how to properly implement Parcelable with an ArrayList<Parcelable>?

Question

I am having trouble making my class Parcelable. The trouble is, I am trying to write to the parcel a member in the class which is an ArrayList<Parcelable> object. The ArrayList is Serializable, and the objects (ZigBeeDev) in the list are Parcelable.

Here is the relevant code:

package com.gnychis.coexisyst;

import java.util.ArrayList;
import java.util.Iterator;

import android.os.Parcel;
import android.os.Parcelable;

public class ZigBeeNetwork implements Parcelable {

    public String _mac;             // the source address (of the coordinator?)
    public String _pan;             // the network address
    public int _band;               // the channel
    ArrayList<Integer> _lqis;       // link quality indicators (to all devices?)
    ArrayList<ZigBeeDev> _devices;  // the devices in the network

    public void writeToParcel(Parcel out, int flags) {
        out.writeString(_mac);
        out.writeString(_pan);
        out.writeInt(_band);
        out.writeSerializable(_lqis);
        out.writeParcelable(_devices, 0);  // help here
    }

    private ZigBeeNetwork(Parcel in) {
        _mac = in.readString();
        _pan = in.readString();
        _band = in.readInt();
        _lqis = (ArrayList<Integer>) in.readSerializable();
        _devices = in.readParcelable(ZigBeeDev.class.getClassLoader());  // help here
    }

    public int describeContents() {
        return this.hashCode();
    }

    public static final Parcelable.Creator<ZigBeeNetwork> CREATOR = 
            new Parcelable.Creator<ZigBeeNetwork>() {
        public ZigBeeNetwork createFromParcel(Parcel in) {
            return new ZigBeeNetwork(in);
        }

        public ZigBeeNetwork[] newArray(int size) {
            return new ZigBeeNetwork[size];
        }
    };

    //...
}

I have marked two spots "// help here" to understand how to properly write to the parcel and how to reconstruct it. If ZigBeeDev is Parcelable (properly tested), how do I do this properly?

Answer 1

You almost got it !

You just need to do :

public void writeToParcel(Parcel out, int flags) {
    out.writeString(_mac);
    out.writeString(_pan);
    out.writeInt(_band);
    out.writeSerializable(_lqis);
    out.writeTypedList(_devices);
}

private ZigBeeNetwork(Parcel in) {
    _mac = in.readString();
    _pan = in.readString();
    _band = in.readInt();
    _lqis = (ArrayList<Integer>) in.readSerializable();
    in.readTypedList(_devices, ZigBeeDev.CREATOR);
}

That's all!

For your list of Integer, you can also do :

out.writeList(_lqis);
_lqis = new ArrayList<>();
in.readList(_lqis Integer.class.getClassLoader());

It should work.