We’d like to pass an Object from one Activity to another in Java Android, there are two ways to do this operation, the first one is to use a Serializable Object while the second one is to use a Parcelable Object.

It is strongly recommended due to performance issues to use the first solution.

Imagine you have a Song Custom Object, you need implements Parcelable in your Song class:

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

public class Song implements Parcelable {
    private String title;
    private String author;
    private String album;
    private String genre;
    private String location;

    public Song (String title, String author, String album, String genre, String location) {
        this.title = title;
        this.author=author;
        this.album=album;
        this.genre=genre;
        this.location=location;
    }

    public Song(Parcel in) { //Constructor when loading from Parcel
        title = in.readString();
        author = in.readString();
        album = in.readString();
        genre = in.readString();
        location = in.readString();
    }

//Getters and Setters

    public String getAlbum() {
        return album;
    }

    public void setAlbum(String album) {
        this.album = album;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getAuthor() {
        return author;
    }

    public void setAuthor(String author) {
        this.author = author;
    }

    public String getGenre() {
        return genre;
    }

    public void setGenre(String genre) {
        this.genre = genre;
    }

    public String getLocation() {
        return location;
    }

    public void setLocation(String location) {
        this.location = location;
    }

//Required method, but not used
    @Override
    public int describeContents() {
        return 0;
    }

    @Override
    public void writeToParcel(Parcel dest, int flags) {

//When Parcel this Object write every variable to Parcel dest
        dest.writeString(title);
        dest.writeString(author);
        dest.writeString(album);
        dest.writeString(genre);
        dest.writeString(location);
    }

//Parcelable Creator, every Parcelable Object should implement this method.

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

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

Then in the first Activity:

ArrayList<Song> passedList = new ArrayList <Song>();
Intent intent = new Intent(context, SecondActivity.class);
String pkg = getPackageName();
intent.putExtra(pkg+”values”, passedList);
startActivity(intent);

In the second Activity:

ArrayList<Song> passedValues = getIntent().getParcelableArrayListExtra(pkg+”values”);