src/com/android/documentsui/base/ScopedPreferences.java

/*
 * Copyright (C) 2016 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.android.documentsui.base;

import android.content.Context;
import android.content.SharedPreferences;
import android.preference.PreferenceManager;

public interface ScopedPreferences {

    boolean getShowDeviceRoot();
    void setShowDeviceRoot(boolean display);

    public static ScopedPreferences create(Context context, String scope) {
        return new RuntimeScopedPreferences(
                PreferenceManager.getDefaultSharedPreferences(context), scope);
    }

    static final class RuntimeScopedPreferences implements ScopedPreferences {

        private static final String INCLUDE_DEVICE_ROOT = "includeDeviceRoot-";

        private SharedPreferences mSharedPrefs;
        private String mScope;

        private RuntimeScopedPreferences(SharedPreferences sharedPrefs, String scope)  {
            mSharedPrefs = sharedPrefs;
            mScope = scope;
        }

        @Override
        public boolean getShowDeviceRoot() {
            return mSharedPrefs.getBoolean(INCLUDE_DEVICE_ROOT + mScope, false);
        }

        @Override
        public void setShowDeviceRoot(boolean display) {
            mSharedPrefs.edit().putBoolean(INCLUDE_DEVICE_ROOT + mScope, display).apply();
        }
    }
}