1 /*
2  * Copyright (C) 2015 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.settingslib.accessibility;
18 
19 import android.accessibilityservice.AccessibilityServiceInfo;
20 import android.content.ComponentName;
21 import android.content.Context;
22 import android.content.pm.ResolveInfo;
23 import android.content.res.Configuration;
24 import android.content.res.Resources;
25 import android.os.UserHandle;
26 import android.provider.Settings;
27 import android.text.TextUtils;
28 import android.util.ArraySet;
29 import android.view.accessibility.AccessibilityManager;
30 
31 import com.android.internal.R;
32 
33 import java.util.Collections;
34 import java.util.HashSet;
35 import java.util.List;
36 import java.util.Locale;
37 import java.util.Set;
38 
39 public class AccessibilityUtils {
40     public static final char ENABLED_ACCESSIBILITY_SERVICES_SEPARATOR = ':';
41 
42     final static TextUtils.SimpleStringSplitter sStringColonSplitter =
43             new TextUtils.SimpleStringSplitter(ENABLED_ACCESSIBILITY_SERVICES_SEPARATOR);
44 
45     /**
46      * @return the set of enabled accessibility services. If there are no services,
47      * it returns the unmodifiable {@link Collections#emptySet()}.
48      */
getEnabledServicesFromSettings(Context context)49     public static Set<ComponentName> getEnabledServicesFromSettings(Context context) {
50         return getEnabledServicesFromSettings(context, UserHandle.myUserId());
51     }
52 
53     /**
54      * @return the set of enabled accessibility services for {@param userId}. If there are no
55      * services, it returns the unmodifiable {@link Collections#emptySet()}.
56      */
getEnabledServicesFromSettings(Context context, int userId)57     public static Set<ComponentName> getEnabledServicesFromSettings(Context context, int userId) {
58         final String enabledServicesSetting = Settings.Secure.getStringForUser(
59                 context.getContentResolver(), Settings.Secure.ENABLED_ACCESSIBILITY_SERVICES,
60                 userId);
61         if (enabledServicesSetting == null) {
62             return Collections.emptySet();
63         }
64 
65         final Set<ComponentName> enabledServices = new HashSet<>();
66         final TextUtils.SimpleStringSplitter colonSplitter = sStringColonSplitter;
67         colonSplitter.setString(enabledServicesSetting);
68 
69         while (colonSplitter.hasNext()) {
70             final String componentNameString = colonSplitter.next();
71             final ComponentName enabledService = ComponentName.unflattenFromString(
72                     componentNameString);
73             if (enabledService != null) {
74                 enabledServices.add(enabledService);
75             }
76         }
77 
78         return enabledServices;
79     }
80 
81     /**
82      * @return a localized version of the text resource specified by resId
83      */
getTextForLocale(Context context, Locale locale, int resId)84     public static CharSequence getTextForLocale(Context context, Locale locale, int resId) {
85         final Resources res = context.getResources();
86         final Configuration config = new Configuration(res.getConfiguration());
87         config.setLocale(locale);
88         final Context langContext = context.createConfigurationContext(config);
89         return langContext.getText(resId);
90     }
91 
92     /**
93      * Changes an accessibility component's state.
94      */
setAccessibilityServiceState(Context context, ComponentName toggledService, boolean enabled)95     public static void setAccessibilityServiceState(Context context, ComponentName toggledService,
96             boolean enabled) {
97         setAccessibilityServiceState(context, toggledService, enabled, UserHandle.myUserId());
98     }
99 
100     /**
101      * Changes an accessibility component's state for {@param userId}.
102      */
setAccessibilityServiceState(Context context, ComponentName toggledService, boolean enabled, int userId)103     public static void setAccessibilityServiceState(Context context, ComponentName toggledService,
104             boolean enabled, int userId) {
105         // Parse the enabled services.
106         Set<ComponentName> enabledServices = AccessibilityUtils.getEnabledServicesFromSettings(
107                 context, userId);
108 
109         if (enabledServices.isEmpty()) {
110             enabledServices = new ArraySet<>(1);
111         }
112 
113         // Determine enabled services and accessibility state.
