add BroadcastReceiver to listen to changes in battery save mode and r…

…eload the activity if received

app/src/main/java/com/amaze/filemanager/ui/activities/superclasses/ThemedActivity.java

@@ -21,6 +21,7 @@
 package com.amaze.filemanager.ui.activities.superclasses;
 
 import static android.os.Build.VERSION.SDK_INT;
+import static android.os.Build.VERSION_CODES.LOLLIPOP;
 import static com.amaze.filemanager.ui.fragments.preferencefragments.PreferencesConstants.PREFERENCE_COLORED_NAVIGATION;
 
 import com.amaze.filemanager.R;
@@ -34,10 +35,15 @@
 import com.readystatesoftware.systembartint.SystemBarTintManager;
 
 import android.app.ActivityManager;
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
 import android.content.res.Configuration;
 import android.graphics.drawable.BitmapDrawable;
 import android.os.Build;
 import android.os.Bundle;
+import android.os.PowerManager;
 import android.view.View;
 import android.view.ViewGroup;
 import android.view.Window;
@@ -53,11 +59,20 @@
 /** Created by arpitkh996 on 03-03-2016. */
 public class ThemedActivity extends PreferenceActivity {
   private int uiModeNight = -1;
+  private final BroadcastReceiver powerModeReceiver =
+      new BroadcastReceiver() {
+        @Override
+        public void onReceive(Context context, Intent i) {
+          recreate();
+        }
+      };
 
   @Override
   public void onCreate(Bundle savedInstanceState) {
     super.onCreate(savedInstanceState);
 
+    registerPowerModeReceiver();
+
     // setting window background color instead of each item, in order to reduce pixel overdraw
     if (getAppTheme().equals(AppTheme.LIGHT)) {
       getWindow().setBackgroundDrawableResource(android.R.color.white);
@@ -309,4 +324,24 @@ protected void onResume() {
     uiModeNight = getResources().getConfiguration().uiMode & Configuration.UI_MODE_NIGHT_MASK;
     setTheme();
   }
+
+  @Override
+  protected void onDestroy() {
+    super.onDestroy();
+
+    unregisterPowerModeReceiver();
+  }
+
+  private void registerPowerModeReceiver() {
+    if (SDK_INT >= LOLLIPOP) {
+      registerReceiver(
+          powerModeReceiver, new IntentFilter(PowerManager.ACTION_POWER_SAVE_MODE_CHANGED));
+    }
+  }
+
+  private void unregisterPowerModeReceiver() {
+    if (SDK_INT >= LOLLIPOP) {
+      unregisterReceiver(powerModeReceiver);
+    }
+  }
 }