Zoom Google Line chart | 易学教程

问题

I am trying to create a line chart with the Google Visualization API. I want to enable zooming. Documents say that the 'explorer' option is useful. But when I try to use the 'explorer' option, the chart is shown but zoom does not work.

This is my code:

function drawVisualization(dataValues) {
var data = new window.google.visualization.DataTable();
data.addColumn('date', 'Date');
data.addColumn('number', 'Count');

for (var i = 0; i < dataValues.length; i++) {
    data.addRow([new Date(dataValues[i].Year, dataValues[i].Month-1, dataValues[i].Day), dataValues[i].Count]);
}

var formatter_short = new google.visualization.DateFormat({ formatType: 'short' });
formatter_short.format(data, 0);
var options = {
    title: "Time statistics",
    explorer: { maxZoomOut: 8 }
};
var chart = new google.visualization.LineChart(document.getElementById('date'));
chart.draw(data, options);
}

How can I resolve this problem and make a line chart zoomable?

回答1:

Here is How I got the zoom with the dragToZoom explorer function

explorer: { 
        actions: ['dragToZoom', 'rightClickToReset'],
        axis: 'horizontal',
        keepInBounds: true,
        maxZoomIn: 4.0
}

the fiddle is here https://jsfiddle.net/4w626v2s/2/

also by just allowing it to zoom by scrolling

explorer: {
        axis: 'horizontal',
        keepInBounds: true,
        maxZoomIn: 4.0
}

the fiddle for scroll to zoom is here https://jsfiddle.net/5h7jxqq8/2/

回答2:

This seems to be working now with LineChart AND ColumnChart (even though this one is not documented).

var options = {
    explorer: {
        maxZoomOut:2,
        keepInBounds: true
    }
};

http://jsfiddle.net/duJA8/

回答3:

Try this:

<html>
	<head>
		<script type="text/javascript" src="https://www.gstatic.com/charts/loader.js"></script>
		<script type="text/javascript">
			google.charts.load('current', {
				callback: function () {
					drawChart();
					window.addEventListener('resize', drawChart, false);
				},
				packages:['corechart']
			});

			function drawChart() {
				var data = google.visualization.arrayToDataTable([
					['Year', 'Sales', 'Expenses', 'Profit'],
					['2014', 1000, 400, 200],
					['2015', 1170, 460, 250],
					['2016', 660, 1120, 300],
					['2017', 1030, 540, 350]
				]);

				var options = {
					animation:{
						duration: 1000,
						easing: 'linear',
						startup: true
					},
					height: 600,
					width: window.innerWidth,
					theme: 'material',
					title: 'Company Performance'
				};

				var chart = new google.visualization.ColumnChart(document.getElementById('columnchart_material'));
				chart.draw(data, options);
			}
		</script>
	</head>
	<body>
		<div id="columnchart_material" style="height: 500px; "></div>
	</body>
</html>

If you want to set Width and Height according to the Screen. So, you can achieve this by using "innerWidth" and "innerHeight" as shown below:

<html>
	<head>
		<script type="text/javascript" src="https://www.gstatic.com/charts/loader.js"></script>
		<script type="text/javascript">
			google.charts.load('current', {
				callback: function () {
					drawChart();
					window.addEventListener('resize', drawChart, false);
				},
				packages:['corechart']
			});

			function drawChart() {
				var data = google.visualization.arrayToDataTable([
					['Year', 'Sales', 'Expenses', 'Profit'],
					['2014', 1000, 400, 200],
					['2015', 1170, 460, 250],
					['2016', 660, 1120, 300],
					['2017', 1030, 540, 350]
				]);

				var options = {
					animation:{
						duration: 1000,
						easing: 'linear',
						startup: true
					},
					height: window.innerHeight,
					width: window.innerWidth,
					theme: 'material',
					title: 'Company Performance'
				};

				var chart = new google.visualization.ColumnChart(document.getElementById('columnchart_material'));
				chart.draw(data, options);
			}
		</script>
	</head>
	<body>
		<div id="columnchart_material"></div>
	</body>
</html>

I hope it helps you to solve the problem.

来源：https://stackoverflow.com/questions/20764157/zoom-google-line-chart

标签

javascript

charts

google-visualization

linechart