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.statusbar.notification;
18 
19 import android.view.View;
20 import android.view.ViewGroup;
21 
22 import com.android.internal.annotations.VisibleForTesting;
23 import com.android.systemui.statusbar.notification.row.ExpandableNotificationRow;
24 
25 /**
26  * An observer that listens to the above shelf state and can notify listeners
27  */
28 public class AboveShelfObserver implements AboveShelfChangedListener {
29 
30     private final ViewGroup mHostLayout;
31     private boolean mHasViewsAboveShelf = false;
32     private HasViewAboveShelfChangedListener mListener;
33 
AboveShelfObserver(ViewGroup hostLayout)34     public AboveShelfObserver(ViewGroup hostLayout) {
35         mHostLayout = hostLayout;
36     }
37 
setListener(HasViewAboveShelfChangedListener listener)38     public void setListener(HasViewAboveShelfChangedListener listener) {
39         mListener = listener;
40     }
41 
42     @Override
onAboveShelfStateChanged(boolean aboveShelf)43     public void onAboveShelfStateChanged(boolean aboveShelf) {
44         boolean hasViewsAboveShelf = aboveShelf;
45         if (!hasViewsAboveShelf && mHostLayout != null) {
46             int n = mHostLayout.getChildCount();
47             for (int i = 0; i < n; i++) {
48                 View child = mHostLayout.getChildAt(i);
49                 if (child instanceof ExpandableNotificationRow) {
50                     if (((ExpandableNotificationRow) child).isAboveShelf()) {
51                         hasViewsAboveShelf = true;
52                         break;
53                     }
54                 }
55             }
56         }
57         if (mHasViewsAboveShelf != hasViewsAboveShelf) {
58             mHasViewsAboveShelf = hasViewsAboveShelf;
59             if (mListener != null) {
60                 mListener.onHasViewsAboveShelfChanged(hasViewsAboveShelf);
61             }
62         }
63     }
64 
65     @VisibleForTesting
hasViewsAboveShelf()66     boolean hasViewsAboveShelf() {
67         return mHasViewsAboveShelf;
68     }
69 
70     public interface HasViewAboveShelfChangedListener {
onHasViewsAboveShelfChanged(boolean hasViewsAboveShelf)71         void onHasViewsAboveShelfChanged(boolean hasViewsAboveShelf);
72     }
73 }
74