javascriptsvgviewbox

Manipulate SVG viewbox with JavaScript (no libraries)

I'm trying to alter an SVG elements viewbox in JavaScript. Basically, I'm drawing a binary search tree, and when it gets too wide, I want to alter the viewbox to zoom out so that the tree fits in the window. I'm currently using:

if(SVGWidth>=1000){
  var a = document.getElementById('svgArea');
  a.setAttribute("viewbox","0 0 " + SVGWidth + " 300");
}

The HTML is:

<svg id="svgArea" xmlns="w3.org/2000/svg"; xmlns:xlink="w3.org/1999/xlink"; width="1000" height="300" viewBox="0 0 1000 300">

I've also tried using setAttributeNS('null',...) but that didn't seem to work either. One strange thing I've noticed is that when I alert(a) it gives [object SVGSVGElement] which seems strange. Any help is appreciated.

Solution

  • It would be good to see the context of the svg, but the following worked for me with a pure SVG document:

    shape = document.getElementsByTagName("svg")[0];
shape.setAttribute("viewBox", "-250 -250 500 750");

    Maybe it's because viewBox is case-sensitive?