Italian translation, loading indicator and empty list message

app/src/main/java/it/danieleverducci/subitobeers/ui/BeersFragment.kt

@@ -32,7 +32,7 @@ class BeersFragment : Fragment(), BeersRepository.Listener, BeerRecyclerAdapter.
 
     private val rvAdapter = BeerRecyclerAdapter()
     private val repo = BeersRepository()
-    private var binding: FragmentBeersListBinding? = null
+    private lateinit var binding: FragmentBeersListBinding
 
     override fun onCreateView(
         inflater: LayoutInflater, container: ViewGroup?,
@@ -40,7 +40,7 @@ class BeersFragment : Fragment(), BeersRepository.Listener, BeerRecyclerAdapter.
     ): View? {
         setHasOptionsMenu(true);
 
-        if (binding == null) {
+        if (!this::binding.isInitialized) {
             // Inflate layout
             binding = FragmentBeersListBinding.inflate(
                 LayoutInflater.from(container!!.context),
@@ -49,12 +49,12 @@ class BeersFragment : Fragment(), BeersRepository.Listener, BeerRecyclerAdapter.
             )
 
             // Register filter buttons listeners
-            binding!!.listFilterSinceBt.setOnClickListener { onFilterButtonClicked(FILTERTYPE.SINCE) }
+            binding.listFilterSinceBt.setOnClickListener { onFilterButtonClicked(FILTERTYPE.SINCE) }
-            binding!!.listFilterToBt.setOnClickListener { onFilterButtonClicked(FILTERTYPE.TO) }
+            binding.listFilterToBt.setOnClickListener { onFilterButtonClicked(FILTERTYPE.TO) }
-            binding!!.listFilterClear.setOnClickListener { onFilterButtonClicked(FILTERTYPE.CLEAR) }
+            binding.listFilterClear.setOnClickListener { onFilterButtonClicked(FILTERTYPE.CLEAR) }
 
             // Set the adapter
-            with(binding!!.list) {
+            with(binding.list) {
                 layoutManager = LinearLayoutManager(context)
                 adapter = rvAdapter
             }
@@ -68,18 +68,18 @@ class BeersFragment : Fragment(), BeersRepository.Listener, BeerRecyclerAdapter.
             // Restore state
             repo.filter.brewedBefore = savedInstanceState?.getString(INSTANCESTATE_FILTER_TO)
             repo.filter.brewedAfter = savedInstanceState?.getString(INSTANCESTATE_FILTER_SINCE)
-            binding!!.listFilterDropdown.visibility =
+            binding.listFilterDropdown.visibility =
                 if (savedInstanceState?.getBoolean(INSTANCESTATE_FILTER_OPEN) == true) View.VISIBLE else View.GONE
 
             // Load first page
             loadBeers(true)
         }
 
-        return binding!!.root
+        return binding.root
     }
 
     override fun onSaveInstanceState(outState: Bundle) {
-        outState.putBoolean(INSTANCESTATE_FILTER_OPEN, binding!!.listFilterDropdown.visibility == View.VISIBLE)
+        outState.putBoolean(INSTANCESTATE_FILTER_OPEN, binding.listFilterDropdown.visibility == View.VISIBLE)
         outState.putString(INSTANCESTATE_FILTER_SINCE, repo.filter.brewedAfter)
         outState.putString(INSTANCESTATE_FILTER_TO, repo.filter.brewedBefore)
         super.onSaveInstanceState(outState)
@@ -97,10 +97,22 @@ class BeersFragment : Fragment(), BeersRepository.Listener, BeerRecyclerAdapter.
         return super.onOptionsItemSelected(item)
     }
 
+    /**
+     * Beers obtained from services callback
+     * @param beers List of beers
+     * @param more Whether there are more beers to retrieve
+     */
     override fun onBeersObtained(beers: List<Beer>, more: Boolean) {
+        binding.listProgress.visibility = View.GONE
         rvAdapter.addItems(beers, more)
+
+        binding.listEmpty.visibility =
+            if (beers.isEmpty() && repo.page == 1) View.VISIBLE else View.GONE
     }
 
+    /**
+     * Unable to obtain beers from services
+     */
     override fun onFailure() {
         Toast.makeText(context, R.string.network_error, Toast.LENGTH_SHORT).show()
     }
@@ -123,8 +135,8 @@ class BeersFragment : Fragment(), BeersRepository.Listener, BeerRecyclerAdapter.
         if (type == FILTERTYPE.CLEAR) {
             repo.filter.clear()
             loadBeers(true)
-            binding!!.listFilterSinceBt.setText(R.string.list_filter_brewed_after)
+            binding.listFilterSinceBt.setText(R.string.list_filter_brewed_after)
-            binding!!.listFilterToBt.setText(R.string.list_filter_brewed_before)
+            binding.listFilterToBt.setText(R.string.list_filter_brewed_before)
             return
         }
 
