$ionicPopup: can't bind data from the popup template

I have a popup with list of options “radio” i can’t bind the value of the option to the controller where am building item object.
Am getting in the console Tapped! undefined
my controller code

.controller('newItemCtrl', function($scope, $http, $ionicPopup) {
    
$scope.item = {
        title: $scope.title,
        price: $scope.price,
        desc: $scope.description,
        picture: $scope.picture
    }; 
  $scope.list = [{
        id: 1,
        title: 'Women clothes'
    }, {
        id: 2,
        title: 'Men clothes'
    }, {
        id: 3,
        title: 'Restaurant & Lounge'
    }, {
        id: 4,
        title: 'Accessories'
    }, {
        id: 5,
        title: 'Digital gadgets'
    }, ];
    $scope.addFromList = function() {
        $scope.item = {}
        var myPopup = $ionicPopup.show({
            templateUrl: 'templates/cat-opitions.html',
            title: 'Select',
            scope: $scope,
            buttons: [{
                text: 'Ok',
                type: 'button sharb-border white-font blue-bg-alt border-blue-alt',
                onTap: function() {
                    return $scope.item.category;
                }
            }]
        });
        myPopup.then(function(res) {
            console.log('Tapped!', res);
        });
    };
})

The popup template:

<label class="item item-radio" ng-repeat="item in list">
    <input type="radio" name="group" ng-model="item.category" ng-value="item.title">
    <div class="item-content">{{ item.title }}</div>
    <i class="radio-icon ion-checkmark"></i>
</label>