1 /*
2  * Copyright (C) 2015 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 package com.android.messaging.ui;
17 
18 import android.os.Parcelable;
19 
20 /**
21  * Wraps around functionality to save, restore and reset a particular UI component's state.
22  */
23 public interface PersistentInstanceState {
24     /**
25      * Saves necessary information about the current state of the instance to later restore
26      * the instance to its original state.
27      */
saveState()28     Parcelable saveState();
29 
30     /**
31      * Given a previously saved instance state, attempt to restore to its original view state.
32      */
restoreState(Parcelable restoredState)33     void restoreState(Parcelable restoredState);
34 
35     /**
36      * Called when any current/preserved state should be reset to zero state.
37      */
resetState()38     void resetState();
39 }
40