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.server.textservices;
18 
19 import android.annotation.NonNull;
20 import android.annotation.Nullable;
21 import android.annotation.UserIdInt;
22 import android.view.textservice.SpellCheckerInfo;
23 
24 import com.android.server.LocalServices;
25 
26 /**
27  * Local interface of {@link TextServicesManagerService} inside system server process.
28  */
29 public abstract class TextServicesManagerInternal {
30     /**
31      * Returns the list of installed input methods for the specified user.
32      *
33      * <p>CAVEAT: This method is not fully implemented yet. This may return an empty list if
34      * {@code userId} for a background user is specified. Check the implementation before starting
35      * this method.</p>
36      *
37      * @param userId The user ID to be queried.
38      * @return {@link SpellCheckerInfo} that is currently selected {@code userId}.
39      */
40     @Nullable
getCurrentSpellCheckerForUser(@serIdInt int userId)41     public abstract SpellCheckerInfo getCurrentSpellCheckerForUser(@UserIdInt int userId);
42 
43     /**
44      * Fake implementation of {@link TextServicesManagerInternal}.  All the methods do nothing.
45      */
46     private static final TextServicesManagerInternal NOP =
47             new TextServicesManagerInternal() {
48                 @Override
49                 public SpellCheckerInfo getCurrentSpellCheckerForUser(@UserIdInt int userId) {
50                     return null;
51                 }
52             };
53 
54     /**
55      * @return Global instance if exists.  Otherwise, a dummy no-op instance.
56      */
57     @NonNull
get()58     public static TextServicesManagerInternal get() {
59         final TextServicesManagerInternal instance =
60                 LocalServices.getService(TextServicesManagerInternal.class);
61         return instance != null ? instance : NOP;
62     }
63 }
64