1 /*
2  * Copyright (C) 2019 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 static com.android.systemui.statusbar.notification.row.NotificationContentInflater.FLAG_CONTENT_VIEW_CONTRACTED;
20 import static com.android.systemui.statusbar.notification.row.NotificationContentInflater.FLAG_CONTENT_VIEW_EXPANDED;
21 import static com.android.systemui.statusbar.notification.stack.NotificationChildrenContainer.NUMBER_OF_CHILDREN_WHEN_CHILDREN_EXPANDED;
22 
23 import com.android.systemui.statusbar.notification.collection.NotifPipeline;
24 import com.android.systemui.statusbar.notification.collection.NotificationEntry;
25 import com.android.systemui.statusbar.notification.row.ExpandableNotificationRow;
26 import com.android.systemui.statusbar.notification.row.RowContentBindParams;
27 import com.android.systemui.statusbar.notification.row.RowContentBindStage;
28 
29 import java.util.List;
30 import java.util.Map;
31 
32 import javax.inject.Inject;
33 
34 /**
35  * Controller that binds/unbinds views content views on notification group children.
36  *
37  * We currently only show a limited number of notification children even if more exist, so we
38  * can save memory by freeing content views when they're not visible and binding them again when
39  * they get close to being visible.
40  *
41  * Eventually, when {@link NotifPipeline} takes over as the new notification pipeline, we'll have
42  * more control over which notifications even make it to inflation in the first place and be able
43  * to enforce this at an earlier stage at the level of the {@link ExpandableNotificationRow}, but
44  * for now, we're just doing it at the level of content views.
45  */
46 public class DynamicChildBindController {
47     private final RowContentBindStage mStage;
48     private final int mChildBindCutoff;
49 
50     @Inject
DynamicChildBindController(RowContentBindStage stage)51     public DynamicChildBindController(RowContentBindStage stage) {
52         this(stage, CHILD_BIND_CUTOFF);
53     }
54 
55     /**
56      * @param childBindCutoff the cutoff where we no longer bother having content views bound
57      */
DynamicChildBindController( RowContentBindStage stage, int childBindCutoff)58     DynamicChildBindController(
59             RowContentBindStage stage,
60             int childBindCutoff) {
61         mStage = stage;
62         mChildBindCutoff = childBindCutoff;
63     }
64 
65     /**
66      * Update the content views, unbinding content views on children that won't be visible
67      * and binding content views on children that will be visible eventually and previously unbound
68      * children that are no longer children.
69      *
70      * @param groupNotifs map of top-level notifs to their children, if any
71      */
updateContentViews( Map<NotificationEntry, List<NotificationEntry>> groupNotifs)72     public void updateContentViews(
73             Map<NotificationEntry, List<NotificationEntry>> groupNotifs) {
74         for (NotificationEntry entry : groupNotifs.keySet()) {
75             List<NotificationEntry> children = groupNotifs.get(entry);
76             if (children == null) {
77                 if (!hasContent(entry)) {
78                     // Case where child is updated to be top level
79                     bindContent(entry);
80                 }
81                 continue;
82             }
83             for (int j = 0; j < children.size(); j++) {
84                 NotificationEntry childEntry = children.get(j);
85                 if (j >= mChildBindCutoff) {
86                     if (hasContent(childEntry)) {
87                         freeContent(childEntry);
88                     }
89                 } else {
90                     if (!hasContent(childEntry)) {
91                         bindContent(childEntry);
92                     }
93                 }
94             }
95         }
96     }
97 
hasContent(NotificationEntry entry)98     private boolean hasContent(NotificationEntry entry) {
99         ExpandableNotificationRow row = entry.getRow();
100         return row.getPrivateLayout().getContractedChild() != null
101                 || row.getPrivateLayout().getExpandedChild() != null;
102     }
103 
freeContent(NotificationEntry entry)104     private void freeContent(NotificationEntry entry) {
105         RowContentBindParams params = mStage.getStageParams(entry);
106         params.markContentViewsFreeable(FLAG_CONTENT_VIEW_CONTRACTED);
107         params.markContentViewsFreeable(FLAG_CONTENT_VIEW_EXPANDED);
108         mStage.requestRebind(entry, null);
109     }
110 
bindContent(NotificationEntry entry)111     private void bindContent(NotificationEntry entry) {
112         RowContentBindParams params = mStage.getStageParams(entry);
113         params.requireContentViews(FLAG_CONTENT_VIEW_CONTRACTED);
114         params.requireContentViews(FLAG_CONTENT_VIEW_EXPANDED);
115         mStage.requestRebind(entry, null);
116     }
117 
118     /**
119      * How big the buffer of extra views we keep around to be ready to show when we do need to
120      * dynamically inflate.
121      */
122     private static final int EXTRA_VIEW_BUFFER_COUNT = 1;
123 
124     private static final int CHILD_BIND_CUTOFF =
125             NUMBER_OF_CHILDREN_WHEN_CHILDREN_EXPANDED + EXTRA_VIEW_BUFFER_COUNT;
126 }
127