Ion-toggle doesn't call ng-change function

Hello everyone, I am switching ion-toggle as shown is calling vatt() function, when I click the toggle’s switch button.But when I change it using another button, it is switching toggle’s side, but it does not call validate() function.How can I solve this problem?

  <ion-toggle ng-model="p.checked"
                        class="item item-text-wrap">

                My Toggle

        <button class="button button-positive" ng-click="check()">Tikla</button>

my controller script has this codes.

  $scope.p=  {id: 1, text: 'USA', checked: false, icon: null} ;
 $scope.check = function () {
  $scope.p.checked = false;
 $scope.vatt = function () {

I used ng-model and ng-checked.

in a controller:
$scope.toggleBoolean = false;

in a template:
<ion-toggle ng-model="toggleBoolean" ng-checked="toggleBoolean"></ion-toggle>