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.systemui.keyguard;
18 
19 import androidx.annotation.NonNull;
20 
21 import java.util.ArrayList;
22 import java.util.Objects;
23 import java.util.function.Consumer;
24 
25 /**
26  * Base class for lifecycles with observers.
27  */
28 public class Lifecycle<T> {
29 
30     private ArrayList<T> mObservers = new ArrayList<>();
31 
addObserver(@onNull T observer)32     public void addObserver(@NonNull T observer) {
33         mObservers.add(Objects.requireNonNull(observer));
34     }
35 
removeObserver(T observer)36     public void removeObserver(T observer) {
37         mObservers.remove(observer);
38     }
39 
dispatch(Consumer<T> consumer)40     public void dispatch(Consumer<T> consumer) {
41         for (int i = 0; i < mObservers.size(); i++) {
42             consumer.accept(mObservers.get(i));
43         }
44     }
45 }
46