From ed965babdf72afd5e07dc3c3af579b07040c7c9c Mon Sep 17 00:00:00 2001
From: Cristian Luis Duarte <cristian.duarte.mb@gmail.com>
Date: Tue, 21 Aug 2018 17:47:40 -0300
Subject: [PATCH] Android - People List - cache in memory only on this instance
 (deleted if app restarts) allows for fast list display. Showing again also
 asks for update so in some ms the list gets updated in case of changes

---
 .../fragment/FriendsFragment.java             | 14 +++++---
 .../hifiinterface/view/UserListAdapter.java   | 35 ++++++++++++++++---
 2 files changed, 40 insertions(+), 9 deletions(-)

diff --git a/android/app/src/main/java/io/highfidelity/hifiinterface/fragment/FriendsFragment.java b/android/app/src/main/java/io/highfidelity/hifiinterface/fragment/FriendsFragment.java
index 2a008d7950..2475c4d887 100644
--- a/android/app/src/main/java/io/highfidelity/hifiinterface/fragment/FriendsFragment.java
+++ b/android/app/src/main/java/io/highfidelity/hifiinterface/fragment/FriendsFragment.java
@@ -98,13 +98,17 @@ public class FriendsFragment extends Fragment {
 
         mUsersAdapter.setListener(new UserListAdapter.AdapterListener() {
             @Override
-            public void onEmptyAdapter() {
-                mSwipeRefreshLayout.setRefreshing(false);
+            public void onEmptyAdapter(boolean shouldStopRefreshing) {
+                if (shouldStopRefreshing) {
+                    mSwipeRefreshLayout.setRefreshing(false);
+                }
             }
 
             @Override
-            public void onNonEmptyAdapter() {
-                mSwipeRefreshLayout.setRefreshing(false);
+            public void onNonEmptyAdapter(boolean shouldStopRefreshing) {
+                if (shouldStopRefreshing) {
+                    mSwipeRefreshLayout.setRefreshing(false);
+                }
             }
 
             @Override
@@ -115,6 +119,8 @@ public class FriendsFragment extends Fragment {
 
         mUsersView.setAdapter(mUsersAdapter);
 
+        mUsersAdapter.startLoad();
+
         mSlidingUpPanelLayout.setFadeOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View view) {
diff --git a/android/app/src/main/java/io/highfidelity/hifiinterface/view/UserListAdapter.java b/android/app/src/main/java/io/highfidelity/hifiinterface/view/UserListAdapter.java
index 9f62b21250..a34de5b34e 100644
--- a/android/app/src/main/java/io/highfidelity/hifiinterface/view/UserListAdapter.java
+++ b/android/app/src/main/java/io/highfidelity/hifiinterface/view/UserListAdapter.java
@@ -37,28 +37,53 @@ public class UserListAdapter extends RecyclerView.Adapter<UserListAdapter.ViewHo
     private ItemClickListener mClickListener;
     private AdapterListener mAdapterListener;
 
+    private static List<User> USERS_TMP_CACHE;
+
     public UserListAdapter(Context c, UsersProvider usersProvider) {
         mContext = c;
         mInflater = LayoutInflater.from(mContext);
         mProvider = usersProvider;
-        loadUsers();
     }
 
     public void setListener(AdapterListener adapterListener) {
         mAdapterListener = adapterListener;
     }
 
+    public void startLoad() {
+        useTmpCachedUsers();
+        loadUsers();
+    }
+
+    private void useTmpCachedUsers() {
+        if (USERS_TMP_CACHE != null && USERS_TMP_CACHE.size() > 0) {
+            mUsers = new ArrayList<>(USERS_TMP_CACHE.size());
+            mUsers.addAll(USERS_TMP_CACHE);
+            notifyDataSetChanged();
+            if (mAdapterListener != null) {
+                if (mUsers.isEmpty()) {
+                    mAdapterListener.onEmptyAdapter(false);
+                } else {
+                    mAdapterListener.onNonEmptyAdapter(false);
+                }
+            }
+        }
+    }
+
     public void loadUsers() {
         mProvider.retrieve(new UsersProvider.UsersCallback() {
             @Override
             public void retrieveOk(List<User> users) {
                 mUsers = new ArrayList<>(users);
                 notifyDataSetChanged();
+
+                USERS_TMP_CACHE = new ArrayList<>(mUsers.size());
+                USERS_TMP_CACHE.addAll(mUsers);
+
                 if (mAdapterListener != null) {
                     if (mUsers.isEmpty()) {
-                        mAdapterListener.onEmptyAdapter();
+                        mAdapterListener.onEmptyAdapter(true);
                     } else {
-                        mAdapterListener.onNonEmptyAdapter();
+                        mAdapterListener.onNonEmptyAdapter(true);
                     }
                 }
             }
@@ -240,8 +265,8 @@ public class UserListAdapter extends RecyclerView.Adapter<UserListAdapter.ViewHo
     }
 
     public interface AdapterListener {
-        void onEmptyAdapter();
-        void onNonEmptyAdapter();
+        void onEmptyAdapter(boolean shouldStopRefreshing);
+        void onNonEmptyAdapter(boolean shouldStopRefreshing);
         void onError(Exception e, String message);
     }
 }