Thank you for reporting this bug. We will make it our priority to review this report.
[OPEN-EXTJSIV-183] Slow container creation and browser crashing.
I have been working on an example for testing performance of object creation and eventing. I have a script that seems to work well, but it's horribly slow and actually kills something in the browser at some point.
I have attached a zip that contains my JS files (as well as ext) and the html loading page.
This essentially creates 150 containers with a text box & button. Clicking on a button causes a label change in the next box and clicks on that button.
This should all load fairly quickly, but takes so long to create the boxes that the browser tags it as unresponsive. You can let it continue, but it only ever gets 140 created. If you have the dev tools (in IE) open, it will crash the browser at 140 items.
We still have much optimization to do, particularly with framework initialization and layouts. This will be quite helpful, thank you for the sample.
The optimization was only one aspect here. The other was that it breaks and stops in IE after only 140 panels. There seems to be no indication of why it failed either.
It seems to show up fine in chrome (although it is slow there too).
Thanks for the quick reply!
I did find a short-term workaround for this (as the logic is, it works on 3.3 with namespace changes). In the viewport config block, adding suspendLayout: true and then setting to false at the end and forcing a manual layout allows this to work. After doing this, all 150 blocks show up and the time consumed is much more realistic.
I will have to check through how you are adding items to the container. This may be a case where you want to control it manually like this. Which is what suspendLayout is for.