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7d3a1b874c
* add sample plugin for doughnut empty state * Add commented out sample, order sub cats alphabetically
78 lines
1.5 KiB
Markdown
78 lines
1.5 KiB
Markdown
# Doughnut Empty State
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```js chart-editor
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// <block:data:2>
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const data = {
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labels: [],
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datasets: [
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{
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label: 'Dataset 1',
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data: []
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}
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]
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};
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// </block:data>
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// <block:plugin:1>
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const plugin = {
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id: 'emptyDoughnut',
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afterDraw(chart, args, options) {
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const {datasets} = chart.data;
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const {color, width, radiusDecrease} = options;
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let hasData = false;
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for (let i = 0; i < datasets.length; i += 1) {
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const dataset = datasets[i];
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hasData |= dataset.data.length > 0;
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}
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if (!hasData) {
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const {chartArea: {left, top, right, bottom}, ctx} = chart;
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const centerX = (left + right) / 2;
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const centerY = (top + bottom) / 2;
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const r = Math.min(right - left, bottom - top) / 2;
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ctx.beginPath();
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ctx.lineWidth = width || 2;
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ctx.strokeStyle = color || 'rgba(255, 128, 0, 0.5)';
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ctx.arc(centerX, centerY, (r - radiusDecrease || 0), 0, 2 * Math.PI);
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ctx.stroke();
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}
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}
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};
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// </block:plugin>
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// <block:config:0>
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const config = {
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type: 'doughnut',
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data: data,
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options: {
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plugins: {
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emptyDoughnut: {
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color: 'rgba(255, 128, 0, 0.5)',
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width: 2,
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radiusDecrease: 20
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}
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}
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},
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plugins: [plugin]
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};
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// </block:config>
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const actions = [
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{
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name: 'Randomize',
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handler(chart) {
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chart.data.datasets.forEach(dataset => {
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dataset.data = Utils.points(NUMBER_CFG);
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});
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chart.update();
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}
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},
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];
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module.exports = {
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actions,
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config,
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};
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