1 /*
2  * Copyright (C) 2018 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.car.settings.sound;
18 
19 import android.content.Context;
20 import android.content.res.TypedArray;
21 import android.content.res.XmlResourceParser;
22 import android.media.AudioAttributes;
23 import android.util.AttributeSet;
24 import android.util.SparseArray;
25 import android.util.Xml;
26 
27 import androidx.annotation.DrawableRes;
28 import androidx.annotation.StringRes;
29 import androidx.annotation.XmlRes;
30 
31 import com.android.car.settings.R;
32 import com.android.car.settings.common.Logger;
33 
34 import org.xmlpull.v1.XmlPullParserException;
35 
36 import java.io.IOException;
37 
38 /**
39  * Parses the xml file which specifies which Audio usages should be considered by sound settings.
40  */
41 public class VolumeItemParser {
42     private static final Logger LOG = new Logger(VolumeItemParser.class);
43 
44     private static final String XML_TAG_VOLUME_ITEMS = "carVolumeItems";
45     private static final String XML_TAG_VOLUME_ITEM = "item";
46 
47     /**
48      * Parses the volume items listed in the xml resource provided. This is returned as a sparse
49      * array which is keyed by the rank (the order in which the volume item appears in the xml
50      * resrouce).
51      */
loadAudioUsageItems(Context context, @XmlRes int volumeItemsXml)52     public static SparseArray<VolumeItem> loadAudioUsageItems(Context context,
53             @XmlRes int volumeItemsXml) {
54         SparseArray<VolumeItem> volumeItems = new SparseArray<>();
55         try (XmlResourceParser parser = context.getResources().getXml(volumeItemsXml)) {
56             AttributeSet attrs = Xml.asAttributeSet(parser);
57             int type;
58             // Traverse to the first start tag.
59             while ((type = parser.next()) != XmlResourceParser.END_DOCUMENT
60                     && type != XmlResourceParser.START_TAG) {
61                 continue;
62             }
63 
64             if (!XML_TAG_VOLUME_ITEMS.equals(parser.getName())) {
65                 throw new RuntimeException("Meta-data does not start with carVolumeItems tag");
66             }
67             int outerDepth = parser.getDepth();
68             int rank = 0;
69             while ((type = parser.next()) != XmlResourceParser.END_DOCUMENT
70                     && (type != XmlResourceParser.END_TAG || parser.getDepth() > outerDepth)) {
71                 if (type == XmlResourceParser.END_TAG) {
72                     continue;
73                 }
74                 if (XML_TAG_VOLUME_ITEM.equals(parser.getName())) {
75                     TypedArray item = context.getResources().obtainAttributes(
76                             attrs, R.styleable.carVolumeItems_item);
77                     int usage = item.getInt(R.styleable.carVolumeItems_item_usage, -1);
78                     if (usage >= 0) {
79                         volumeItems.put(usage, new VolumeItemParser.VolumeItem(
80                                 usage, rank,
81                                 item.getResourceId(R.styleable.carVolumeItems_item_titleText, 0),
82                                 item.getResourceId(R.styleable.carVolumeItems_item_icon, 0)));
83                         rank++;
84                     }
85                     item.recycle();
86                 }
87             }
88         } catch (XmlPullParserException | IOException e) {
89             LOG.e("Error parsing volume groups configuration", e);
90         }
91         return volumeItems;
92     }
93 
94     /**
95      * Wrapper class which contains information to render volume item on UI.
96      */
97     public static class VolumeItem {
98         @AudioAttributes.AttributeUsage
99         private final int mUsage;
100         private final int mRank;
101         @StringRes
102         private final int mTitle;
103         @DrawableRes
104         private final int mIcon;
105 
106         /** Constructs the VolumeItem container with the given values. */
VolumeItem(@udioAttributes.AttributeUsage int usage, int rank, @StringRes int title, @DrawableRes int icon)107         public VolumeItem(@AudioAttributes.AttributeUsage int usage, int rank,
108                 @StringRes int title, @DrawableRes int icon) {
109             mUsage = usage;
110             mRank = rank;
111             mTitle = title;
112             mIcon = icon;
113         }
114 
115         /**
116          * Usage is used to represent what purpose the sound is used for. The values should be
117          * defined within AudioAttributes.USAGE_*.
118          */
getUsage()119         public int getUsage() {
120             return mUsage;
121         }
122 
123         /**
124          * Rank represents the order in which the usage appears in
125          * {@link R.xml#car_volume_items}. This order is used to determine which title and icon
126          * should be used for each audio group. The lowest rank has the highest precedence.
127          */
getRank()128         public int getRank() {
129             return mRank;
130         }
131 
132         /** Title which should be used for the seek bar preference. */
getTitle()133         public int getTitle() {
134             return mTitle;
135         }
136 
137         /** Icon which should be used for the seek bar preference. */
getIcon()138         public int getIcon() {
139             return mIcon;
140         }
141     }
142 }
143