diff --git a/src/com/android/settings/network/ActiveSubsciptionsListener.java b/src/com/android/settings/network/ActiveSubsciptionsListener.java
new file mode 100644
index 0000000..3e4272d
--- /dev/null
+++ b/src/com/android/settings/network/ActiveSubsciptionsListener.java
@@ -0,0 +1,320 @@
+/*
+ * Copyright (C) 2019 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.settings.network;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.os.Handler;
+import android.os.Looper;
+import android.telephony.CarrierConfigManager;
+import android.telephony.SubscriptionInfo;
+import android.telephony.SubscriptionManager;
+import android.telephony.TelephonyManager;
+import android.text.TextUtils;
+import android.util.Log;
+
+import androidx.annotation.VisibleForTesting;
+
+import com.android.internal.telephony.TelephonyIntents;
+
+import java.util.List;
+import java.util.concurrent.atomic.AtomicInteger;
+
+/**
+ * A listener for active subscription change
+ */
+public abstract class ActiveSubsciptionsListener
+        extends SubscriptionManager.OnSubscriptionsChangedListener
+        implements AutoCloseable {
+
+    private static final String TAG = "ActiveSubsciptions";
+    private static final boolean DEBUG = false;
+
+    /**
+     * Constructor
+     *
+     * @param looper {@code Looper} of this listener
+     * @param context {@code Context} of this listener
+     */
+    public ActiveSubsciptionsListener(Looper looper, Context context) {
+        mLooper = looper;
+        mContext = context;
+
+        mCacheState = new AtomicInteger(STATE_NOT_LISTENING);
+        mMaxActiveSubscriptionInfos = new AtomicInteger(MAX_SUBSCRIPTION_UNKNOWN);
+
+        mSubscriptionChangeIntentFilter = new IntentFilter();
+        mSubscriptionChangeIntentFilter.addAction(
+                CarrierConfigManager.ACTION_CARRIER_CONFIG_CHANGED);
+        mSubscriptionChangeIntentFilter.addAction(
+                TelephonyIntents.ACTION_RADIO_TECHNOLOGY_CHANGED);
+        mSubscriptionChangeIntentFilter.addAction(
+                TelephonyManager.ACTION_MULTI_SIM_CONFIG_CHANGED);
+    }
+
+    @VisibleForTesting
+    BroadcastReceiver getSubscriptionChangeReceiver() {
+        return new BroadcastReceiver() {
+            @Override
+            public void onReceive(Context context, Intent intent) {
+                if (isInitialStickyBroadcast()) {
+                    return;
+                }
+                final String action = intent.getAction();
+                if (TextUtils.isEmpty(action)) {
+                    return;
+                }
+                if (CarrierConfigManager.ACTION_CARRIER_CONFIG_CHANGED.equals(action)) {
+                    final int subId = intent.getIntExtra(
+                            CarrierConfigManager.EXTRA_SUBSCRIPTION_INDEX,
+                            SubscriptionManager.INVALID_SUBSCRIPTION_ID);
+                    if (!clearCachedSubId(subId)) {
+                        return;
+                    }
+                }
+                onSubscriptionsChanged();
+            }
+        };
+    }
+
+    private Looper mLooper;
+    private Context mContext;
+
+    private static final int STATE_NOT_LISTENING = 0;
+    private static final int STATE_STOPPING      = 1;
+    private static final int STATE_PREPARING     = 2;
+    private static final int STATE_LISTENING     = 3;
+    private static final int STATE_DATA_CACHED   = 4;
+
+    private AtomicInteger mCacheState;
+    private SubscriptionManager mSubscriptionManager;
+
+    private IntentFilter mSubscriptionChangeIntentFilter;
+    private BroadcastReceiver mSubscriptionChangeReceiver;
+
+    private static final int MAX_SUBSCRIPTION_UNKNOWN = -1;
+
+    private AtomicInteger mMaxActiveSubscriptionInfos;
+    private List<SubscriptionInfo> mCachedActiveSubscriptionInfo;
+
+    /**
+     * Active subscriptions got changed
+     */
+    public abstract void onChanged();
+
+    @Override
+    public void onSubscriptionsChanged() {
