loops - android parcelable referencing another parcelable circular dependence

Question

Rather simple scenario really, but I could not find anything related on Google so here goes:

class ContainerClass implements Parcelable {
  List<ItemClass> _items;
  (...)

  public void writeToParcel( Parcel p, int args ) {
    p.writeList( _items );
    (...)
  }
}

class ItemClass implements Parcelable {
  ContainerClass _containerRef;      
  (...)

  public void writeToParcel( Parcel p, int args ) {
    p.writeParcelable( _containerRef );
    (...)
  }      
}

This will inevitably loop and overflow the stack.

My question: How am I supposed to deal with a situation where I have to pass an object of the above types through to a new Activity.

(For CommonsWare) Parcelable implementation does indeed not seem to check for, and avoid circular dependencies. Stacktrace with classnames replaced by above names:

08-12 10:17:45.233    5590-5590/com.package E/AndroidRuntime: FATAL EXCEPTION: main
        java.lang.StackOverflowError
        at com.package.ContainerClass.writeToParcel(ContainerClass.java:139)
        at android.os.Parcel.writeParcelable(Parcel.java:1254)
        at com.package.ItemClass.writeToParcel(ItemClass.java:182)
        at android.os.Parcel.writeParcelable(Parcel.java:1254)
        at android.os.Parcel.writeValue(Parcel.java:1173)
        at android.os.Parcel.writeList(Parcel.java:622)
        at com.package.ContainerClass.writeToParcel(ContainerClass.java:144)
        at android.os.Parcel.writeParcelable(Parcel.java:1254)
        at com.package.ItemClass.writeToParcel(ItemClass.java:182)
        at android.os.Parcel.writeParcelable(Parcel.java:1254)
        at android.os.Parcel.writeValue(Parcel.java:1173)
        at android.os.Parcel.writeList(Parcel.java:622)

Answer 1

This will inevitably loop and overflow the stack.

AFAIK, the parceling process does not handle circular object graphs. I just filed an issue to get this better documented.

One workaround is to not do p.writeParcelable( _containerRef );. Instead, in ContainerClass, in your ContainerClass(Parcel in) constructor (or however your CREATOR is handling it), after reading in your _items list, iterate over that list and tell each child about its parent.