MainActivity.kt

import kotlinx.android.synthetic.main.activity_main.*

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        // Create view model that normally would be created in an injection system such as
        // by viewModel, or Dagger, or Hilt.
        // For our purposes of discussion we are just instantiating here as it does not matter
        // where our BusinessLogicCenter (ViewModel) comes from.
        val viewModel = ProductInfoBusinessLogicCenterViewModel()
        viewModel.productInfo.observe(this, { displayObject ->
            // Using kotlin synthetics we simply set the text.
            productName.text = displayObject.productName
            price.text = displayObject.price
        })
    }
}