feat: add search functionality for songs within playlists

app/src/main/java/com/cappielloantonio/tempo/ui/adapter/SongHorizontalAdapter.java

@@ -4,6 +4,8 @@ import android.os.Bundle;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
+import android.widget.Filter;
+import android.widget.Filterable;
 
 import androidx.annotation.NonNull;
 import androidx.appcompat.content.res.AppCompatResources;
@@ -29,19 +31,54 @@ import java.util.Objects;
 import java.util.Optional;
 
 @UnstableApi
-public class SongHorizontalAdapter extends RecyclerView.Adapter<SongHorizontalAdapter.ViewHolder> {
+public class SongHorizontalAdapter extends RecyclerView.Adapter<SongHorizontalAdapter.ViewHolder> implements Filterable {
     private final ClickCallback click;
     private final boolean showCoverArt;
     private final boolean showAlbum;
     private final AlbumID3 album;
 
+    private List<Child> songsFull;
     private List<Child> songs;
+    private String currentFilter;
+
+    private final Filter filtering = new Filter() {
+        @Override
+        protected FilterResults performFiltering(CharSequence constraint) {
+            List<Child> filteredList = new ArrayList<>();
+
+            if (constraint == null || constraint.length() == 0) {
+                filteredList.addAll(songsFull);
+            } else {
+                String filterPattern = constraint.toString().toLowerCase().trim();
+                currentFilter = filterPattern;
+
+                for (Child item : songsFull) {
+                    if (item.getTitle().toLowerCase().contains(filterPattern)) {
+                        filteredList.add(item);
+                    }
+                }
+            }
+
+            FilterResults results = new FilterResults();
+            results.values = filteredList;
+
+            return results;
+        }
+
+        @Override
+        protected void publishResults(CharSequence constraint, FilterResults results) {
+            songs = (List<Child>) results.values;
+            notifyDataSetChanged();
+        }
+    };
 
     public SongHorizontalAdapter(ClickCallback click, boolean showCoverArt, boolean showAlbum, AlbumID3 album) {
         this.click = click;
         this.showCoverArt = showCoverArt;
         this.showAlbum = showAlbum;
         this.songs = Collections.emptyList();
+        this.songsFull = Collections.emptyList();
+        this.currentFilter = "";
         this.album = album;
     }
 
@@ -135,7 +172,8 @@ public class SongHorizontalAdapter extends RecyclerView.Adapter<SongHorizontalAd
     }
 
     public void setItems(List<Child> songs) {
-        this.songs = songs != null ? songs : Collections.emptyList();
+        this.songsFull = songs != null ? songs : Collections.emptyList();
+        filtering.filter(currentFilter);
         notifyDataSetChanged();
     }
 
@@ -149,6 +187,11 @@ public class SongHorizontalAdapter extends RecyclerView.Adapter<SongHorizontalAd
         return position;
     }
 
+    @Override
+    public Filter getFilter() {
+        return filtering;
+    }
+
     public Child getItem(int id) {
         return songs.get(id);
     }

app/src/main/java/com/cappielloantonio/tempo/ui/fragment/PlaylistPageFragment.java

@@ -1,6 +1,7 @@
 package com.cappielloantonio.tempo.ui.fragment;
 
 import android.content.ComponentName;
+import android.content.Context;
 import android.os.Bundle;
 import android.view.LayoutInflater;
 import android.view.Menu;
@@ -8,6 +9,9 @@ import android.view.MenuInflater;
 import android.view.MenuItem;
 import android.view.View;
 import android.view.ViewGroup;
+import android.view.inputmethod.EditorInfo;
+import android.view.inputmethod.InputMethodManager;
+import android.widget.SearchView;
 
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
@@ -58,8 +62,28 @@ public class PlaylistPageFragment extends Fragment implements ClickCallback {
 
     @Override
     public void onCreateOptionsMenu(@NonNull Menu menu, @NonNull MenuInflater inflater) {
-        super.onCreateOptionsMenu(menu, inflater);
         inflater.inflate(R.menu.playlist_page_menu, menu);
+
+        MenuItem searchItem = menu.findItem(R.id.action_search);
+
+        SearchView searchView = (SearchView) searchItem.getActionView();
+        searchView.setImeOptions(EditorInfo.IME_ACTION_DONE);
+        searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
+            @Override
+            public boolean onQueryTextSubmit(String query) {
+                searchView.clearFocus();
+                return false;
+            }
+
+            @Override
+            public boolean onQueryTextChange(String newText) {
+                songHorizontalAdapter.getFilter().filter(newText);
+                return false;
+            }
+        });
+
+        searchView.setPadding(-32, 0, 0, 0);
+
         initMenuOption(menu);
     }
 
@@ -152,11 +176,19 @@ public class PlaylistPageFragment extends Fragment implements ClickCallback {
         bind.playlistSongCountLabel.setText(getString(R.string.playlist_song_count, playlistPageViewModel.getPlaylist().getSongCount()));
         bind.playlistDurationLabel.setText(getString(R.string.playlist_duration, MusicUtil.getReadableDurationString(playlistPageViewModel.getPlaylist().getDuration(), false)));
 
-        bind.animToolbar.setNavigationOnClickListener(v -> activity.navController.navigateUp());
+        bind.animToolbar.setNavigationOnClickListener(v -> {
+            hideKeyboard(v);
+            activity.navController.navigateUp();
+        });
 
         Objects.requireNonNull(bind.animToolbar.getOverflowIcon()).setTint(requireContext().getResources().getColor(R.color.titleTextColor, null));
     }
 
+    private void hideKeyboard(View view) {
+        InputMethodManager imm = (InputMethodManager) requireActivity().getSystemService(Context.INPUT_METHOD_SERVICE);
+        imm.hideSoftInputFromWindow(view.getWindowToken(), 0);
+    }
+
     private void initMusicButton() {
         playlistPageViewModel.getPlaylistSongLiveList().observe(getViewLifecycleOwner(), songs -> {
             if (bind != null) {

app/src/main/res/menu/playlist_page_menu.xml

@@ -1,6 +1,13 @@
 <?xml version="1.0" encoding="utf-8"?>
 <menu xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto">
+    <item
+        android:id="@+id/action_search"
+        android:icon="@drawable/ic_search"
+        android:title="@string/menu_search_button"
+        app:actionViewClass="android.widget.SearchView"
+        app:showAsAction="ifRoom" />
+
     <item
         android:id="@+id/action_download_playlist"
         android:icon="@drawable/ic_file_download"

app/src/main/res/menu/toolbar_menu.xml

@@ -8,5 +8,4 @@
         android:title="@string/menu_search_button"
         app:actionViewClass="android.widget.SearchView"
         app:showAsAction="ifRoom" />
-
 </menu>