Angularjs filter on nested property

Question

I have an array of the following json object:

 { 
    fooBar:{ 
        Id: 2
        Foo:  { 
                Id: 4
                IsNew: false
              } 
         Bar: { 
                Id: 1
                IsNew: false
              }
           }
  }

and I want to filter on the fooBar.Foo.Id, so based on this answer I was expecting the following to work:

<div data-ng-repeat="fooBar in fooBars | filter:{Foo:{Id : 4}}:true">

But this does not return me anything.

I can do the following however to filter on fooBar.Id and that works fine:

<div data-ng-repeat="fooBar in fooBars | filter:{Id : 2}:true">

Should I be writing custom filters for this kind of one level down child property matching? Or is there anything obvious that I am doing wrong?

Answer 1

Based on this answer, I solved the problem by creating a custom filter:

app.filter('fooBarFilter', [function () {
 return function (foobars, fooId) {
     var result = {};

     angular.forEach(foobars, function (foobar, key) {
         if (foobar.foo.Id === fooId) {
             result[key] = foobar;
         }
     });
     return result;
 };
}]);

and used it to filter the collection in the HTML:

 <div data-ng-repeat="(key, fooBar) in fooBars | fooBarFilter : 4">