Added support for the section popup

app/build.gradle

@@ -137,5 +137,5 @@ dependencies {
     compile 'de.psdev.licensesdialog:licensesdialog:1.8.0'
     compile 'com.github.kabouzeid:AppIntro:3.3.0k'
     compile 'com.github.bumptech.glide:glide:3.6.1'
-    compile 'com.github.kabouzeid:RecyclerView-FastScroll:v1.0-kmod'
+    compile 'com.github.kabouzeid:RecyclerView-FastScroll:v1.2-kmod'
 }

app/src/main/java/com/kabouzeid/gramophone/adapter/album/AlbumAdapter.java

@@ -24,7 +24,9 @@ import com.kabouzeid.gramophone.interfaces.CabHolder;
 import com.kabouzeid.gramophone.model.Album;
 import com.kabouzeid.gramophone.model.Song;
 import com.kabouzeid.gramophone.util.ColorUtil;
+import com.kabouzeid.gramophone.util.MusicUtil;
 import com.kabouzeid.gramophone.util.NavigationUtil;
+import com.simplecityapps.recyclerview_fastscroll.views.FastScrollRecyclerView;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -32,7 +34,7 @@ import java.util.List;
 /**
  * @author Karim Abou Zeid (kabouzeid)
  */
-public class AlbumAdapter extends AbsMultiSelectAdapter<AlbumAdapter.ViewHolder, Album> {
+public class AlbumAdapter extends AbsMultiSelectAdapter<AlbumAdapter.ViewHolder, Album> implements FastScrollRecyclerView.SectionedAdapter {
 
     public static final String TAG = AlbumAdapter.class.getSimpleName();
 
@@ -179,6 +181,12 @@ public class AlbumAdapter extends AbsMultiSelectAdapter<AlbumAdapter.ViewHolder,
         return songs;
     }
 
+    @NonNull
+    @Override
+    public String getSectionName(int position) {
+        return MusicUtil.getSectionName(dataSet.get(position).getTitle());
+    }
+
     public class ViewHolder extends MediaEntryViewHolder {
 
         public ViewHolder(@NonNull final View itemView) {

app/src/main/java/com/kabouzeid/gramophone/adapter/artist/ArtistAdapter.java

@@ -33,6 +33,7 @@ import com.kabouzeid.gramophone.util.ArtistSignatureUtil;
 import com.kabouzeid.gramophone.util.ColorUtil;
 import com.kabouzeid.gramophone.util.MusicUtil;
 import com.kabouzeid.gramophone.util.NavigationUtil;
+import com.simplecityapps.recyclerview_fastscroll.views.FastScrollRecyclerView;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -40,7 +41,7 @@ import java.util.List;
 /**
  * @author Karim Abou Zeid (kabouzeid)
  */
-public class ArtistAdapter extends AbsMultiSelectAdapter<ArtistAdapter.ViewHolder, Artist> {
+public class ArtistAdapter extends AbsMultiSelectAdapter<ArtistAdapter.ViewHolder, Artist> implements FastScrollRecyclerView.SectionedAdapter {
 
     protected final AppCompatActivity activity;
     protected ArrayList<Artist> dataSet;
@@ -185,6 +186,12 @@ public class ArtistAdapter extends AbsMultiSelectAdapter<ArtistAdapter.ViewHolde
         return songs;
     }
 
+    @NonNull
+    @Override
+    public String getSectionName(int position) {
+        return MusicUtil.getSectionName(dataSet.get(position).name);
+    }
+
     public class ViewHolder extends MediaEntryViewHolder {
 
         public ViewHolder(@NonNull View itemView) {

app/src/main/java/com/kabouzeid/gramophone/adapter/song/ShuffleButtonSongAdapter.java

@@ -99,6 +99,14 @@ public class ShuffleButtonSongAdapter extends SongAdapter {
         }
     }
 
+    @NonNull
+    @Override
+    public String getSectionName(int position) {
+        position--;
+        if (position < 0) return "";
+        return super.getSectionName(position);
+    }
+
     public class ViewHolder extends SongAdapter.ViewHolder {
 
         public ViewHolder(@NonNull View itemView) {

app/src/main/java/com/kabouzeid/gramophone/adapter/song/SongAdapter.java

@@ -10,6 +10,7 @@ import android.view.LayoutInflater;
 import android.view.MenuItem;
 import android.view.View;
 import android.view.ViewGroup;
+import android.widget.SectionIndexer;
 
 import com.afollestad.materialcab.MaterialCab;
 import com.bumptech.glide.Glide;
@@ -25,17 +26,19 @@ import com.kabouzeid.gramophone.helper.menu.SongMenuHelper;
 import com.kabouzeid.gramophone.interfaces.CabHolder;
 import com.kabouzeid.gramophone.model.Song;
 import com.kabouzeid.gramophone.util.ColorUtil;
+import com.kabouzeid.gramophone.util.MusicUtil;
 import com.kabouzeid.gramophone.util.NavigationUtil;
+import com.simplecityapps.recyclerview_fastscroll.views.FastScrollRecyclerView;
 
