I have an ng-repeat set up like so:
ng-repeat="article in main[main.mode].primary | orderBy: main[main.mode].primary.filter.order
track by article.url"
main[main.mode].primary is an array and ….filter.order is a string.
According to this blog post
Behind the scenes ngRepeat adds a $$hashKey property to each task to keep track of it. If you replace the original tasks with new tasks objects from the server, even if those are in fact totally identical to your original tasks, they won’t have the $$hashKey property and so ngRepeat won’t know they represent the same elements.
Regenerating the list is a very common task and the app is hanging for over a second, hence my interest in track by. According to the many questions and docs I've looked at, I've used the correct syntax to both order and track an array. From the docs:
item in items | filter:searchText track by item.id is a pattern that might be used to apply a filter to items in conjunction with a tracking expression.
Why isn't track by being implemented? I'm running angular 1.3.11.
Edit It doesn't even work if I remove the orderBy argument
ng-repeat="article in main[main.mode].primary track by article.url"
according to the Angular Documentation orderBy only works on arrays so if you are iterating over an object you are not going to be able to use it unless you convert your object into an array
https://docs.angularjs.org/api/ng/filter/orderBy
there are other ways you can handle this either implementing your own filter or just by transforming your object into an array of objects with key value properties. something like
var narr=[]
angular.forEach(object,function(k,v){
narr.push({key:v,value:v})
})
and now narr is an array ready to be sorted by either key or value using orderBy