System services not available to Activities before onCreate() [KOTLIN]-CodePudding

I have hideKeyboard(view: View) method in util class. In my activity I want to call that method. I created object in activity utils = Utils() and then utils.HideKeyboard(binding.authConstraint) but when Im trying to click on constraintLayout it is throwing error "System services not available to Activities before onCreate()" what am I doing wrong ?

my Util Class

open class  Utils():Activity(){

     fun hideKeyboard(view: View) {
        val inputMethodManager =
            getSystemService(Activity.INPUT_METHOD_SERVICE) as InputMethodManager
        inputMethodManager.hideSoftInputFromWindow(view.windowToken, 0)
    }

my activity

class AuthActivity : ActivityWithDisposableList() {
    private lateinit var binding: ActivityAuthBinding
    private lateinit var authViewModel: AuthViewModel
    val utils = Utils()


    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        binding = DataBindingUtil.setContentView(this, R.layout.activity_auth)

        authViewModel = ViewModelProviders.of(this).get(AuthViewModel::class.java)

        binding.authViewModel = authViewModel
        binding.lifecycleOwner = this



        authViewModel.isKeyboardClosed.observe(this, Observer { isTrue ->
            if (isTrue) {
                utils.hideKeyboard(binding.authConstraint,this)
                binding.usernameInputEditText.clearFocus()
                binding.passwordInputEditText.clearFocus()
            }
        })

    }


}

CodePudding user response：

Do not create an instance of an Activity subclass yourself. And do not make some arbitrary class extend Activity, just because you need a Context. Get the Context from a parameter to a constructor or function.

With that in mind, replace your Utils with:

class Utils {
    fun hideKeyboard(view: View) {
        val inputMethodManager =
            view.context.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
        inputMethodManager.hideSoftInputFromWindow(view.windowToken, 0)
    }
}

Here, you are getting the Context from the View that you are supplying.

Note that you could also go with object Utils or have hideKeyboard() be an extension function on View, if you liked.