114         boolean accessibilityEnabled = false;
115         if (enabled) {
116             enabledServices.add(toggledService);
117             // Enabling at least one service enables accessibility.
118             accessibilityEnabled = true;
119         } else {
120             enabledServices.remove(toggledService);
121             // Check how many enabled and installed services are present.
122             Set<ComponentName> installedServices = getInstalledServices(context);
123             for (ComponentName enabledService : enabledServices) {
124                 if (installedServices.contains(enabledService)) {
125                     // Disabling the last service disables accessibility.
126                     accessibilityEnabled = true;
127                     break;
128                 }
129             }
130         }
131 
132         // Update the enabled services setting.
133         StringBuilder enabledServicesBuilder = new StringBuilder();
134         // Keep the enabled services even if they are not installed since we
135         // have no way to know whether the application restore process has
136         // completed. In general the system should be responsible for the
137         // clean up not settings.
138         for (ComponentName enabledService : enabledServices) {
139             enabledServicesBuilder.append(enabledService.flattenToString());
140             enabledServicesBuilder.append(
141                     AccessibilityUtils.ENABLED_ACCESSIBILITY_SERVICES_SEPARATOR);
142         }
143         final int enabledServicesBuilderLength = enabledServicesBuilder.length();
144         if (enabledServicesBuilderLength > 0) {
145             enabledServicesBuilder.deleteCharAt(enabledServicesBuilderLength - 1);
146         }
147         Settings.Secure.putStringForUser(context.getContentResolver(),
148                 Settings.Secure.ENABLED_ACCESSIBILITY_SERVICES,
149                 enabledServicesBuilder.toString(), userId);
150     }
151 
152     /**
153      * Get the name of the service that should be toggled by the accessibility shortcut. Use
154      * an OEM-configurable default if the setting has never been set.
155      *
156      * @param context A valid context
157      * @param userId The user whose settings should be checked
158      *
159      * @return The component name, flattened to a string, of the target service.
160      */
getShortcutTargetServiceComponentNameString( Context context, int userId)161     public static String getShortcutTargetServiceComponentNameString(
162             Context context, int userId) {
163         final String currentShortcutServiceId = Settings.Secure.getStringForUser(
164                 context.getContentResolver(), Settings.Secure.ACCESSIBILITY_SHORTCUT_TARGET_SERVICE,
165                 userId);
166         if (currentShortcutServiceId != null) {
167             return currentShortcutServiceId;
168         }
169         return context.getString(R.string.config_defaultAccessibilityService);
170     }
171 
172     /**
173      * Check if the accessibility shortcut is enabled for a user
174      *
175      * @param context A valid context
176      * @param userId The user of interest
177      * @return {@code true} if the shortcut is enabled for the user. {@code false} otherwise.
178      *         Note that the shortcut may be enabled, but no action associated with it.
179      */
isShortcutEnabled(Context context, int userId)180     public static boolean isShortcutEnabled(Context context, int userId) {
181         return Settings.Secure.getIntForUser(context.getContentResolver(),
182                 Settings.Secure.ACCESSIBILITY_SHORTCUT_ENABLED, 1, userId) == 1;
183     }
184 
getInstalledServices(Context context)185     private static Set<ComponentName> getInstalledServices(Context context) {
186         final Set<ComponentName> installedServices = new HashSet<>();
187         installedServices.clear();
188 
189         final List<AccessibilityServiceInfo> installedServiceInfos =
190                 AccessibilityManager.getInstance(context)
191                         .getInstalledAccessibilityServiceList();
192         if (installedServiceInfos == null) {
193             return installedServices;
194         }
195 
196         for (final AccessibilityServiceInfo info : installedServiceInfos) {
197             final ResolveInfo resolveInfo = info.getResolveInfo();
198             final ComponentName installedService = new ComponentName(
199                     resolveInfo.serviceInfo.packageName,
200                     resolveInfo.serviceInfo.name);
201             installedServices.add(installedService);
202         }
203         return installedServices;
204     }
205 
206 }
207