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javascript - How to use ng-if with ng-repeat?

I have a simple nav object setup that lists the nav items (and whether they should appear in the primary nav or not). It seems though when I try to mix ng-if with ng-repeat, things fall apart, but when I mix ng-show with ng-repeat it works fine (but I end up with a bunch of hidden elements that I don't want appended to the DOM).

   <section class="nav">
        <a  ng-repeat="(key, item) in route.routes"
            ng-href="{{key}}"
            ng-show="item.nav"
        >
                {{item.label}}
        </a>
    </section>

But the following doesn't work (note the ng-show is now ng-if):

    <section class="nav">
    <a  ng-repeat="(key, item) in route.routes"
        ng-href="{{key}}"
        ng-if="item.nav"
    >
            {{item.label}}
    </a>
</section>

The routes object looks like

routes: {
    '/home': { label: 'Home', nav: true },
    '/contact': { label: 'Contact', nav: false},
   // etc
}

I receive the following error when trying to use ng-if:

Error: Multiple directives [ngIf, ngRepeat] asking for transclusion on:

I guess it's trying to tell me that I can't state it's declaration for existing twice. I could use ng-if on an inner element, but I think I would still end up with a bunch of empty outer a tags.

See Question&Answers more detail:os

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1 Reply

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by (71.8m points)

There's probably a better solution, but after reading the replies above, you can try making your own custom filter:

angular.module('yourModule').filter('filterNavItems', function() {
  return function(input) {
    var inputArray = [];

    for(var item in input) {
      inputArray.push(input[item]);
    }

    return inputArray.filter(function(v) { return v.nav; });
  };
});

Then to use it:

<section class="nav">
    <a  ng-repeat="(key, item) in routes | filterNavItems"
        ng-href="{{key}}">
            {{item.label}}
    </a>
</section>

Here's the Plunker: http://plnkr.co/edit/srMbxK?p=preview


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