+        // clear value in cache
+        clearCache();
+        listenerNotify();
+    }
+
+    /**
+     * Start listening subscriptions change
+     */
+    public void start() {
+        monitorSubscriptionsChange(true);
+    }
+
+    /**
+     * Stop listening subscriptions change
+     */
+    public void stop() {
+        monitorSubscriptionsChange(false);
+    }
+
+    /**
+     * Implementation of {@code AutoCloseable}
+     */
+    public void close() {
+        stop();
+    }
+
+    /**
+     * Get SubscriptionManager
+     *
+     * @return a SubscriptionManager
+     */
+    public SubscriptionManager getSubscriptionManager() {
+        if (mSubscriptionManager == null) {
+            mSubscriptionManager = mContext.getSystemService(SubscriptionManager.class);
+        }
+        return mSubscriptionManager;
+    }
+
+    /**
+     * Get current max. number active subscription info(s) been setup within device
+     *
+     * @return max. number of active subscription info(s)
+     */
+    public int getActiveSubscriptionInfoCountMax() {
+        int cacheState = mCacheState.get();
+        if (cacheState < STATE_LISTENING) {
+            return getSubscriptionManager().getActiveSubscriptionInfoCountMax();
+        }
+
+        mMaxActiveSubscriptionInfos.compareAndSet(MAX_SUBSCRIPTION_UNKNOWN,
+                getSubscriptionManager().getActiveSubscriptionInfoCountMax());
+        return mMaxActiveSubscriptionInfos.get();
+    }
+
+    /**
+     * Get a list of active subscription info
+     *
+     * @return A list of active subscription info
+     */
+    public List<SubscriptionInfo> getActiveSubscriptionsInfo() {
+        if (mCacheState.get() >= STATE_DATA_CACHED) {
+            return mCachedActiveSubscriptionInfo;
+        }
+        mCachedActiveSubscriptionInfo = getSubscriptionManager().getActiveSubscriptionInfoList();
+        mCacheState.compareAndSet(STATE_LISTENING, STATE_DATA_CACHED);
+
+        if (DEBUG) {
+            if ((mCachedActiveSubscriptionInfo == null)
+                    || (mCachedActiveSubscriptionInfo.size() <= 0)) {
+                Log.d(TAG, "active subscriptions: " + mCachedActiveSubscriptionInfo);
+            } else {
+                final StringBuilder logString = new StringBuilder("active subscriptions:");
+                for (SubscriptionInfo subInfo : mCachedActiveSubscriptionInfo) {
+                    logString.append(" " + subInfo.getSubscriptionId());
+                }
+                Log.d(TAG, logString.toString());
+            }
+        }
+
+        return mCachedActiveSubscriptionInfo;
+    }
+
+    /**
+     * Get an active subscription info with given subscription ID
+     *
+     * @param subId target subscription ID
+     * @return A subscription info which is active list
+     */
+    public SubscriptionInfo getActiveSubscriptionInfo(int subId) {
+        final List<SubscriptionInfo> subInfoList = getActiveSubscriptionsInfo();
+        if (subInfoList == null) {
+            return null;
+        }
+        for (SubscriptionInfo subInfo : subInfoList) {
+            if (subInfo.getSubscriptionId() == subId) {
+                return subInfo;
+            }
+        }
+        return null;
+    }
+
+    /**
+     * Get a list of all subscription info which accessible by Settings app
+     *
+     * @return A list of accessible subscription info
+     */
+    public List<SubscriptionInfo> getAccessibleSubscriptionsInfo() {
+        return getSubscriptionManager().getAvailableSubscriptionInfoList();
+    }
+
+    /**
+     * Get an accessible subscription info with given subscription ID
+     *
+     * @param subId target subscription ID
+     * @return A subscription info which is accessible list
+     */
+    public SubscriptionInfo getAccessibleSubscriptionInfo(int subId) {
+        // Always check if subId is part of activeSubscriptions
+        // since there's cache design within SubscriptionManager.
