Create BatterySaverReceiver

Cherry-picked from oc-dev

This cl elicits BatterySaverReceiver that listen to the change about
battery state and battery saver state.

BatterySaverController and BatterySaverSettings will use this receiver
to update the UI.

Bug: 32410757
Test: RunSettingsRoboTests
Change-Id: Ia92c6776985b89fe6a8d5b8d80898e502942b9b5

src/com/android/settings/fuelgauge/BatterySaverReceiver.java

@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2017 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.fuelgauge;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.os.BatteryManager;
+import android.os.PowerManager;
+import android.util.Log;
+
+public class BatterySaverReceiver extends BroadcastReceiver {
+    private static final String TAG = "BatterySaverReceiver";
+    private static final boolean DEBUG = false;
+    private boolean mRegistered;
+    private Context mContext;
+    private BatterySaverListener mBatterySaverListener;
+
+    public BatterySaverReceiver(Context context) {
+        mContext = context;
+    }
+
+    @Override
+    public void onReceive(Context context, Intent intent) {
+        if (DEBUG) Log.d(TAG, "Received " + intent.getAction());
+        String action = intent.getAction();
+        if (PowerManager.ACTION_POWER_SAVE_MODE_CHANGING.equals(action)) {
+            if (mBatterySaverListener != null) {
+                mBatterySaverListener.onPowerSaveModeChanged();
+            }
+        } else if (Intent.ACTION_BATTERY_CHANGED.equals(action)) {
+            // disable BSM switch if phone is plugged in
+            if (mBatterySaverListener != null) {
+                final boolean pluggedIn = intent.getIntExtra(BatteryManager.EXTRA_PLUGGED, 0) != 0;
+                mBatterySaverListener.onBatteryChanged(pluggedIn);
+            }
+        }
+    }
+
+    public void setListening(boolean listening) {
+        if (listening && !mRegistered) {
+            final IntentFilter ifilter = new IntentFilter();
+            ifilter.addAction(PowerManager.ACTION_POWER_SAVE_MODE_CHANGING);
+            ifilter.addAction(Intent.ACTION_BATTERY_CHANGED);
+            mContext.registerReceiver(this, ifilter);
+            mRegistered = true;
+        } else if (!listening && mRegistered) {
+            mContext.unregisterReceiver(this);
+            mRegistered = false;
+        }
+    }
+
+    public void setBatterySaverListener(BatterySaverListener lsn) {
+        mBatterySaverListener = lsn;
+    }
+
+    interface BatterySaverListener {
+        void onPowerSaveModeChanged();
+        void onBatteryChanged(boolean pluggedIn);
+    }
+}