1 /*
2  * Copyright (C) 2017 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 com.android.tv.settings.connectivity.util;
18 
19 
20 import androidx.fragment.app.Fragment;
21 
22 /**
23  * State used by {@link StateMachine}.
24  */
25 public interface State {
26 
27     /**
28      * Process when moving forward.
29      */
processForward()30     void processForward();
31 
32     /**
33      * Process when moving backward.
34      */
processBackward()35     void processBackward();
36 
37     /**
38      * Listener for sending notification about state completion.
39      */
40     interface StateCompleteListener {
onComplete(State caller, @StateMachine.Event int event)41         void onComplete(State caller, @StateMachine.Event int event);
42 
onComplete(Fragment caller, @StateMachine.Event int event)43         void onComplete(Fragment caller, @StateMachine.Event int event);
44     }
45 
46     /**
47      * Listener for sending notification about fragment change.
48      */
49     interface FragmentChangeListener {
onFragmentChange(Fragment newFragment, boolean movingForward)50         void onFragmentChange(Fragment newFragment, boolean movingForward);
51     }
52 
53     /**
54      * @return the corresponding fragment for current state. If there is no corresponding fragment,
55      * return null.
56      */
getFragment()57     Fragment getFragment();
58 }
59