MainActivity.kt

class MainActivity : AppCompatActivity() {
    
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        
    }
    
    // Other Methods
    
    private val simpleContractRegistration = registerForActivityResult(SimpleContract()) {resultStr ->
        if (resultStr == null)
            Toast.makeText(this, "Nothing selected / User Cancelled", Toast.LENGTH_SHORT).show()
        else
            Toast.makeText(this, "Selected value is $resultStr", Toast.LENGTH_SHORT).show()
    }
}