The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2006 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | package android.os; |
| 18 | |
| 19 | /** |
| 20 | * Interface for classes whose instances can be written to |
| 21 | * and restored from a {@link Parcel}. Classes implementing the Parcelable |
| 22 | * interface must also have a static field called <code>CREATOR</code>, which |
| 23 | * is an object implementing the {@link Parcelable.Creator Parcelable.Creator} |
| 24 | * interface. |
| 25 | * |
| 26 | * <p>A typical implementation of Parcelable is:</p> |
| 27 | * |
| 28 | * <pre> |
| 29 | * public class MyParcelable implements Parcelable { |
| 30 | * private int mData; |
Bjorn Bringert | d8919f0 | 2009-10-28 19:16:24 +0000 | [diff] [blame] | 31 | * |
| 32 | * public int describeContents() { |
| 33 | * return 0; |
| 34 | * } |
| 35 | * |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 36 | * public void writeToParcel(Parcel out, int flags) { |
| 37 | * out.writeInt(mData); |
| 38 | * } |
| 39 | * |
Bjorn Bringert | d8919f0 | 2009-10-28 19:16:24 +0000 | [diff] [blame] | 40 | * public static final Parcelable.Creator<MyParcelable> CREATOR |
| 41 | * = new Parcelable.Creator<MyParcelable>() { |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 42 | * public MyParcelable createFromParcel(Parcel in) { |
| 43 | * return new MyParcelable(in); |
| 44 | * } |
| 45 | * |
| 46 | * public MyParcelable[] newArray(int size) { |
| 47 | * return new MyParcelable[size]; |
| 48 | * } |
Bjorn Bringert | d8919f0 | 2009-10-28 19:16:24 +0000 | [diff] [blame] | 49 | * }; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 50 | * |
| 51 | * private MyParcelable(Parcel in) { |
| 52 | * mData = in.readInt(); |
| 53 | * } |
| 54 | * }</pre> |
| 55 | */ |
| 56 | public interface Parcelable { |
| 57 | /** |
| 58 | * Flag for use with {@link #writeToParcel}: the object being written |
| 59 | * is a return value, that is the result of a function such as |
| 60 | * "<code>Parcelable someFunction()</code>", |
| 61 | * "<code>void someFunction(out Parcelable)</code>", or |
| 62 | * "<code>void someFunction(inout Parcelable)</code>". Some implementations |
| 63 | * may want to release resources at this point. |
| 64 | */ |
| 65 | public static final int PARCELABLE_WRITE_RETURN_VALUE = 0x0001; |
| 66 | |
| 67 | /** |
| 68 | * Bit masks for use with {@link #describeContents}: each bit represents a |
| 69 | * kind of object considered to have potential special significance when |
| 70 | * marshalled. |
| 71 | */ |
| 72 | public static final int CONTENTS_FILE_DESCRIPTOR = 0x0001; |
| 73 | |
| 74 | /** |
| 75 | * Describe the kinds of special objects contained in this Parcelable's |
| 76 | * marshalled representation. |
| 77 | * |
| 78 | * @return a bitmask indicating the set of special object types marshalled |
| 79 | * by the Parcelable. |
| 80 | */ |
| 81 | public int describeContents(); |
| 82 | |
| 83 | /** |
| 84 | * Flatten this object in to a Parcel. |
| 85 | * |
| 86 | * @param dest The Parcel in which the object should be written. |
| 87 | * @param flags Additional flags about how the object should be written. |
| 88 | * May be 0 or {@link #PARCELABLE_WRITE_RETURN_VALUE}. |
| 89 | */ |
| 90 | public void writeToParcel(Parcel dest, int flags); |
| 91 | |
| 92 | /** |
| 93 | * Interface that must be implemented and provided as a public CREATOR |
| 94 | * field that generates instances of your Parcelable class from a Parcel. |
| 95 | */ |
| 96 | public interface Creator<T> { |
| 97 | /** |
| 98 | * Create a new instance of the Parcelable class, instantiating it |
| 99 | * from the given Parcel whose data had previously been written by |
| 100 | * {@link Parcelable#writeToParcel Parcelable.writeToParcel()}. |
| 101 | * |
| 102 | * @param source The Parcel to read the object's data from. |
| 103 | * @return Returns a new instance of the Parcelable class. |
| 104 | */ |
| 105 | public T createFromParcel(Parcel source); |
| 106 | |
| 107 | /** |
| 108 | * Create a new array of the Parcelable class. |
| 109 | * |
| 110 | * @param size Size of the array. |
| 111 | * @return Returns an array of the Parcelable class, with every entry |
| 112 | * initialized to null. |
| 113 | */ |
| 114 | public T[] newArray(int size); |
| 115 | } |
Dianne Hackborn | b46ed76 | 2011-06-02 18:33:15 -0700 | [diff] [blame] | 116 | |
| 117 | /** |
| 118 | * Specialization of {@link Creator} that allows you to receive the |
| 119 | * ClassLoader the object is being created in. |
| 120 | */ |
| 121 | public interface ClassLoaderCreator<T> extends Creator<T> { |
| 122 | /** |
| 123 | * Create a new instance of the Parcelable class, instantiating it |
| 124 | * from the given Parcel whose data had previously been written by |
| 125 | * {@link Parcelable#writeToParcel Parcelable.writeToParcel()} and |
| 126 | * using the given ClassLoader. |
| 127 | * |
| 128 | * @param source The Parcel to read the object's data from. |
| 129 | * @param loader The ClassLoader that this object is being created in. |
| 130 | * @return Returns a new instance of the Parcelable class. |
| 131 | */ |
| 132 | public T createFromParcel(Parcel source, ClassLoader loader); |
| 133 | } |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 134 | } |