Dispose a resource [A]

WeatherActivity.kt

class WeatherActivity : AppCompatActivity() {

    private val thermometer = Thermometer.getInstance()
    private var disposable: Disposable? = null

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        disposable = thermometer
            .observeTemperature()
            .subscribe { celsius -> /* Display in a TextView */ }
    }
    
    overrie fun onDestroy() {
        disposable?.apply { dispose() } // Release
        super.onDestroy()
    }
}