Preserve dark theme settings

app/src/main/java/app/insti/Constants.java

@@ -6,6 +6,7 @@ public class Constants {
     public static final int MY_PERMISSIONS_REQUEST_LOCATION = 3;
     public static final int RESULT_LOAD_IMAGE = 11;
     public static final int REQUEST_CAMERA_INT_ID = 101;
+    public static final String DARK_THEME = "dark_theme";
     public static final String NOTIFICATIONS_RESPONSE_JSON = "notifications_json";
     public static final String EVENT_ID = "event_id";
     public static final String EVENT_LATITUDE = "event_latitude";

app/src/main/java/app/insti/activity/MainActivity.java

@@ -7,6 +7,7 @@ import android.app.NotificationChannel;
 import android.app.NotificationManager;
 import android.content.Context;
 import android.content.Intent;
+import android.content.SharedPreferences;
 import android.content.pm.PackageInfo;
 import android.content.pm.PackageManager;
 import android.graphics.Color;
@@ -115,6 +116,11 @@ public class MainActivity extends AppCompatActivity implements NavigationView.On
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
 
+        /* Check for dark theme */
+        SharedPreferences sharedPref = getSharedPreferences(Constants.PREF_NAME, Context.MODE_PRIVATE);
+        if(sharedPref.getBoolean(Constants.DARK_THEME, false))
+            this.setTheme(R.style.AppThemeDark);
+
         ServiceGenerator serviceGenerator = new ServiceGenerator(getApplicationContext());
         Utils.setRetrofitInterface(serviceGenerator.getRetrofitInterface());
 

app/src/main/java/app/insti/fragment/SettingsFragment.java

 package app.insti.fragment;
 
+import android.content.Context;
 import android.content.Intent;
+import android.content.SharedPreferences;
 import android.net.Uri;
 import android.os.Bundle;
 import android.support.v7.preference.Preference;
@@ -22,17 +24,23 @@ import retrofit2.Callback;
 import retrofit2.Response;
 
 public class SettingsFragment extends PreferenceFragmentCompat {
-    SwitchPreferenceCompat showContactPref;
-    SwitchPreferenceCompat darkThemePref;
-    Preference profilePref;
-    Preference feedbackPref;
-    Preference aboutPref;
-    Preference logoutPref;
+    private SwitchPreferenceCompat showContactPref;
+    private SwitchPreferenceCompat darkThemePref;
+    private Preference profilePref;
+    private Preference feedbackPref;
+    private Preference aboutPref;
+    private Preference logoutPref;
+    private SharedPreferences sharedPref;
+    private SharedPreferences.Editor editor;
 
     @Override
     public void onCreatePreferences(Bundle savedInstanceState, String rootKey) {
         setPreferencesFromResource(R.xml.preferences, rootKey);
 
+        // Get preferences and editor
+        sharedPref = getActivity().getSharedPreferences(Constants.PREF_NAME, Context.MODE_PRIVATE);
+        editor = sharedPref.edit();
+
         // Show contact number
         showContactPref = (SwitchPreferenceCompat) findPreference("show_contact");
         showContactPref.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
@@ -53,6 +61,7 @@ public class SettingsFragment extends PreferenceFragmentCompat {
                 return true;
             }
         });
+        darkThemePref.setChecked(sharedPref.getBoolean(Constants.DARK_THEME, false));
 
         // Update Profile
         profilePref = findPreference("profile");
@@ -164,6 +173,8 @@ public class SettingsFragment extends PreferenceFragmentCompat {
     }
 
     public void toggleDarkTheme(final SwitchPreferenceCompat showContactPref, Object o) {
+        editor.putBoolean(Constants.DARK_THEME, (boolean) o);
+        editor.commit();
         Utils.changeTheme(this, (boolean) o);
     }
 

app/src/main/res/values/styles.xml

@@ -10,6 +10,8 @@
         <item name="themeColorInverse">#000000</item>
         <item name="newsColor">#F2F2F2</item>
         <item name="urlColor">@color/colorPrimary</item>
+        <item name="windowActionBar">false</item>
+        <item name="windowNoTitle">true</item>
     </style>
 
     <style name="AppTheme.NoActionBar">
@@ -25,6 +27,8 @@
         <item name="themeColorInverse">#FFFFFF</item>
         <item name="newsColor">#00000000</item>
         <item name="urlColor">@color/colorAccent</item>
+        <item name="windowActionBar">false</item>
+        <item name="windowNoTitle">true</item>
     </style>
 
     <style name="AppThemeDark.NoActionBar">