假设我有一个直方图脚本,构建960 500 svg图形。我如何使这个响应,以便调整图形的宽度和高度是动态的?
<script>
var n = 10000, // number of trials
m = 10, // number of random variables
data = [];
// Generate an Irwin-Hall distribution.
for (var i = 0; i < n; i++) {
for (var s = 0, j = 0; j < m; j++) {
s += Math.random();
}
data.push(s);
}
var histogram = d3.layout.histogram()
(data);
var width = 960,
height = 500;
var x = d3.scale.ordinal()
.domain(histogram.map(function(d) { return d.x; }))
.rangeRoundBands([0, width]);
var y = d3.scale.linear()
.domain([0, d3.max(histogram.map(function(d) { return d.y; }))])
.range([0, height]);
var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height);
svg.selectAll("rect")
.data(histogram)
.enter().append("rect")
.attr("width", x.rangeBand())
.attr("x", function(d) { return x(d.x); })
.attr("y", function(d) { return height - y(d.y); })
.attr("height", function(d) { return y(d.y); });
svg.append("line")
.attr("x1", 0)
.attr("x2", width)
.attr("y1", height)
.attr("y2", height);
</script>
完整的直方图示例要点如下:
https://gist.github.com/993912
寻找“响应式SVG”,使SVG响应式非常简单,您不必再担心大小问题。
以下是我的做法:
d3.select("div#chartId")
.append("div")
.classed("svg-container", true) //container class to make it responsive
.append("svg")
//responsive SVG needs these 2 attributes and no width and height attr
.attr("preserveAspectRatio", "xMinYMin meet")
.attr("viewBox", "0 0 600 400")
//class to make it responsive
.classed("svg-content-responsive", true);
CSS代码:
.svg-container {
display: inline-block;
position: relative;
width: 100%;
padding-bottom: 100%; /* aspect ratio */
vertical-align: top;
overflow: hidden;
}
.svg-content-responsive {
display: inline-block;
position: absolute;
top: 10px;
left: 0;
}
更多信息/教程:
http://demosthenes.info/blog/744/Make-SVG-Responsive
http://soqr.fr/testsvg/embed-svg-liquid-layout-responsive-web-design.php
以防人们还在问这个问题——以下是对我有用的方法:
Enclose the iframe in a div and use css to add a padding of, say, 40% to that div (the percentage depending on the aspect ratio you want). Then set both width and height of the iframe itself to 100%.
In the html doc containing the chart to be loaded in the iframe, set width to the width of the div that the svg is appended to (or to the width of the body) and set height to width * aspect ratio.
Write a function that reloads the iframe content upon window resize, so as to adapt the size of the chart when people rotate their phone.
在我的网站上有一个例子:
http://dirkmjk.nl/en/2016/05/embedding-d3js-charts-responsive-website
2016年12月30日更新
我上面描述的方法有一些缺点,特别是它没有考虑任何不在d3创建的svg中的标题和说明文字的高度。后来我想到了一个我认为更好的方法:
将D3图表的宽度设置为它所附的div的宽度,并使用纵横比来相应地设置它的高度;
使用HTML5的postMessage将嵌入页面的高度和url发送到父页面;
在父页面上,使用url识别相应的iframe(如果页面上有多个iframe,则很有用),并将其高度更新为嵌入页面的高度。
例子在我的网站上:http://dirkmjk.nl/en/2016/12/embedding-d3js-charts-responsive-website-better-solution
我写了一个小要点来解决这个问题。
一般的解决模式是这样的:
Breakout the script into computation and drawing functions.
Ensure the drawing function draws dynamically and is driven of
visualisation width and height variables (The best way to do this is
to use the d3.scale api)
Bind/chain the drawing to a reference
element in the markup. (I used jquery for this, so imported it).
Remember to remove it if it's already drawn. Get the dimensions from
the referenced element using jquery.
Bind/chain the draw function to
the window resize function. Introduce a debounce (timeout) to this
chain to ensure we only redraw after a timeout.
为了提高速度,我还添加了简化的d3.js脚本。
要点在这里:https://gist.github.com/2414111
Jquery参考回码:
$(reference).empty()
var width = $(reference).width();
防反跳代码:
var debounce = function(fn, timeout)
{
var timeoutID = -1;
return function() {
if (timeoutID > -1) {
window.clearTimeout(timeoutID);
}
timeoutID = window.setTimeout(fn, timeout);
}
};
var debounced_draw = debounce(function() {
draw_histogram(div_name, pos_data, neg_data);
}, 125);
$(window).resize(debounced_draw);
享受吧!
还有另一种不需要重绘图形的方法,它涉及到修改<svg>元素上的viewBox和preserveAspectRatio属性:
<svg id="chart" viewBox="0 0 960 500"
preserveAspectRatio="xMidYMid meet">
</svg>
15年11月24日更新:大多数现代浏览器可以从viewBox推断SVG元素的纵横比,所以你可能不需要保持图表的大小。如果你需要支持旧的浏览器,你可以在窗口调整大小时调整元素的大小,就像这样:
var aspect = width / height,
chart = d3.select('#chart');
d3.select(window)
.on("resize", function() {
var targetWidth = chart.node().getBoundingClientRect().width;
chart.attr("width", targetWidth);
chart.attr("height", targetWidth / aspect);
});
svg内容将自动缩放。你可以在这里看到一个工作示例(进行了一些修改):调整窗口或右下角窗格的大小,看看它是如何反应的。