ThreadActivity.kt

class ThreadActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_thread)

        val thread = Thread {
            val person = getPersonInfoById(5)
            runOnUiThread {
                progress_bar.visibility = View.GONE
                name.text = person.name
                username.text = person.username
                email.text = person.email
                phone.text = person.phone
            }
        }
        thread.start()
    }

    fun getPersonInfoById(userId: Int): Person {
        val url = "https://jsonplaceholder.typicode.com/users/$userId"
        val inputStream: BufferedReader
        val jsonUrl = URL(url)
        val dc = jsonUrl.openConnection()
        inputStream = BufferedReader(
            InputStreamReader(
                dc.getInputStream()
            )
        )
        var string = ""
        inputStream.readLines().forEach{ string += it }
        val jo = JSONObject(string)
        return Person(
            jo.getString("name"),
            jo.getString("username"),
            jo.getString("email"),
            jo.getString("phone")
        )
    }

    inner class Person(val name: String, val username: String, val email: String, val phone: String)
}