Very slow in IE 11

[rakiUK]

Currently I am facing an issue with this tree widget, that is very slow rendering in IE11, where as in chrome it works as expected. There are around 2200 items(_including nested) in the tree . I have tried to put limitTo:10 for ng-repeat but still the problem exists.

Any pointers to improve the performance in IE (atleast similar to chrome) will be really helpful.

Thanks very much.

[igorlino]

First of all, its a nice looking widget. Thanks @AlexSuleap

Taking a look at the code of the library and some example in my own code, this are my findings: 1) The root problem in this widget is that is generates way too many angular handlers. Tree data structure tend to be larger biggish. (that's why we often need them) A simple list of some hundreds of items will easily take 2000 angular handlers.

(Recomendation for a webapp based on angular, in total, not to exceed 3000 handlers, so its of course dificult to have a widget that consumes 66% already by itself)

2) I think, in general with widgets, relying too much on angular to generate the widget html is a very expensive thing to do, and does not scale.

I think one has to rewrite several parts of the widget to improve the performance. Perhaps the following will help:

• Use ng-if for collapsed nodes, so that they don't consume handlers.
• Use a single ng-click for whole tree, and generate uuid attribute for all nodes (with single-bindings) so that its easy get back the node in that simplified ng-click.
• Remove usage of ng-classes as much as possible. Replace it with direct DOM manipulation when possible.
• Optimize ng-repeats by using 'track by' with the node UUID, otherwise they need to be generated.
• Difficult: think of a way to remove ng-repeats.
• Add option to disable animations.

I think this would reduce by 80-95% the angular handlers, and definitively the rendering will much faster.