Private setter for var in primary constructor

daben107 · October 9, 2018, 3:31am

And in android @Parcelize

All parameters of the primary constructor must be properties ( val / var ), otherwise they can not be (de)serialized

If there is a non-property parameter, it is a compile-time error

github.com

Kotlin/KEEP/blob/master/proposals/extensions/android-parcelable.md#simple-case-completely-automatic-parcelable

# Compiler Extension to Support `android.os.Parcelable`

* **Type**: Design proposal
* **Status**: Accepted
* **Prototype**: Implemented in Kotlin 1.1

## Overview

The `android.os.Parcelable` API requires substantial boilerplate for each parcelable class. In this document, we investigate the possible ways of mitigating this in Kotlin via a compiler extension.

### General difficulties with `Parcelable`

The `android.os.Parcelable` API requires some boilerplate code to be implemented (see [here](https://developer.android.com/reference/android/os/Parcelable.html)):

```java
 public class MyParcelable implements Parcelable {
     private int mData;

     public int describeContents() {
         return 0;

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Private setter for var in primary constructor

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