I have found all other solutions where data is created in ts file and then used as String interpolation in html. When a category is checked, notifications in this category should also be checked. In the app.component.ts file, we will define an object of items using which we will create a list. Click to the master checkbox and see the result. It means if we do not select any radio button or checkbox is not checked then form will not be valid. we will use ng-model and ng-checked for doing simple check uncheck toggle event. In angularjs ng-change event is supported by ,