+import java.io.CharArrayReader;
 import java.util.ArrayList;
 
 /**
  * @author Karim Abou Zeid (kabouzeid)
  */
-public class SongAdapter extends AbsMultiSelectAdapter<SongAdapter.ViewHolder, Song> implements MaterialCab.Callback {
+public class SongAdapter extends AbsMultiSelectAdapter<SongAdapter.ViewHolder, Song> implements MaterialCab.Callback, FastScrollRecyclerView.SectionedAdapter {
 
     public static final String TAG = AlbumSongAdapter.class.getSimpleName();
-    private static final int FADE_IN_TIME = 500;
 
     protected final AppCompatActivity activity;
     protected ArrayList<Song> dataSet;
@@ -175,6 +178,12 @@ public class SongAdapter extends AbsMultiSelectAdapter<SongAdapter.ViewHolder, S
         }
     }
 
+    @NonNull
+    @Override
+    public String getSectionName(int position) {
+        return MusicUtil.getSectionName(dataSet.get(position).title);
+    }
+
     public class ViewHolder extends MediaEntryViewHolder {
         protected int DEFAULT_MENU_RES = SongMenuHelper.MENU_RES;
 

app/src/main/java/com/kabouzeid/gramophone/ui/fragments/mainactivityfragments/AbsMainActivityRecyclerViewFragment.java

@@ -13,8 +13,11 @@ import android.view.View;
 import android.view.ViewGroup;
 import android.widget.TextView;
 
+import com.afollestad.materialdialogs.internal.ThemeSingleton;
 import com.kabouzeid.gramophone.R;
 import com.kabouzeid.gramophone.interfaces.MusicServiceEventListener;
+import com.kabouzeid.gramophone.util.ColorUtil;
+import com.simplecityapps.recyclerview_fastscroll.views.FastScrollRecyclerView;
 
 import butterknife.Bind;
 import butterknife.ButterKnife;
@@ -57,6 +60,13 @@ public abstract class AbsMainActivityRecyclerViewFragment<A extends RecyclerView
     }
 
     private void setUpRecyclerView() {
+        if (recyclerView instanceof FastScrollRecyclerView) {
+            int accentColor = ThemeSingleton.get().positiveColor.getDefaultColor();
+            ((FastScrollRecyclerView) recyclerView).setPopupBgColor(accentColor);
+            ((FastScrollRecyclerView) recyclerView).setPopupTextColor(ColorUtil.getPrimaryTextColorForBackground(getActivity(), accentColor));
+            ((FastScrollRecyclerView) recyclerView).setThumbColor(accentColor);
+            ((FastScrollRecyclerView) recyclerView).setTrackColor(ColorUtil.getColorWithAlpha(0.12f, ColorUtil.resolveColor(getContext(), R.attr.colorControlNormal)));
+        }
         invalidateLayoutManager();
         invalidateAdapter();
     }

app/src/main/java/com/kabouzeid/gramophone/util/MusicUtil.java

@@ -13,6 +13,7 @@ import android.provider.MediaStore;
 import android.provider.Settings;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
+import android.text.TextUtils;
 import android.util.Log;
 import android.widget.Toast;
 
@@ -224,7 +225,22 @@ public class MusicUtil {
         }
     }
 
-    public static boolean isArtistNameUnknown(@Nullable final String artistName) {
+    public static boolean isArtistNameUnknown(@Nullable String artistName) {
-        return artistName != null && (artistName.trim().toLowerCase().equals("unknown") || artistName.trim().toLowerCase().equals("<unknown>"));
+        if (TextUtils.isEmpty(artistName)) return false;
+        artistName = artistName.trim().toLowerCase();
+        return artistName.equals("unknown") || artistName.equals("<unknown>");
+    }
+
+    @NonNull
+    public static String getSectionName(@Nullable String musicMediaTitle) {
+        if (TextUtils.isEmpty(musicMediaTitle)) return "";
+        musicMediaTitle = musicMediaTitle.trim().toLowerCase();
+        if (musicMediaTitle.startsWith("the ")) {
+            musicMediaTitle = musicMediaTitle.substring(4);
+        } else if (musicMediaTitle.startsWith("a ")) {
+            musicMediaTitle = musicMediaTitle.substring(2);
+        }
+        if (musicMediaTitle.isEmpty()) return "";
+        return String.valueOf(musicMediaTitle.charAt(0)).toUpperCase();
     }
 }