var randomScalingFactor = function() {
return Math.round(Math.random() * 100);
};
var isArray = Array.isArray ? Array.isArray : function(value) {
return Object.prototype.toString.call(value) === '[object Array]';
};
var valueOrDefault = function(value, defaultValue) {
return typeof value === 'undefined' ? defaultValue : value;
};
var valueAtIndexOrDefault = function(value, index, defaultValue) {
return valueOrDefault(isArray(value) ? value[index] : value, defaultValue);
};
var config = {
type: 'doughnut',
data: {
datasets: [{
data: [
randomScalingFactor(),
randomScalingFactor(),
randomScalingFactor(),
randomScalingFactor(),
randomScalingFactor(),
],
backgroundColor: [
window.chartColors.red,
window.chartColors.orange,
window.chartColors.yellow,
window.chartColors.green,
window.chartColors.blue,
],
label: 'Dataset 1'
}],
labels: [
'Red',
'Orange',
'Yellow',
'Green',
'Blue'
]
},
options: {
responsive: true,
legend: {
position: 'top',
labels: {
generateLabels: (chart) => {
var data = chart.data;
if (data.labels.length && data.datasets.length) {
return data.labels.map(function(label, i) {
var meta = chart.getDatasetMeta(0);
var ds = data.datasets[0];
var arc = meta.data[i];
var custom = arc && arc.custom || {};
var arcOpts = chart.options.elements.arc;
var fill = custom.backgroundColor ? custom.backgroundColor : valueAtIndexOrDefault(ds.backgroundColor, i, arcOpts.backgroundColor);
var stroke = custom.borderColor ? custom.borderColor : valueAtIndexOrDefault(ds.borderColor, i, arcOpts.borderColor);
var bw = custom.borderWidth ? custom.borderWidth : valueAtIndexOrDefault(ds.borderWidth, i, arcOpts.borderWidth);
return {
text: "",
fillStyle: fill,
strokeStyle: stroke,
lineWidth: bw,
hidden: isNaN(ds.data[i]) || meta.data[i].hidden,
// Extra data used for toggling the correct item
index: i
};
});
}
return [];
}
}
},
title: {
display: true,
text: 'Chart.js Doughnut Chart'
},
animation: {
animateScale: true,
animateRotate: true
}
}
};
window.onload = function() {
var ctx = document.getElementById('chart-area').getContext('2d');
window.myDoughnut = 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.myDoughnut.update();
});
var colorNames = Object.keys(window.chartColors);
document.getElementById('addDataset').addEventListener('click', function() {
var newDataset = {
backgroundColor: [],
data: [],
label: 'New dataset ' + config.data.datasets.length,
};
for (var index = 0; index < config.data.labels.length; ++index) {
newDataset.data.push(randomScalingFactor());
var colorName = colorNames[index % colorNames.length];
var newColor = window.chartColors[colorName];
newDataset.backgroundColor.push(newColor);
}
config.data.datasets.push(newDataset);
window.myDoughnut.update();
});
document.getElementById('addData').addEventListener('click', function() {
if (config.data.datasets.length > 0) {
config.data.labels.push('data #' + config.data.labels.length);
var colorName = colorNames[config.data.datasets[0].data.length % colorNames.length];
var newColor = window.chartColors[colorName];
config.data.datasets.forEach(function(dataset) {
dataset.data.push(randomScalingFactor());
dataset.backgroundColor.push(newColor);
});
window.myDoughnut.update();
}
});
document.getElementById('removeDataset').addEventListener('click', function() {
config.data.datasets.splice(0, 1);
window.myDoughnut.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();
dataset.backgroundColor.pop();
});
window.myDoughnut.update();
});
document.getElementById('changeCircleSize').addEventListener('click', function() {
if (window.myDoughnut.options.circumference === Math.PI) {
window.myDoughnut.options.circumference = 2 * Math.PI;
window.myDoughnut.options.rotation = -Math.PI / 2;
} else {
window.myDoughnut.options.circumference = Math.PI;
window.myDoughnut.options.rotation = -Math.PI;
}
window.myDoughnut.update();
});
</script>
</body>
</html>
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