How to speed up Inline SVG changes - svg

Question

In my hybrid Android app I use inline SVG to display images that are large (of the order of 2Mb) and complex (several hundred SVG elements per image). When I need to change the image I do the following
var puzzle = document.createElementNS(SVGNS,'svg'),
kutu = document.getElementById('kutu');
puzzle.id = 'puzzle';
puzzle.setAttribute('preserveAspectRatio','none');
puzzle.setAttribute('width','100vw');
puzzle.setAttribute('height','85.5vh');
puzzle.setAttribute('xmlns',SVGNS);
puzzle.setAttribute('xmlns:xlink',XLINK);
puzzle.setAttribute('fill-rule','evenodd');
puzzle.setAttribute('clip-rule','evenodd');
puzzle.setAttribute('stroke-linejoin','round');
puzzle.setAttribute('stroke-miterlimit','1.414');
puzzle.setAttribute('viewBox','0 0 1600 770');
puzzle.innerHTML = SVG;
//SVG here is the SVG image content shorn off the outer <svg>..</svg>
if (0 < kutu.children.length) kutu.children[0].remove();
//remove old image, iff any
kutu.appendChild(puzzle);
//append the new image
While this is working the process of displaying the new image is slow. I suspect it is because of the innerHTML assignment above. Recreating through a sequence of createElementNS, puzzle.àppendChild would require me to first parse the incoming raw SVG content etc. Is that the way to go or would there be a faster way to display the content.
Once again for clarity - SVG here is the content of the new SVG image to be displayed shorn of its outer <svg>...</svg> wrrapper.

Answer 1

Just a side note it would probably be better to use setAttributeNS in place of setAttribute for consistency purpose since createElementNS is used, though it might not make a difference in speeding up the SVG image change.
In the case of a native app, a tool like the Android Profiler if using Android Studio 3.0 and higher can be used to analyze performance bottleneck. However since your app is a hybrid app, some sort of performance profiler that's applicable to the hybrid app (Whether it's Ionic or Cordova, etc.) can help to pinpoint where your performance bottleneck is.
Since your app is a hybrid, without knowing the resource capacity of your android app session, the guess is it seems to be a possible cause that it calls something like .setAttribute to set session-level attributes on the fly during the change of the image and the session resource might not be enough, and also the DOM has to perform .innerHTML and appendChild, which are dynamic operations. DOM manipulation is known to be slow.
Conversion of attributes of all the SVGs and store the result in some sort of storage or cache, and when needed, call it from the persistent storage or cache might be helpful.
Or consider using AngularJS to do the SVG change beforehand and preload the SVG images, refer to easily preload images in your Angular app. Here is another similar code to yours except it's using AngularJS to add SVG for starters.
Another simpler way, without changing your code, if you could minify the incoming SVGs beforehand, is to use SVG Optimizer or SVGO, a node.js open source project to compress your SVGs. Quoted from the SVGO link it says:
"SVG files, especially those exported from various editors, usually contain a lot of redundant and useless information. This can include editor metadata, comments, hidden elements, default or non-optimal values and other stuff that can be safely removed or converted without affecting the SVG rendering result." Although the performance gain might not be obvious going this route.