+        // That give us a chance to avoid from querying ContentProvider.
+        final SubscriptionInfo activeSubInfo = getActiveSubscriptionInfo(subId);
+        if (activeSubInfo != null) {
+            return activeSubInfo;
+        }
+
+        final List<SubscriptionInfo> subInfoList = getAccessibleSubscriptionsInfo();
+        if (subInfoList == null) {
+            return null;
+        }
+        for (SubscriptionInfo subInfo : subInfoList) {
+            if (subInfo.getSubscriptionId() == subId) {
+                return subInfo;
+            }
+        }
+        return null;
+    }
+
+    /**
+     * Clear data cached within listener
+     */
+    public void clearCache() {
+        mMaxActiveSubscriptionInfos.set(MAX_SUBSCRIPTION_UNKNOWN);
+        mCacheState.compareAndSet(STATE_DATA_CACHED, STATE_LISTENING);
+        mCachedActiveSubscriptionInfo = null;
+    }
+
+    private void monitorSubscriptionsChange(boolean on) {
+        if (on) {
+            if (!mCacheState.compareAndSet(STATE_NOT_LISTENING, STATE_PREPARING)) {
+                return;
+            }
+
+            if (mSubscriptionChangeReceiver == null) {
+                mSubscriptionChangeReceiver = getSubscriptionChangeReceiver();
+            }
+            mContext.registerReceiver(mSubscriptionChangeReceiver,
+                    mSubscriptionChangeIntentFilter, null, new Handler(mLooper));
+            getSubscriptionManager().addOnSubscriptionsChangedListener(this);
+            mCacheState.compareAndSet(STATE_PREPARING, STATE_LISTENING);
+            return;
+        }
+
+        final int currentState = mCacheState.getAndSet(STATE_STOPPING);
+        if (currentState <= STATE_STOPPING) {
+            mCacheState.compareAndSet(STATE_STOPPING, currentState);
+            return;
+        }
+        if (mSubscriptionChangeReceiver != null) {
+            mContext.unregisterReceiver(mSubscriptionChangeReceiver);
+        }
+        getSubscriptionManager().removeOnSubscriptionsChangedListener(this);
+        clearCache();
+        mCacheState.compareAndSet(STATE_STOPPING, STATE_NOT_LISTENING);
+    }
+
+    private void listenerNotify() {
+        if (mCacheState.get() < STATE_LISTENING) {
+            return;
+        }
+        onChanged();
+    }
+
+    private boolean clearCachedSubId(int subId) {
+        if (mCacheState.get() < STATE_DATA_CACHED) {
+            return false;
+        }
+        if (mCachedActiveSubscriptionInfo == null) {
+            return false;
+        }
+        for (SubscriptionInfo subInfo : mCachedActiveSubscriptionInfo) {
+            if (subInfo.getSubscriptionId() == subId) {
+                clearCache();
+                return true;
+            }
+        }
+        return false;
+    }
+}
diff --git a/src/com/android/settings/network/GlobalSettingsChangeListener.java b/src/com/android/settings/network/GlobalSettingsChangeListener.java
new file mode 100644
index 0000000..4c58c60
--- /dev/null
+++ b/src/com/android/settings/network/GlobalSettingsChangeListener.java
@@ -0,0 +1,136 @@
+/*
+ * Copyright (C) 2019 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.settings.network;
+
+import static androidx.lifecycle.Lifecycle.Event.ON_DESTROY;
+import static androidx.lifecycle.Lifecycle.Event.ON_START;
+import static androidx.lifecycle.Lifecycle.Event.ON_STOP;
+
+import android.content.Context;
+import android.database.ContentObserver;
+import android.net.Uri;
+import android.os.Handler;
+import android.os.Looper;
+import android.provider.Settings;
+
+import androidx.lifecycle.Lifecycle;
+import androidx.lifecycle.LifecycleObserver;
+import androidx.lifecycle.OnLifecycleEvent;
+
+import java.util.concurrent.atomic.AtomicBoolean;
+
+/**
+ * A listener for Settings.Global configuration change, with support of Lifecycle
+ */
+public abstract class GlobalSettingsChangeListener extends ContentObserver
