From 01ad0c8c9148ca1f6fac8bba6d0ffc17807c72eb Mon Sep 17 00:00:00 2001
From: knightshade <abhishekpoonia22@gmail.com>
Date: Mon, 26 Feb 2018 00:34:35 +0530
Subject: [PATCH] Notifications list retained across orientation change. Fixes
 #1198

---
 app/build.gradle                              |  4 +--
 .../notification/NotificationActivity.java    | 36 +++++++++++++------
 .../NotificationWorkerFragment.java           | 29 +++++++++++++++
 3 files changed, 57 insertions(+), 12 deletions(-)
 create mode 100644 app/src/main/java/fr/free/nrw/commons/notification/NotificationWorkerFragment.java

diff --git a/app/build.gradle b/app/build.gradle
index c021e28ac..6f225dc2f 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -49,7 +49,7 @@ dependencies {
     compile 'com.facebook.stetho:stetho:1.5.0'
 
     testCompile 'junit:junit:4.12'
-    testCompile 'org.robolectric:robolectric:3.4'
+    testCompile 'org.robolectric:robolectric:3.7.1'
 
     testCompile 'com.squareup.okhttp3:mockwebserver:3.8.1'
     androidTestCompile 'com.squareup.okhttp3:mockwebserver:3.8.1'
@@ -78,7 +78,7 @@ dependencies {
     androidTestImplementation "org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version"
 
     testImplementation 'junit:junit:4.12'
-    testImplementation 'org.robolectric:robolectric:3.4'
+    testImplementation 'org.robolectric:robolectric:3.7.1'
     testImplementation 'org.mockito:mockito-all:1.10.19'
 
     testImplementation 'com.squareup.okhttp3:mockwebserver:3.8.1'
diff --git a/app/src/main/java/fr/free/nrw/commons/notification/NotificationActivity.java b/app/src/main/java/fr/free/nrw/commons/notification/NotificationActivity.java
index 4b4ca3007..da9b60ba8 100644
--- a/app/src/main/java/fr/free/nrw/commons/notification/NotificationActivity.java
+++ b/app/src/main/java/fr/free/nrw/commons/notification/NotificationActivity.java
@@ -1,6 +1,7 @@
 package fr.free.nrw.commons.notification;
 
 import android.annotation.SuppressLint;
+import android.app.FragmentManager;
 import android.content.Context;
 import android.content.Intent;
 import android.net.Uri;
@@ -10,7 +11,6 @@ import android.support.v7.widget.RecyclerView;
 
 import com.pedrogomez.renderers.RVRendererAdapter;
 
-import java.util.Collections;
 import java.util.List;
 
 import javax.inject.Inject;
@@ -35,12 +35,16 @@ public class NotificationActivity extends NavigationBaseActivity {
 
     @Inject NotificationController controller;
 
+    private static final String TAG_NOTIFICATION_WORKER_FRAGMENT = "NotificationWorkerFragment";
+    private NotificationWorkerFragment mNotificationWorkerFragment;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_notification);
         ButterKnife.bind(this);
+        mNotificationWorkerFragment = (NotificationWorkerFragment) getFragmentManager()
+                                      .findFragmentByTag(TAG_NOTIFICATION_WORKER_FRAGMENT);
         initListView();
         initDrawer();
     }
@@ -55,14 +59,18 @@ public class NotificationActivity extends NavigationBaseActivity {
     private void addNotifications() {
         Timber.d("Add notifications");
 
-        Observable.fromCallable(() -> controller.getNotifications())
-                .subscribeOn(Schedulers.io())
-                .observeOn(AndroidSchedulers.mainThread())
-                .subscribe(notificationList -> {
-                    Collections.reverse(notificationList);
-                    Timber.d("Number of notifications is %d", notificationList.size());
-                    setAdapter(notificationList);
-                }, throwable -> Timber.e(throwable, "Error occurred while loading notifications"));
+        if(mNotificationWorkerFragment == null){
+            Observable.fromCallable(() -> controller.getNotifications())
+                    .subscribeOn(Schedulers.io())
+                    .observeOn(AndroidSchedulers.mainThread())
+                    .subscribe(notificationList -> {
+                        Timber.d("Number of notifications is %d", notificationList.size());
+                        initializeAndSetNotificationList(notificationList);
+                        setAdapter(notificationList);
+                    }, throwable -> Timber.e(throwable, "Error occurred while loading notifications"));
+        } else {
+            setAdapter(mNotificationWorkerFragment.getNotificationList());
+        }
     }
 
     private void handleUrl(String url) {
@@ -85,4 +93,12 @@ public class NotificationActivity extends NavigationBaseActivity {
         Intent intent = new Intent(context, NotificationActivity.class);
         context.startActivity(intent);
     }
-}
+
+    private void initializeAndSetNotificationList(List<Notification> notificationList){
+        FragmentManager fm = getFragmentManager();
+        mNotificationWorkerFragment = new NotificationWorkerFragment();
+        fm.beginTransaction().add(mNotificationWorkerFragment, TAG_NOTIFICATION_WORKER_FRAGMENT)
+                .commit();
+        mNotificationWorkerFragment.setNotificationList(notificationList);
+    }
+}
\ No newline at end of file
diff --git a/app/src/main/java/fr/free/nrw/commons/notification/NotificationWorkerFragment.java b/app/src/main/java/fr/free/nrw/commons/notification/NotificationWorkerFragment.java
new file mode 100644
index 000000000..bb85fc696
--- /dev/null
+++ b/app/src/main/java/fr/free/nrw/commons/notification/NotificationWorkerFragment.java
@@ -0,0 +1,29 @@
+package fr.free.nrw.commons.notification;
+
+import android.app.Fragment;
+import android.os.Bundle;
+import android.support.annotation.Nullable;
+
+import java.util.List;
+
+/**
+ * Created by knightshade on 25/2/18.
+ */
+
+public class NotificationWorkerFragment extends Fragment {
+    private List<Notification> notificationList;
+
+    @Override
+    public void onCreate(@Nullable Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setRetainInstance(true);
+    }
+
+    public void setNotificationList(List<Notification> notificationList){
+        this.notificationList = notificationList;
+    }
+
+    public List<Notification> getNotificationList(){
+        return notificationList;
+    }
+}