Chart.js/samples/zoom.html
2016-04-21 07:48:47 -04:00

233 lines
8.0 KiB
HTML

<!doctype html>
<html>
<head>
<title>Scatter Chart</title>
<script src="../dist/Chart.bundle.js"></script>
<script src="http://cdnjs.cloudflare.com/ajax/libs/jquery/2.1.3/jquery.min.js"></script>
<style>
canvas {
-moz-user-select: none;
-webkit-user-select: none;
-ms-user-select: none;
}
</style>
</head>
<body>
<div style="width:75%">
<div>
<canvas id="canvas"></canvas>
</div>
</div>
<script src="http://hammerjs.github.io/dist/hammer.min.js"></script>
<script type="text/javascript">
var helpers = Chart.helpers;
function canZoomDirection(mode, dir) {
if (mode === undefined) {
return true;
} else if (typeof mode === 'string') {
return mode.indexOf(dir) !== -1;
}
return false;
}
function zoomScaleIn(scale, zoom, center) {
if (typeof scale.min === 'number' && typeof scale.max === 'number') {
var newDiff = (scale.max - scale.min) * (zoom - 1);
scale.options.ticks.min = scale.min + (newDiff / 2);
scale.options.ticks.max = scale.max - (newDiff / 2);
} else {
// Category scale
var indexDiff = scale.maxIndex - scale.minIndex;
}
}
function doZoom(chartInstance, zoom, center) {
var ca = chartInstance.chartArea;
if (!center) {
center = {
x: (ca.left + ca.right) / 2,
y: (ca.top + ca.bottom) / 2,
}
}
if (chartInstance.options.zoom && chartInstance.options.zoom.enabled) {
// Do the zoom here
helpers.each(chartInstance.scales, function(scale, id) {
if (scale.isHorizontal() && canZoomDirection(chartInstance.options.zoom.mode, 'x')) {
zoomScaleIn(scale, zoom, center);
} else if (canZoomDirection(chartInstance.options.zoom.mode, 'y')) {
// Do Y zoom
zoomScaleIn(scale, zoom, center);
}
});
chartInstance.update();
}
}
// Chartjs Zoom Plugin
var ZoomPlugin = Chart.PluginBase.extend({
beforeInit: function(chartInstance) {
var node = chartInstance.chart.ctx.canvas;
var options = chartInstance.options;
var wheelHandler = function(e) {
if (e.wheelDelta > 0) {
doZoom(chartInstance, 1.1);
} else {
doZoom(chartInstance, 0.909);
}
};
chartInstance._wheelHandler = wheelHandler;
node.addEventListener('mousewheel', wheelHandler);
var mc = new window.Hammer.Manager(node);
mc.add(new Hammer.Pinch());
var handlePinch = function handlePinch(e) {
var diff = 1 / (currentPinchScaling) * e.scale;
doZoom(chartInstance, diff, e.center);
// Keep track of overall scale
currentPinchScaling = e.scale;
};
// Hammer reports the total scaling. We need the incremental amount
var currentPinchScaling;
mc.on('pinchstart', function(e) {
currentPinchScaling = 1; // reset tracker
});
mc.on('pinch', handlePinch);
mc.on('pinchend', function(e) {
handlePinch(e);
currentPinchScaling = null; // reset
});
},
destroy: function(chartInstance) {
var node = chartInstance.chart.ctx.canvas;
// Remove wheel handler
node.removeEventListener('mousewheel', chartInstance._wheelHandler);
}
});
Chart.pluginService.register(new ZoomPlugin());
</script>
<script>
var randomScalingFactor = function() {
return (Math.random() > 0.5 ? 1.0 : -1.0) * Math.round(Math.random() * 100);
};
var randomColor = function(opacity) {
return 'rgba(' + Math.round(Math.random() * 255) + ',' + Math.round(Math.random() * 255) + ',' + Math.round(Math.random() * 255) + ',' + (opacity || '.3') + ')';
};
var scatterChartData = {
datasets: [{
label: "My First dataset",
data: [{
x: randomScalingFactor(),
y: randomScalingFactor(),
}, {
x: randomScalingFactor(),
y: randomScalingFactor(),
}, {
x: randomScalingFactor(),
y: randomScalingFactor(),
}, {
x: randomScalingFactor(),
y: randomScalingFactor(),
}, {
x: randomScalingFactor(),
y: randomScalingFactor(),
}, {
x: randomScalingFactor(),
y: randomScalingFactor(),
}, {
x: randomScalingFactor(),
y: randomScalingFactor(),
}]
}, {
label: "My Second dataset",
data: [{
x: randomScalingFactor(),
y: randomScalingFactor(),
}, {
x: randomScalingFactor(),
y: randomScalingFactor(),
}, {
x: randomScalingFactor(),
y: randomScalingFactor(),
}, {
x: randomScalingFactor(),
y: randomScalingFactor(),
}, {
x: randomScalingFactor(),
y: randomScalingFactor(),
}, {
x: randomScalingFactor(),
y: randomScalingFactor(),
}, {
x: randomScalingFactor(),
y: randomScalingFactor(),
}]
}]
};
$.each(scatterChartData.datasets, function(i, dataset) {
dataset.borderColor = randomColor(0.4);
dataset.backgroundColor = randomColor(0.1);
dataset.pointBorderColor = randomColor(0.7);
dataset.pointBackgroundColor = randomColor(0.5);
dataset.pointBorderWidth = 1;
});
window.onload = function() {
var ctx = document.getElementById("canvas").getContext("2d");
window.myScatter = Chart.Scatter(ctx, {
data: scatterChartData,
options: {
title: {
display: true,
text: 'Chart.js Scatter Chart'
},
scales: {
xAxes: [{
gridLines: {
zeroLineColor: "rgba(0,255,0,1)"
},
scaleLabel: {
display: true,
labelString: 'x axis'
},
ticks: {
maxRotation: 0
}
}],
yAxes: [{
gridLines: {
zeroLineColor: "rgba(0,255,0,1)"
},
scaleLabel: {
display: true,
labelString: 'y axis'
}
}]
},
zoom: {
enabled: true,
mode: 'x'
}
}
});
};
</script>
</body>
</html>