Package android.os

Interface Parcelable

public interface Parcelable

Interface for classes whose instances can be written to and restored from a Parcel. Classes implementing the Parcelable interface must also have a non-null static field called CREATOR of a type that implements the Parcelable.Creator interface.

A typical implementation of Parcelable is:

 public class MyParcelable implements Parcelable {
     private int mData;

     public int describeContents() {
         return 0;
     }

     public void writeToParcel(Parcel out, int flags) {
         out.writeInt(mData);
     }

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

         public MyParcelable[] newArray(int size) {
             return new MyParcelable[size];
         }
     };
     
     private MyParcelable(Parcel in) {
         mData = in.readInt();
     }
 }

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	Parcelable.ClassLoaderCreator<T>	Specialization of Parcelable.Creator that allows you to receive the ClassLoader the object is being created in.
static interface	Parcelable.ContentsFlags
static interface	Parcelable.Creator<T>	Interface that must be implemented and provided as a public CREATOR field that generates instances of your Parcelable class from a Parcel.
static interface	Parcelable.WriteFlags

Field Summary

Fields

Modifier and Type	Field	Description
static int	CONTENTS_FILE_DESCRIPTOR	Descriptor bit used with describeContents(): indicates that the Parcelable object's flattened representation includes a file descriptor.
static int	PARCELABLE_ELIDE_DUPLICATES	Flag for use with writeToParcel(android.os.Parcel, int): a parent object will take care of managing duplicate state/data that is nominally replicated across its inner data members.
static int	PARCELABLE_WRITE_RETURN_VALUE	Flag for use with writeToParcel(android.os.Parcel, int): the object being written is a return value, that is the result of a function such as "Parcelable someFunction()", "void someFunction(out Parcelable)", or "void someFunction(inout Parcelable)".

Method Summary

Modifier and Type	Method	Description
int	describeContents()	Describe the kinds of special objects contained in this Parcelable instance's marshaled representation.
void	writeToParcel(android.os.Parcel dest, int flags)	Flatten this object in to a Parcel.

Field Detail

PARCELABLE_WRITE_RETURN_VALUE

static final int PARCELABLE_WRITE_RETURN_VALUE

Flag for use with writeToParcel(android.os.Parcel, int): the object being written is a return value, that is the result of a function such as "Parcelable someFunction()", "void someFunction(out Parcelable)", or "void someFunction(inout Parcelable)". Some implementations may want to release resources at this point.

See Also:

Constant Field Values

PARCELABLE_ELIDE_DUPLICATES

static final int PARCELABLE_ELIDE_DUPLICATES

Flag for use with writeToParcel(android.os.Parcel, int): a parent object will take care of managing duplicate state/data that is nominally replicated across its inner data members. This flag instructs the inner data types to omit that data during marshaling. Exact behavior may vary on a case by case basis.

See Also:

Constant Field Values

CONTENTS_FILE_DESCRIPTOR

static final int CONTENTS_FILE_DESCRIPTOR

Descriptor bit used with describeContents(): indicates that the Parcelable object's flattened representation includes a file descriptor.

See Also:

describeContents(), Constant Field Values

Method Detail

describeContents

int describeContents()

Describe the kinds of special objects contained in this Parcelable instance's marshaled representation. For example, if the object will include a file descriptor in the output of writeToParcel(Parcel, int), the return value of this method must include the CONTENTS_FILE_DESCRIPTOR bit.

Returns:

a bitmask indicating the set of special object types marshaled by this Parcelable object instance.

writeToParcel

void writeToParcel(android.os.Parcel dest,
                   int flags)

Flatten this object in to a Parcel.

Parameters:

dest - The Parcel in which the object should be written.

flags - Additional flags about how the object should be written. May be 0 or PARCELABLE_WRITE_RETURN_VALUE.