Referring to outer scope variables in orderBy inside ng-repeat

Question

I'd like to have an ng-repeat that's sorted by a value in some external lookup table.

For example, suppose I have a list of items with an itemType for each item. I have a separate itemTypePriorities lookup table in the scope, such that itemTypePriorities[someItemType] gives the priority for a given item type. Now, I'd like to display items in order of their priorities. I am trying the following:

<div ng-repeat="item in items | orderBy:'itemTypePriorities[item.itemType]'>

But it doesn't seem to work - my guess is that it's interpreting the orderBy expression in the context of item, i.e. it's trying to order by the nonsensical expression item.itemTypePriorities[item.itemType].

Is there a way to rewrite the ng-repeat to make it wok correctly, without having to modify the items or itemTypePriorities arrays in any way?

Answer 1

You can use of course the orderBy filter but I think you will need to create a custom function to orderit.

For example:

<div ng-repeat="item in items | orderBy:myFunction>

Where myFunction is declared somewhere in your controller as:

$scope.myFunction = function(el){
    //el is the current element under evaluation
}

And should return a value that will be compared with <, === and > with the other. In your case the function can be:

$scope.myFunction = function(el){
    return itemTypePriorities.indexOf(el);
}

And that should work