+        implements LifecycleObserver, AutoCloseable {
+
+    /**
+     * Constructor
+     *
+     * @param context {@code Context} of this listener
+     * @param field field of Global Settings
+     */
+    public GlobalSettingsChangeListener(Context context, String field) {
+        this(Looper.getMainLooper(), context, field);
+    }
+
+    /**
+     * Constructor
+     *
+     * @param looper {@code Looper} for processing callback
+     * @param context {@code Context} of this listener
+     * @param field field of Global Settings
+     */
+    public GlobalSettingsChangeListener(Looper looper, Context context, String field) {
+        super(new Handler(looper));
+        mContext = context;
+        mField = field;
+        mUri = Settings.Global.getUriFor(field);
+        mListening = new AtomicBoolean(false);
+        monitorUri(true);
+    }
+
+    private Context mContext;
+    private String mField;
+    private Uri mUri;
+    private AtomicBoolean mListening;
+    private Lifecycle mLifecycle;
+
+    /**
+     * Observed Settings got changed
+     */
+    public abstract void onChanged(String field);
+
+    /**
+     * Notify change of Globals.Setting based on given Lifecycle
+     *
+     * @param lifecycle life cycle to reference
+     */
+    public void notifyChangeBasedOn(Lifecycle lifecycle) {
+        if (mLifecycle != null) {
+            mLifecycle.removeObserver(this);
+        }
+        if (lifecycle != null) {
+            lifecycle.addObserver(this);
+        }
+        mLifecycle = lifecycle;
+    }
+
+    public void onChange(boolean selfChange) {
+        if (!mListening.get()) {
+            return;
+        }
+        onChanged(mField);
+    }
+
+    @OnLifecycleEvent(ON_START)
+    void onStart() {
+        monitorUri(true);
+    }
+
+    @OnLifecycleEvent(ON_STOP)
+    void onStop() {
+        monitorUri(false);
+    }
+
+    @OnLifecycleEvent(ON_DESTROY)
+    void onDestroy() {
+        close();
+    }
+
+    /**
+     * Implementation of AutoCloseable
+     */
+    public void close() {
+        monitorUri(false);
+        notifyChangeBasedOn(null);
+    }
+
+    private void monitorUri(boolean on) {
+        if (!mListening.compareAndSet(!on, on)) {
+            return;
+        }
+
+        if (on) {
+            mContext.getContentResolver().registerContentObserver(mUri, false, this);
+            return;
+        }
+
+        mContext.getContentResolver().unregisterContentObserver(this);
+    }
+}
diff --git a/src/com/android/settings/network/ProxySubscriptionManager.java b/src/com/android/settings/network/ProxySubscriptionManager.java
new file mode 100644
index 0000000..b10c727
--- /dev/null
+++ b/src/com/android/settings/network/ProxySubscriptionManager.java
@@ -0,0 +1,237 @@
+/*
+ * Copyright (C) 2019 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.settings.network;
+
+import static androidx.lifecycle.Lifecycle.Event.ON_DESTROY;
+import static androidx.lifecycle.Lifecycle.Event.ON_START;
+import static androidx.lifecycle.Lifecycle.Event.ON_STOP;
+
+import android.content.Context;
+import android.os.Looper;
+import android.provider.Settings;
+import android.telephony.SubscriptionInfo;
+import android.telephony.SubscriptionManager;
+
+import androidx.lifecycle.Lifecycle;
+import androidx.lifecycle.LifecycleObserver;
+import androidx.lifecycle.OnLifecycleEvent;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * A proxy to the subscription manager
+ */
+public class ProxySubscriptionManager implements LifecycleObserver {
+
+    /**
+     * Interface for monitor active subscriptions list changing
+     */
+    public interface OnActiveSubscriptionChangedListener {
+        /**
+         * When active subscriptions list get changed
+         */
+        void onChanged();
+        /**
+         * get Lifecycle of listener
+         *
+         * @return Returns Lifecycle.
