1 /*
2  * Copyright (C) 2020 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.settings.accessibility;
18 
19 import android.content.ContentResolver;
20 import android.content.Context;
21 import android.database.ContentObserver;
22 import android.provider.Settings;
23 
24 import androidx.annotation.IntDef;
25 
26 import com.android.settings.R;
27 
28 import com.google.common.primitives.Ints;
29 
30 import java.lang.annotation.Retention;
31 import java.lang.annotation.RetentionPolicy;
32 
33 /** Class to provide magnification capabilities. */
34 public final class MagnificationCapabilities {
35 
36     private static final String KEY_CAPABILITY =
37             Settings.Secure.ACCESSIBILITY_MAGNIFICATION_CAPABILITY;
38 
39     /**
40      * Annotation for supported magnification mode.
41      *
42      * @see Settings.Secure#ACCESSIBILITY_MAGNIFICATION_CAPABILITY
43      */
44     @Retention(RetentionPolicy.SOURCE)
45     @IntDef({
46             MagnificationMode.NONE,
47             MagnificationMode.FULLSCREEN,
48             MagnificationMode.WINDOW,
49             MagnificationMode.ALL,
50     })
51 
52     public @interface MagnificationMode {
53         int NONE = Settings.Secure.ACCESSIBILITY_MAGNIFICATION_MODE_NONE;
54         int FULLSCREEN = Settings.Secure.ACCESSIBILITY_MAGNIFICATION_MODE_FULLSCREEN;
55         int WINDOW = Settings.Secure.ACCESSIBILITY_MAGNIFICATION_MODE_WINDOW;
56         int ALL = Settings.Secure.ACCESSIBILITY_MAGNIFICATION_MODE_ALL;
57     }
58 
59     /**
60      * Gets the summary for the given {@code capabilities}.
61      *
62      * @param context A {@link Context}.
63      * @param capabilities Magnification capabilities {@link MagnificationMode}
64      * @return The summary text represents the given capabilities
65      */
getSummary(Context context, @MagnificationMode int capabilities)66     public static String getSummary(Context context, @MagnificationMode int capabilities) {
67         final String[] summaries = context.getResources().getStringArray(
68                 R.array.magnification_mode_summaries);
69         final int[] values = context.getResources().getIntArray(
70                 R.array.magnification_mode_values);
71 
72         final int idx = Ints.indexOf(values, capabilities);
73         return summaries[idx == /* no index exist */ -1 ? 0 : idx];
74     }
75 
76     /**
77      * Sets the magnification capabilities {@link MagnificationMode} to settings key. This
78      * overwrites any existing capabilities.
79      *
80      * @param context      A {@link Context}.
81      * @param capabilities Magnification capabilities {@link MagnificationMode}
82      */
setCapabilities(Context context, @MagnificationMode int capabilities)83     public static void setCapabilities(Context context, @MagnificationMode int capabilities) {
84         final ContentResolver contentResolver = context.getContentResolver();
85 
86         Settings.Secure.putIntForUser(contentResolver, KEY_CAPABILITY, capabilities,
87                 contentResolver.getUserId());
88     }
89 
90     /**
91      * Returns the magnification capabilities {@link MagnificationMode} from setting's key. May be
92      * default value {@link MagnificationMode#FULLSCREEN} if not set.
93      *
94      * @param context A {@link Context}.
95      * @return The magnification capabilities {@link MagnificationMode}
96      */
97     @MagnificationMode
getCapabilities(Context context)98     public static int getCapabilities(Context context) {
99         final ContentResolver contentResolver = context.getContentResolver();
100 
101         return Settings.Secure.getIntForUser(contentResolver, KEY_CAPABILITY,
102                 MagnificationMode.FULLSCREEN, contentResolver.getUserId());
103     }
104 
105     /**
106      * Register an observer class that gets callbacks when magnification capabilities changes.
107      *
108      * @param context A {@link Context}.
109      * @param contentObserver The object that receives callbacks when changes occur.
110      */
registerObserver(Context context, ContentObserver contentObserver)111     public static void registerObserver(Context context, ContentObserver contentObserver) {
112         context.getContentResolver().registerContentObserver(
113                 Settings.Secure.getUriFor(KEY_CAPABILITY),
114                 /* notifyForDescendants= */ false,
115                 contentObserver);
116     }
117 
118     /**
119      * Unregisters a magnification capabilities change observer.
120      *
121      * @param context A {@link Context}.
122      * @param contentObserver The previously registered observer that is no longer needed.
123      */
unregisterObserver(Context context, ContentObserver contentObserver)124     public static void unregisterObserver(Context context, ContentObserver contentObserver) {
125         context.getContentResolver().unregisterContentObserver(contentObserver);
126     }
127 
MagnificationCapabilities()128     private MagnificationCapabilities() {}
129 }
130