how to call a controller in ionic?

In my ionic blank app, i have two html file index.html and category.html. i write the controller for index.html in app.js like

.controller('AppCtrl',function($scope){
  $scope.menu = function() {
    console.log('yesytest');
    window.location = "category.html";
  };

})

this is working fine and after reaching the category page i create another controller in app.js

    controller('categoryCtrl',function($scope){
        console.log('ffffffffff');
    $scope.beauty = function() {
        console.log('yesytest');
        window.location = "categorydetails.html";

    };

});

i add a ng-click function on a button inside category.html but when i click on that button it is not calling the controller?

You can define your controller either on : - defining it on your ui router state

    .state('camera',{
            url:"/camera",
            cache: false,
            controller:"CameraCtrl",
            templateUrl:'app/views/loading/index.html'
    })

Or by defining it into tour template category.html

<div ng-controller="categoryCtrl"> .... </div>

This is standard AngularJS feature, nothing special with ionic

If you use this :

.state('category',{
url:"/category",
controller:"categoryCtrl",
templateUrl:'templates/category.html'
})

You can use ui-sref="stateId" to do redirection Example:

  <a ui-sref="category"></a>