Is it possible to achieve encapsulation of the con...

# android

[arekolek]

Is it possible to achieve encapsulation of the concrete type:

public class DataViewModel {
    private MutableLiveData<String> data = new MutableLiveData<>();

    public LiveData<String> getData() {
        return data;
    }
}

in Kotlin without resorting to having a backing property?

class DataViewModel {
    private val _data = MutableLiveData<String>()

    val data: LiveData<String> get() = _data
}

[stantronic]

You could use the JvmField annotation https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.jvm/-jvm-field/

[kingsley]

No. He’s trying to hide the fact that the data is mutable, and rather expose it as a simple LiveData

[stantronic]

yes, but you could do that by making the private val a Jvm field, which would mean no getters and setters, and would be equivalent to the java code.

[kingsley]

A private val as shown by Arek above already omits getters/setters, so there’s no need of a @JvmField.
In fact, you cannot combine @JvmField and private val in the same declaration

[stantronic]

Ok. Good to know 🙂 In which case I don’t see the advantage of removing the backing property

[kingsley]

Exactly. There’s always a backing property anyway. It’s just sometimes more verbose 🙂

[arekolek]

Either I missed that (https://kotlinlang.org/docs/reference/properties.html#backing-properties), or it was added to the documentation recently, so thanks for mentioning that!