+         */
+        default Lifecycle getLifecycle() {
+            return null;
+        }
+    }
+
+    /**
+     * Get proxy instance to subscription manager
+     *
+     * @return proxy to subscription manager
+     */
+    public static ProxySubscriptionManager getInstance(Context context) {
+        if (sSingleton != null) {
+            return sSingleton;
+        }
+        sSingleton = new ProxySubscriptionManager(context.getApplicationContext());
+        return sSingleton;
+    }
+
+    private static ProxySubscriptionManager sSingleton;
+
+    private ProxySubscriptionManager(Context context) {
+        final Looper looper = Looper.getMainLooper();
+
+        mActiveSubscriptionsListeners =
+                new ArrayList<OnActiveSubscriptionChangedListener>();
+
+        mSubsciptionsMonitor = new ActiveSubsciptionsListener(looper, context) {
+            public void onChanged() {
+                notifyAllListeners();
+            }
+        };
+        mAirplaneModeMonitor = new GlobalSettingsChangeListener(looper,
+                context, Settings.Global.AIRPLANE_MODE_ON) {
+            public void onChanged(String field) {
+                mSubsciptionsMonitor.clearCache();
+                notifyAllListeners();
+            }
+        };
+
+        mSubsciptionsMonitor.start();
+    }
+
+    private Lifecycle mLifecycle;
+    private ActiveSubsciptionsListener mSubsciptionsMonitor;
+    private GlobalSettingsChangeListener mAirplaneModeMonitor;
+
+    private List<OnActiveSubscriptionChangedListener> mActiveSubscriptionsListeners;
+
+    private void notifyAllListeners() {
+        for (OnActiveSubscriptionChangedListener listener : mActiveSubscriptionsListeners) {
+            final Lifecycle lifecycle = listener.getLifecycle();
+            if ((lifecycle == null)
+                    || (lifecycle.getCurrentState().isAtLeast(Lifecycle.State.STARTED))) {
+                listener.onChanged();
+            }
+        }
+    }
+
+    /**
+     * Lifecycle for data within proxy
+     *
+     * @param lifecycle life cycle to reference
+     */
+    public void setLifecycle(Lifecycle lifecycle) {
+        if (mLifecycle == lifecycle) {
+            return;
+        }
+        if (mLifecycle != null) {
+            mLifecycle.removeObserver(this);
+        }
+        if (lifecycle != null) {
+            lifecycle.addObserver(this);
+        }
+        mLifecycle = lifecycle;
+        mAirplaneModeMonitor.notifyChangeBasedOn(lifecycle);
+    }
+
+    @OnLifecycleEvent(ON_START)
+    void onStart() {
+        mSubsciptionsMonitor.start();
+    }
+
+    @OnLifecycleEvent(ON_STOP)
+    void onStop() {
+        mSubsciptionsMonitor.stop();
+    }
+
+    @OnLifecycleEvent(ON_DESTROY)
+    void onDestroy() {
+        mSubsciptionsMonitor.close();
+        mAirplaneModeMonitor.close();
+
+        if (mLifecycle != null) {
+            mLifecycle.removeObserver(this);
+            mLifecycle = null;
+
+            sSingleton = null;
+        }
+    }
+
+    /**
+     * Get SubscriptionManager
+     *
+     * @return a SubscriptionManager
+     */
+    public SubscriptionManager get() {
+        return mSubsciptionsMonitor.getSubscriptionManager();
+    }
+
+    /**
+     * Get current max. number active subscription info(s) been setup within device
+     *
+     * @return max. number of active subscription info(s)
+     */
+    public int getActiveSubscriptionInfoCountMax() {
+        return mSubsciptionsMonitor.getActiveSubscriptionInfoCountMax();
+    }
+
+    /**
+     * Get a list of active subscription info
+     *
+     * @return A list of active subscription info
+     */
+    public List<SubscriptionInfo> getActiveSubscriptionsInfo() {
+        return mSubsciptionsMonitor.getActiveSubscriptionsInfo();
