Android - Domains 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 seconds the list gets updated in case of changes

android/app/src/main/java/io/highfidelity/hifiinterface/fragment/HomeFragment.java

@@ -76,19 +76,23 @@ public class HomeFragment extends Fragment {
         });
         mDomainAdapter.setListener(new DomainAdapter.AdapterListener() {
             @Override
-            public void onEmptyAdapter() {
+            public void onEmptyAdapter(boolean shouldStopRefreshing) {
                 searchNoResultsView.setText(R.string.search_no_results);
                 searchNoResultsView.setVisibility(View.VISIBLE);
                 mDomainsView.setVisibility(View.GONE);
+                if (shouldStopRefreshing) {
                     mSwipeRefreshLayout.setRefreshing(false);
                 }
+            }
 
             @Override
-            public void onNonEmptyAdapter() {
+            public void onNonEmptyAdapter(boolean shouldStopRefreshing) {
                 searchNoResultsView.setVisibility(View.GONE);
                 mDomainsView.setVisibility(View.VISIBLE);
+                if (shouldStopRefreshing) {
                     mSwipeRefreshLayout.setRefreshing(false);
                 }
+            }
 
             @Override
             public void onError(Exception e, String message) {
@@ -96,11 +100,20 @@ public class HomeFragment extends Fragment {
             }
         });
         mDomainsView.setAdapter(mDomainAdapter);
+        mDomainAdapter.startLoad();
 
         mSearchView = rootView.findViewById(R.id.searchView);
         mSearchIconView = rootView.findViewById(R.id.search_mag_icon);
         mClearSearch = rootView.findViewById(R.id.search_clear);
 
+        getActivity().getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN);
+
+        return rootView;
+    }
+
+    @Override
+    public void onStart() {
+        super.onStart();
         mSearchView.addTextChangedListener(new TextWatcher() {
             @Override
             public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {}
@@ -142,10 +155,6 @@ public class HomeFragment extends Fragment {
                 mDomainAdapter.loadDomains(mSearchView.getText().toString(), true);
             }
         });
-
-        getActivity().getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN);
-
-        return rootView;
     }
 
     @Override

android/app/src/main/java/io/highfidelity/hifiinterface/view/DomainAdapter.java

@@ -12,6 +12,7 @@ import android.widget.TextView;
 
 import com.squareup.picasso.Picasso;
 
+import java.util.Arrays;
 import java.util.List;
 
 import io.highfidelity.hifiinterface.R;
@@ -36,19 +37,39 @@ public class DomainAdapter extends RecyclerView.Adapter<DomainAdapter.ViewHolder
     // references to our domains
     private Domain[] mDomains = {};
 
+    private static Domain[] DOMAINS_TMP_CACHE = {};
+
     public DomainAdapter(Context c, String protocol, String lastLocation) {
         mContext = c;
         this.mInflater = LayoutInflater.from(mContext);
         mProtocol = protocol;
         mLastLocation = lastLocation;
         domainProvider = new UserStoryDomainProvider(mProtocol);
-        loadDomains("", true);
     }
 
     public void setListener(AdapterListener adapterListener) {
         mAdapterListener = adapterListener;
     }
 
+    public void startLoad() {
+        useTmpCachedDomains();
+        loadDomains("", true);
+    }
+
+    private void useTmpCachedDomains() {
+        if (DOMAINS_TMP_CACHE != null && DOMAINS_TMP_CACHE.length > 0) {
+            mDomains = Arrays.copyOf(DOMAINS_TMP_CACHE, DOMAINS_TMP_CACHE.length);
+            notifyDataSetChanged();
+            if (mAdapterListener != null) {
+                if (mDomains.length == 0) {
+                    mAdapterListener.onEmptyAdapter(false);
+                } else {
+                    mAdapterListener.onNonEmptyAdapter(false);
+                }
+            }
+        }
+    }
+
     public void loadDomains(String filterText, boolean forceRefresh) {
         domainProvider.retrieve(filterText, new DomainProvider.DomainCallback() {
             @Override
@@ -60,13 +81,16 @@ public class DomainAdapter extends RecyclerView.Adapter<DomainAdapter.ViewHolder
                 overrideDefaultThumbnails(domain);
 
                 mDomains = new Domain[domain.size()];
-                mDomains = domain.toArray(mDomains);
+                domain.toArray(mDomains);
+                if (filterText.isEmpty()) {
+                    DOMAINS_TMP_CACHE = Arrays.copyOf(mDomains, mDomains.length);
+                }
                 notifyDataSetChanged();
                 if (mAdapterListener != null) {
                     if (mDomains.length == 0) {
-                        mAdapterListener.onEmptyAdapter();
+                        mAdapterListener.onEmptyAdapter(true);
                     } else {
-                        mAdapterListener.onNonEmptyAdapter();
+                        mAdapterListener.onNonEmptyAdapter(true);
                     }
                 }
             }
@@ -112,8 +136,6 @@ public class DomainAdapter extends RecyclerView.Adapter<DomainAdapter.ViewHolder
 
     @Override
     public void onBindViewHolder(ViewHolder holder, int position) {
-        // TODO
-        //holder.thumbnail.setImageResource(mDomains[position].thumbnail);
         Domain domain = mDomains[position];
         holder.mDomainName.setText(domain.name);
         Uri uri = Uri.parse(domain.thumbnail);
@@ -164,8 +186,8 @@ public class DomainAdapter extends RecyclerView.Adapter<DomainAdapter.ViewHolder
     }
 
     public interface AdapterListener {
-        void onEmptyAdapter();
+        void onEmptyAdapter(boolean shouldStopRefreshing);
-        void onNonEmptyAdapter();
+        void onNonEmptyAdapter(boolean shouldStopRefreshing);
         void onError(Exception e, String message);
     }
 }