parcelable

Parcelable is an interface in the Android software development kit (SDK) that allows objects to be passed between different components of an Android application or between different applications. It is used to serialize and deserialize objects, enabling them to be written to and read from a Parcel, which is a container for a message (data and object references) that can be sent through an IBinder.

The Parcelable interface requires implementing two methods: writeToParcel and describeContents. The writeToParcel method is used to write the object's data to a Parcel, while the describeContents method is used to provide information about the contents of the Parcel. The CREATOR field is also required, which is an instance of the Parcelable.Creator interface that is used to create instances of the Parcelable class from a Parcel.

Parcelable is often used to pass complex objects between activities, fragments, or services in an Android application. It is more efficient than using Java serialization because it avoids the overhead of creating a byte stream and can directly write primitive data types and arrays to the Parcel. However, it requires more manual implementation compared to using Java serialization.

Parcelable is not suitable for all use cases. For example, it is not suitable for passing objects between processes because it does not support cross-process communication. In such cases, other serialization mechanisms such as Serializable or Gson may be more appropriate. Additionally, Parcelable is not suitable for passing objects that contain references to other objects, as it does not handle object graphs. In such cases, other serialization mechanisms such as Serializable or Gson may be more appropriate.