detail: improve track number handling

Improve the way track numbers are handled in the album detail view.

Previously, Auxio would show track numbers by simplying stringifying
the integer and then showing it in a TextView. This was problematic for
two reasons:
- Numerics from other languages like Arabic would not be respected
- Invalid track numbers [e.g 0] would be shown regardless of the
situation.

This commit fixes that by placing all track numbers through a format
string first, and showing a generic song icon instead of a number
whenever the track number is 0.

app/src/main/java/org/oxycblt/auxio/detail/recycler/AlbumDetailAdapter.kt

@@ -20,6 +20,7 @@ package org.oxycblt.auxio.detail.recycler
 
 import android.view.View
 import android.view.ViewGroup
+import androidx.core.view.isInvisible
 import androidx.recyclerview.widget.ListAdapter
 import androidx.recyclerview.widget.RecyclerView
 import org.oxycblt.auxio.R
@@ -178,13 +179,19 @@ class AlbumDetailAdapter(
     ) : BaseViewHolder<Song>(binding, doOnClick, doOnLongClick), Highlightable {
         override fun onBind(data: Song) {
             binding.song = data
-
             binding.songName.requestLayout()
+
+            // Hide the track number view if the track is zero, as generally a track number of
+            // zero implies that the song does not have a track number.
+            val usePlaceholder = data.track < 1
+            binding.songTrack.isInvisible = usePlaceholder
+            binding.songTrackPlaceholder.isInvisible = !usePlaceholder
         }
 
         override fun setHighlighted(isHighlighted: Boolean) {
             binding.songName.isActivated = isHighlighted
             binding.songTrack.isActivated = isHighlighted
+            binding.songTrackPlaceholder.isActivated = isHighlighted
         }
     }
 

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

@@ -13,6 +13,21 @@
 
     <androidx.constraintlayout.widget.ConstraintLayout style="@style/Widget.Auxio.ItemLayout">
 
+
+        <ImageView
+            android:id="@+id/song_track_placeholder"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:contentDescription="@string/def_track"
+            android:src="@drawable/ic_song"
+            android:visibility="gone"
+            app:tint="@color/sel_accented"
+            app:layout_constraintBottom_toBottomOf="@+id/song_track"
+            app:layout_constraintEnd_toEndOf="@+id/song_track"
+            app:layout_constraintStart_toStartOf="@+id/song_track"
+            app:layout_constraintTop_toTopOf="@+id/song_track"
+            tools:text="1" />
+
         <TextView
             android:id="@+id/song_track"
             android:layout_width="wrap_content"
@@ -21,12 +36,14 @@
             android:gravity="center"
             android:maxLines="1"
             android:minWidth="@dimen/size_track_number"
-            android:text="@{String.valueOf(song.track)}"
+            android:text="@{@string/fmt_track(song.track)}"
             android:textAlignment="center"
             android:textAppearance="@style/TextAppearance.Auxio.TitleMedium"
-            android:textSize="@dimen/text_size_ext_title_mid_larger"
             android:textColor="@color/sel_accented_secondary"
+            android:textSize="@dimen/text_size_ext_title_mid_larger"
             app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintEnd_toStartOf="@+id/song_name"
+            app:layout_constraintHorizontal_bias="0.5"
             app:layout_constraintStart_toStartOf="parent"
             app:layout_constraintTop_toTopOf="parent"
             tools:text="1" />

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

@@ -7,4 +7,5 @@
     <string name="fmt_two" translatable="false">%1$s • %2$s</string>
     <string name="fmt_three" translatable="false">%1$s • %2$s • %3$s</string>
     <string name="fmt_counts" translatable="false">%1$s, %2$s</string>
+    <string name="fmt_track" translatable="false">%d</string>
 </resources>

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

@@ -145,6 +145,7 @@
     <string name="def_artist">Unknown Artist</string>
     <string name="def_genre">Unknown Genre</string>
     <string name="def_date">No Date</string>
+    <string name="def_track">No Track Number</string>
     <string name="def_playback">No music playing</string>
     <string name="def_widget_song">Song Name</string>
     <string name="def_widget_artist">Artist Name</string>