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
index ffdac0f79..1d1668acb 100644
--- 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
@@ -5,7 +5,8 @@ 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() {
+
+DiffUtil.Callback() {
 
     override fun getOldListSize(): Int {
         return oldItems.size