+    }
+
+    /**
+     * Get an active subscription info with given subscription ID
+     *
+     * @param subId target subscription ID
+     * @return A subscription info which is active list
+     */
+    public SubscriptionInfo getActiveSubscriptionInfo(int subId) {
+        return mSubsciptionsMonitor.getActiveSubscriptionInfo(subId);
+    }
+
+    /**
+     * Get a list of accessible subscription info
+     *
+     * @return A list of accessible subscription info
+     */
+    public List<SubscriptionInfo> getAccessibleSubscriptionsInfo() {
+        return mSubsciptionsMonitor.getAccessibleSubscriptionsInfo();
+    }
+
+    /**
+     * Get an accessible subscription info with given subscription ID
+     *
+     * @param subId target subscription ID
+     * @return A subscription info which is accessible list
+     */
+    public SubscriptionInfo getAccessibleSubscriptionInfo(int subId) {
+        return mSubsciptionsMonitor.getAccessibleSubscriptionInfo(subId);
+    }
+
+    /**
+     * Clear data cached within proxy
+     */
+    public void clearCache() {
+        mSubsciptionsMonitor.clearCache();
+    }
+
+    /**
+     * Add listener to active subscriptions monitor list
+     *
+     * @param listener listener to active subscriptions change
+     */
+    public void addActiveSubscriptionsListener(OnActiveSubscriptionChangedListener listener) {
+        if (mActiveSubscriptionsListeners.contains(listener)) {
+            return;
+        }
+        mActiveSubscriptionsListeners.add(listener);
+    }
+
+    /**
+     * Remove listener from active subscriptions monitor list
+     *
+     * @param listener listener to active subscriptions change
+     */
+    public void removeActiveSubscriptionsListener(OnActiveSubscriptionChangedListener listener) {
+        mActiveSubscriptionsListeners.remove(listener);
+    }
+}
diff --git a/tests/robotests/src/com/android/settings/network/ActiveSubsciptionsListenerTest.java b/tests/robotests/src/com/android/settings/network/ActiveSubsciptionsListenerTest.java
new file mode 100644
index 0000000..4c7b55b
--- /dev/null
+++ b/tests/robotests/src/com/android/settings/network/ActiveSubsciptionsListenerTest.java
@@ -0,0 +1,200 @@
+/*
+ * Copyright (C) 2019 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.settings.network;
+
+import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.spy;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.robolectric.Shadows.shadowOf;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.os.Looper;
+import android.telephony.CarrierConfigManager;
+import android.telephony.SubscriptionInfo;
+import android.telephony.SubscriptionManager;
+import android.telephony.TelephonyManager;
+
+import androidx.test.ext.junit.runners.AndroidJUnit4;
+
+import com.android.internal.telephony.TelephonyIntents;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.MockitoAnnotations;
+import org.robolectric.RuntimeEnvironment;
+import org.robolectric.shadow.api.Shadow;
+import org.robolectric.shadows.ShadowBroadcastReceiver;
+import org.robolectric.shadows.ShadowContextImpl;
+import org.robolectric.shadows.ShadowSubscriptionManager;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+@RunWith(AndroidJUnit4.class)
+public class ActiveSubsciptionsListenerTest {
+    private static final int SUB_ID1 = 3;
+    private static final int SUB_ID2 = 7;
+
+    private static final Intent INTENT_RADIO_TECHNOLOGY_CHANGED =
+            new Intent(TelephonyIntents.ACTION_RADIO_TECHNOLOGY_CHANGED);
+
+    private static final Intent INTENT_MULTI_SIM_CONFIG_CHANGED =
+            new Intent(TelephonyManager.ACTION_MULTI_SIM_CONFIG_CHANGED);
+
+    private static final Intent INTENT_CARRIER_CONFIG_CHANGED =