@@ -133,10 +145,10 @@ class BeersFragment : Fragment(), BeersRepository.Listener, BeerRecyclerAdapter.
 
             if (type == FILTERTYPE.SINCE) {
                 repo.filter.setBrewedAfter(selMonth, selYear)
-                binding!!.listFilterSinceBt.setText(repo.filter.brewedAfter)
+                binding.listFilterSinceBt.setText(repo.filter.brewedAfter)
             } else {
                 repo.filter.setBrewedBefore(selMonth, selYear)
-                binding!!.listFilterToBt.setText(repo.filter.brewedBefore)
+                binding.listFilterToBt.setText(repo.filter.brewedBefore)
             }
 
             // Update list
@@ -168,8 +180,8 @@ class BeersFragment : Fragment(), BeersRepository.Listener, BeerRecyclerAdapter.
      * Toggles beer filter visibility
      */
     private fun toggleFilter() {
-        binding!!.listFilterDropdown.visibility =
+        binding.listFilterDropdown.visibility =
-            if (binding!!.listFilterDropdown.visibility == View.VISIBLE) View.GONE else View.VISIBLE
+            if (binding.listFilterDropdown.visibility == View.VISIBLE) View.GONE else View.VISIBLE
     }
 
     /**
@@ -178,6 +190,7 @@ class BeersFragment : Fragment(), BeersRepository.Listener, BeerRecyclerAdapter.
      */
     private fun loadBeers(clear: Boolean) {
         if (clear) {
+            binding.listProgress.visibility = View.VISIBLE
             rvAdapter.clear()
             repo.reset()
         }

app/src/main/res/layout/fragment_beers_list.xml

@@ -49,6 +49,22 @@
 
     </LinearLayout>
 
+    <ProgressBar
+        android:id="@+id/list_progress"
+        android:layout_width="match_parent"
+        android:layout_height="50dp"
+        android:layout_marginTop="100dp"
+        android:indeterminate="true"
+        android:visibility="gone"/>
+
+    <TextView
+        android:id="@+id/list_empty"
+        android:layout_width="match_parent"
+        android:layout_height="200dp"
+        android:gravity="center"
+        android:text="@string/list_empty"
+        android:visibility="gone"/>
+
     <androidx.recyclerview.widget.RecyclerView
         android:id="@+id/list"
         android:name="it.danieleverducci.subitobeers.BeersFragment"

app/src/main/res/values-it/strings.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string name="app_name">SubitoBeers</string>
+
+    <!-- Beers list -->
+    <string name="network_error">Impossibile ottenere le birre</string>
+    <string name="list_filter_brewed_after">Prod. dopo</string>
+    <string name="list_filter_brewed_before">Prod. prima</string>
+    <string name="list_empty">Nessuna birra trovata</string>
+
+    <!-- Beers detail -->
+
+    <!-- Generic placeholders -->
+    <string name="placeholder_beertitle">Nome della birra</string>
+    <string name="placeholder_tagline">Lorem ipsum dolor sit amet</string>
+    <string name="placeholder_firstbrewed">00/0000</string>
+    <string name="placeholder_description">Lorem ipsum dolor sit amet, consectetur adipiscing elit. In tristique consectetur felis vel pretium. Praesent tincidunt vestibulum lacus, molestie rhoncus lacus fermentum vel. Morbi vel pulvinar sapien, sed ultrices arcu. Vivamus gravida nulla vel ex varius, vel consequat dolor tincidunt. Fusce maximus quis mi eget tristique. Aenean sed facilisis libero. Aliquam volutpat posuere fringilla. Praesent in lorem at elit ornare congue et quis quam. Maecenas tempus et purus ac rhoncus. Donec in pulvinar ex. Aliquam ac vehicula dolor. Nam vitae tortor id nibh congue sollicitudin id in nisi. Proin lorem eros, congue at euismod et, malesuada porta nunc. Proin laoreet massa ac mi lacinia, eget tincidunt odio vestibulum. Vestibulum fermentum nunc nunc, eget ultrices nisi tempor non. Curabitur lorem leo, fringilla et pellentesque a, pharetra id magna. </string>
+
+    <!-- Menu -->
+    <string name="action_filter">Filtra</string>
+</resources>

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

@@ -5,6 +5,7 @@
     <string name="network_error">Unable to retrieve beers from network</string>
     <string name="list_filter_brewed_after">Brewed after</string>
     <string name="list_filter_brewed_before">Brewed before</string>
+    <string name="list_empty">No beers found</string>
 
     <!-- Beers detail -->