1 /*
2  * Copyright (C) 2016 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 package com.android.documentsui.prefs;
17 
18 import android.content.Context;
19 import android.content.SharedPreferences;
20 import android.preference.PreferenceManager;
21 import android.text.TextUtils;
22 
23 import com.android.documentsui.R;
24 
25 /**
26  * Provides an interface (and runtime implementation) for preferences that are
27  * scoped (presumably to an activity). This eliminates the need to pass
28  * scoping values into {@link LocalPreferences}, as well as eliminates
29  * the static-coupling to {@link LocalPreferences} increasing testability.
30  */
31 public interface ScopedPreferences {
32 
33     static final String INCLUDE_DEVICE_ROOT = "includeDeviceRoot";
34     static final String ENABLE_ARCHIVE_CREATION = "enableArchiveCreation-";
35 
getShowDeviceRoot()36     boolean getShowDeviceRoot();
setShowDeviceRoot(boolean display)37     void setShowDeviceRoot(boolean display);
38 
39     /**
40      * @param scope An arbitrary string representitive of the scope
41      *        for prefs that are set using this object.
42      */
create(Context context, String scope)43     public static ScopedPreferences create(Context context, String scope) {
44         return new RuntimeScopedPreferences(context,
45                 PreferenceManager.getDefaultSharedPreferences(context), scope);
46     }
47 
48     static final class RuntimeScopedPreferences implements ScopedPreferences {
49 
50         private final SharedPreferences mSharedPrefs;
51         private final String mScope;
52         private final boolean mDefaultShowDeviceRoot;
53 
RuntimeScopedPreferences(Context context, SharedPreferences sharedPrefs, String scope)54         private RuntimeScopedPreferences(Context context, SharedPreferences sharedPrefs,
55                 String scope)  {
56             assert(!TextUtils.isEmpty(scope));
57 
58             mSharedPrefs = sharedPrefs;
59             mScope = scope;
60             mDefaultShowDeviceRoot = context.getResources()
61                     .getBoolean(R.bool.config_default_show_device_root);
62         }
63 
64         @Override
getShowDeviceRoot()65         public boolean getShowDeviceRoot() {
66             return mSharedPrefs.getBoolean(INCLUDE_DEVICE_ROOT, mDefaultShowDeviceRoot);
67         }
68 
69         @Override
setShowDeviceRoot(boolean display)70         public void setShowDeviceRoot(boolean display) {
71             mSharedPrefs.edit().putBoolean(INCLUDE_DEVICE_ROOT, display).apply();
72         }
73     }
74 
shouldBackup(String s)75     static boolean shouldBackup(String s) {
76         return INCLUDE_DEVICE_ROOT.equals(s);
77     }
78 }
79