+            new Intent(CarrierConfigManager.ACTION_CARRIER_CONFIG_CHANGED);
+
+    private Context mContext;
+    private ShadowContextImpl mShadowContextImpl;
+    private SubscriptionManager mSubscriptionManager;
+    private ShadowSubscriptionManager mShadowSubscriptionManager;
+    private List<SubscriptionInfo> mActiveSubscriptions;
+
+    private ActiveSubsciptionsListenerImpl mListener;
+    private BroadcastReceiver mReceiver;
+    private ShadowBroadcastReceiver mShadowReceiver;
+
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+
+        mContext = RuntimeEnvironment.application.getBaseContext();
+        mShadowContextImpl = Shadow.extract(mContext);
+
+        mSubscriptionManager = spy(mContext.getSystemService(SubscriptionManager.class));
+        mShadowSubscriptionManager = shadowOf(mSubscriptionManager);
+
+        mActiveSubscriptions = new ArrayList<SubscriptionInfo>();
+        mActiveSubscriptions.add(ShadowSubscriptionManager.SubscriptionInfoBuilder
+                .newBuilder().setId(SUB_ID1).buildSubscriptionInfo());
+        mActiveSubscriptions.add(ShadowSubscriptionManager.SubscriptionInfoBuilder
+                .newBuilder().setId(SUB_ID2).buildSubscriptionInfo());
+        mShadowSubscriptionManager.setActiveSubscriptionInfoList(mActiveSubscriptions);
+
+        mListener = spy(new ActiveSubsciptionsListenerImpl(Looper.getMainLooper(), mContext));
+        doReturn(mSubscriptionManager).when(mListener).getSubscriptionManager();
+        mReceiver = mListener.getSubscriptionChangeReceiver();
+        mShadowReceiver = shadowOf(mReceiver);
+        doReturn(mReceiver).when(mListener).getSubscriptionChangeReceiver();
+    }
+
+    @After
+    public void cleanUp() {
+        mListener.close();
+    }
+
+    private class ActiveSubsciptionsListenerImpl extends ActiveSubsciptionsListener {
+        private ActiveSubsciptionsListenerImpl(Looper looper, Context context) {
+            super(looper, context);
+        }
+        public void onChanged() {}
+    }
+
+    private void sendIntentToReceiver(Intent intent) {
+        mShadowReceiver.onReceive(mContext, intent, new AtomicBoolean(false));
+    }
+
+    @Test
+    public void constructor_noListeningWasSetup() {
+        verify(mListener, never()).onChanged();
+    }
+
+    @Test
+    public void start_configChangedIntent_onChangedShouldBeCalled() {
+        sendIntentToReceiver(INTENT_RADIO_TECHNOLOGY_CHANGED);
+        sendIntentToReceiver(INTENT_MULTI_SIM_CONFIG_CHANGED);
+        verify(mListener, never()).onChanged();
+
+        mListener.start();
+
+        sendIntentToReceiver(INTENT_RADIO_TECHNOLOGY_CHANGED);
+        verify(mListener, times(1)).onChanged();
+
+        sendIntentToReceiver(INTENT_MULTI_SIM_CONFIG_CHANGED);
+        verify(mListener, times(2)).onChanged();
+
+        mListener.stop();
+
+        sendIntentToReceiver(INTENT_RADIO_TECHNOLOGY_CHANGED);
+        sendIntentToReceiver(INTENT_MULTI_SIM_CONFIG_CHANGED);
+        verify(mListener, times(2)).onChanged();
+    }
+
+    @Test
+    public void start_carrierConfigChangedIntent_onChangedWhenSubIdBeenCached() {
+        sendIntentToReceiver(INTENT_CARRIER_CONFIG_CHANGED);
+        verify(mListener, never()).onChanged();
+
+        mListener.start();
+
+        mListener.getActiveSubscriptionsInfo();
+
+        sendIntentToReceiver(INTENT_CARRIER_CONFIG_CHANGED);
+        verify(mListener, never()).onChanged();
+
+        INTENT_CARRIER_CONFIG_CHANGED.putExtra(CarrierConfigManager.EXTRA_SUBSCRIPTION_INDEX,
+                SUB_ID2);
+        sendIntentToReceiver(INTENT_CARRIER_CONFIG_CHANGED);
+        verify(mListener, times(1)).onChanged();
+
+        mListener.stop();
+
+        sendIntentToReceiver(INTENT_CARRIER_CONFIG_CHANGED);
