Spaghetti Screens

SpaghettiActivity.kt

class MainActivity : AppCompatActivity() {

    var username: String? = null
    var passwordValue: String? = null
    var passwordField: EditText? = null
    val listener = object : TextWatcher {
        override fun afterTextChanged(s: Editable?) {}
        override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {}
        override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {
            username = s.toString()
            onPasswordChanged()
        }
    }

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

        setContentView(R.layout.activity_main)

        val view = findViewById<TextView>(R.id.screen_header)
        view.setText("Login Screen")

        login_form_username.addTextChangedListener(object : TextWatcher {
            override fun afterTextChanged(s: Editable?) { onPasswordChanged() }
            override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {}
            override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) { username = s.toString() }
        })

        passwordField = findViewById<EditText>(R.id.login_form_password)

        passwordField!!.addTextChangedListener(listener)

        login_form_submit_button.setOnClickListener {
            if(BuildConfig.DEBUG) {
                DebugLoginService().login() {
                    startActivity(Intent(this, HomeActivity::class.java))
                }
            }
            else {
                ProductionLoginService(LoginApi()).login(username!!, passwordValue!!) {
                    startActivity(Intent(this, HomeActivity::class.java))
                }
            }
        }
    }

    fun onPasswordChanged() {
        if(username != null) {
            if(passwordValue != null) {
                login_form_submit_button.isEnabled = true
            }
            else {
                login_form_submit_button.isEnabled = false
            }
        }
        else {
            if(passwordValue != null) {
                login_form_submit_button.isEnabled = false
            }
            else {
                login_form_submit_button.isEnabled = false
            }
        }
    }
}

class ProductionLoginService(val loginApi: LoginApi) {
    fun login(username: String, password: String, onLoggedIn: ()->Unit) {}
}
class DebugLoginService {
    fun login(onLoggedIn: ()->Unit) {}
}