PDA

View Full Version : Sencha Touch - Performance and Responsiveness



nzkatre
4 Aug 2012, 12:32 AM
I have a few fundamental questions about the performance of SenchaTouch based apps. Please refer to this article by LinkedLN team on how they improved the performance of their HTML5 app by hand coding DOM Manipulations :-
http://engineering.linkedin.com/linkedin-ipad-5-techniques-smooth-infinite-scrolling-html5
In the context of this article I see two issues with Sencha Touch :-

Sencha Touch builds its UI by converting javascript objects into Dom Nodes and adding them into the Dom Tree. Chrome Tools will show that it ends up adding a relatively high number of DIVs and other DOM elements to the Dom tree. Wouldnt this have a detrimental effect on the performance.
Most of the Dom nodes in the Sencha UI are generated by Sencha API code and not from markup. If we write code to directly manipulate these Dom elements, can we be sure that it will not produce any side effects ?

kostysh
4 Aug 2012, 8:40 AM
Sencha Touch allows you to manipulate of app DOM tree. You can implement own strategy of how to work with tons of your application's DOM elements. You can remove and put to cache unused DOM elements and restore them if it necessary.

Of course if you manipulate DOM nodes directly when you can expect any side effects. You should investigate how your manipulation affect on Sencha framework.