diff --git a/app/src/main/java/io/legado/app/ui/book/changecover/DiffCallBack.kt b/app/src/main/java/io/legado/app/ui/book/changecover/DiffCallBack.kt
deleted file mode 100644
index 65d6fdd36..000000000
--- a/app/src/main/java/io/legado/app/ui/book/changecover/DiffCallBack.kt
+++ /dev/null
@@ -1,54 +0,0 @@
-package io.legado.app.ui.book.changecover
-
-import android.os.Bundle
-import androidx.recyclerview.widget.DiffUtil
-import io.legado.app.data.entities.SearchBook
-
-class DiffCallBack(
-    private val oldItems: List<SearchBook>,
-    private val newItems: List<SearchBook>
-) : DiffUtil.Callback() {
-
-    override fun getOldListSize(): Int {
-        return oldItems.size
-    }
-
-    override fun getNewListSize(): Int {
-        return newItems.size
-    }
-
-    override fun areItemsTheSame(oldItemPosition: Int, newItemPosition: Int): Boolean {
-        val oldItem = oldItems[oldItemPosition]
-        val newItem = newItems[newItemPosition]
-        return oldItem.bookUrl == newItem.bookUrl
-    }
-
-    override fun areContentsTheSame(oldItemPosition: Int, newItemPosition: Int): Boolean {
-        val oldItem = oldItems[oldItemPosition]
-        val newItem = newItems[newItemPosition]
-        if (oldItem.originName != newItem.originName) {
-            return false
-        }
-        if (oldItem.coverUrl != newItem.coverUrl) {
-            return false
-        }
-        return true
-    }
-
-    override fun getChangePayload(oldItemPosition: Int, newItemPosition: Int): Any? {
-        val oldItem = oldItems[oldItemPosition]
-        val newItem = newItems[newItemPosition]
-        val payload = Bundle()
-        if (oldItem.originName != newItem.originName) {
-            payload.putString("name", newItem.originName)
-        }
-        if (oldItem.coverUrl != newItem.coverUrl) {
-            payload.putString("coverUrl", newItem.coverUrl)
-        }
-        if (payload.isEmpty) {
-            return null
-        }
-        return payload
-    }
-
-}
\ No newline at end of file