+        verify(mListener, times(1)).onChanged();
+    }
+
+
+    @Test
+    public void start_alwaysFetchAndCacheResult() {
+        mListener.start();
+
+        List<SubscriptionInfo> subInfoList = null;
+        int numberOfAccess = 0;
+        for (int numberOfSubInfo = mActiveSubscriptions.size(); numberOfSubInfo >= 0;
+                numberOfSubInfo--) {
+            if (mActiveSubscriptions.size() > numberOfSubInfo) {
+                mActiveSubscriptions.remove(numberOfSubInfo);
+            }
+            mShadowSubscriptionManager.setActiveSubscriptionInfoList(mActiveSubscriptions);
+
+            // fetch twice and test if they generated access to SubscriptionManager only once
+            subInfoList = mListener.getActiveSubscriptionsInfo();
+            subInfoList = mListener.getActiveSubscriptionsInfo();
+
+            numberOfAccess++;
+            verify(mSubscriptionManager, times(numberOfAccess)).getActiveSubscriptionInfoList();
+
+            mListener.clearCache();
+        }
+
+        mShadowSubscriptionManager.setActiveSubscriptionInfoList(null);
+
+        // fetch twice and test if they generated access to SubscriptionManager only once
+        subInfoList = mListener.getActiveSubscriptionsInfo();
+        subInfoList = mListener.getActiveSubscriptionsInfo();
+
+        numberOfAccess++;
+        verify(mSubscriptionManager, times(numberOfAccess)).getActiveSubscriptionInfoList();
+    }
+}
diff --git a/tests/robotests/src/com/android/settings/network/GlobalSettingsChangeListenerTest.java b/tests/robotests/src/com/android/settings/network/GlobalSettingsChangeListenerTest.java
new file mode 100644
index 0000000..e419071
--- /dev/null
+++ b/tests/robotests/src/com/android/settings/network/GlobalSettingsChangeListenerTest.java
@@ -0,0 +1,86 @@
+/*
+ * Copyright (C) 2019 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.settings.network;
+
+import static org.mockito.Mockito.doNothing;
+import static org.mockito.Mockito.spy;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+
+import android.content.Context;
+import android.os.Looper;
+import android.provider.Settings;
+
+import androidx.lifecycle.Lifecycle;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.robolectric.RobolectricTestRunner;
+import org.robolectric.RuntimeEnvironment;
+
+@RunWith(RobolectricTestRunner.class)
+public class GlobalSettingsChangeListenerTest {
+
+    @Mock
+    private Lifecycle mLifecycle;
+
+    private Context mContext;
+    private GlobalSettingsChangeListener mListener;
+
+    private static final String SETTINGS_FIELD = Settings.Global.AIRPLANE_MODE_ON;
+
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+        mContext = spy(RuntimeEnvironment.application);
+        mListener = spy(new GlobalSettingsChangeListener(Looper.getMainLooper(),
+                mContext, SETTINGS_FIELD) {
+            public void onChanged(String field) {}
+        });
+
+        doNothing().when(mLifecycle).addObserver(mListener);
+        doNothing().when(mLifecycle).removeObserver(mListener);
+    }
+
+    @Test
+    public void whenChanged_onChangedBeenCalled() {
+        mListener.onChange(false);
+        verify(mListener, times(1)).onChanged(SETTINGS_FIELD);
+    }
+
+    @Test
+    public void whenNotifyChangeBasedOnLifecycle_onStopEvent_onChangedNotCalled() {
+        mListener.notifyChangeBasedOn(mLifecycle);
+        mListener.onStart();
+
+        mListener.onChange(false);
+        verify(mListener, times(1)).onChanged(SETTINGS_FIELD);
+
+        mListener.onStop();
+
+        mListener.onChange(false);
+        verify(mListener, times(1)).onChanged(SETTINGS_FIELD);
+
+        mListener.onStart();
+
+        mListener.onChange(false);
+        verify(mListener, times(2)).onChanged(SETTINGS_FIELD);
+    }
+}