[![enter image description here](https://i.stack.imgur.com/9WZE7.png)](https://i.stack.imgur.com/9WZE7.png)How to call the function when click on button. I created the button and print (hello on console). It will print but when I define the function for simple addition of two number then it gives error.

I used the following code:

```
var FormCustomControllerMixin = {
   init: function (parent, model, renderer, params) {
       this.importEnabled = params.importEnabled;
   },

   _getLocation : function(){
       var a=10;
       var b=20;
       var c= a+b;
       console.log(c);
   },

   _bindImport: function () {
       if (!this.$buttons) {
           return;
       }
       var self = this;
       this.$buttons.on('click', '.o_button_custom_form', function () {
           console.log('Hello');
           a=self._getLocation();
         console.log(a);
       });
   }
};

```

Hello is print but addition is not perform.