优化

app/src/main/java/io/legado/app/ui/book/toc/ChapterListAdapter.kt

@@ -19,6 +19,7 @@ class ChapterListAdapter(context: Context, val callback: Callback) :
     RecyclerAdapter<BookChapter, ItemChapterListBinding>(context) {
 
     val cacheFileNames = hashSetOf<String>()
+    val displayTileMap = hashMapOf<Int, String>()
     val diffCallBack = object : DiffUtil.ItemCallback<BookChapter>() {
 
         override fun areItemsTheSame(
@@ -47,6 +48,16 @@ class ChapterListAdapter(context: Context, val callback: Callback) :
         return ItemChapterListBinding.inflate(inflater, parent, false)
     }
 
+    private fun getDisplayTile(chapter: BookChapter): String {
+        var displayTile = displayTileMap[chapter.index]
+        if (displayTile != null) {
+            return displayTile
+