From 2a53b9475429ee5ad6a293a8f839c61158c6a676 Mon Sep 17 00:00:00 2001
From: kunfei <gekunfei@live.com>
Date: Tue, 15 Oct 2019 13:33:12 +0800
Subject: [PATCH] up

---
 .../ui/main/bookshelf/BooksDiffCallBack.kt    | 33 +++++++++++++++++++
 .../app/ui/main/bookshelf/BooksFragment.kt    |  4 +++
 2 files changed, 37 insertions(+)
 create mode 100644 app/src/main/java/io/legado/app/ui/main/bookshelf/BooksDiffCallBack.kt

diff --git a/app/src/main/java/io/legado/app/ui/main/bookshelf/BooksDiffCallBack.kt b/app/src/main/java/io/legado/app/ui/main/bookshelf/BooksDiffCallBack.kt
new file mode 100644
index 000000000..c5b7d7c03
--- /dev/null
+++ b/app/src/main/java/io/legado/app/ui/main/bookshelf/BooksDiffCallBack.kt
@@ -0,0 +1,33 @@
+package io.legado.app.ui.main.bookshelf
+
+import androidx.recyclerview.widget.DiffUtil
+import io.legado.app.data.entities.Book
+
+class BooksDiffCallBack(private val oldItems: List<Book>, private val newItems: List<Book>) :
+    DiffUtil.Callback() {
+
+
+    override fun areItemsTheSame(oldItemPosition: Int, newItemPosition: Int): Boolean {
+        return oldItems[oldItemPosition].bookUrl == newItems[newItemPosition].bookUrl
+    }
+
+    override fun getOldListSize(): Int {
+        return oldItems.size
+    }
+
+    override fun getNewListSize(): Int {
+        return newItems.size
+    }
+
+    override fun areContentsTheSame(oldItemPosition: Int, newItemPosition: Int): Boolean {
+        val oldItem = oldItems[oldItemPosition]
+        val newItem = newItems[newItemPosition]
+        return oldItem.name == newItem.name
+                && oldItem.durChapterTitle == newItem.durChapterTitle
+                && oldItem.latestChapterTitle == newItem.latestChapterTitle
+                && oldItem.getDisplayCover() == newItem.getDisplayCover()
+                && oldItem.getUnreadChapterNum() == newItem.getUnreadChapterNum()
+                && oldItem.lastCheckCount == newItem.lastCheckCount
+    }
+
+}
\ No newline at end of file
diff --git a/app/src/main/java/io/legado/app/ui/main/bookshelf/BooksFragment.kt b/app/src/main/java/io/legado/app/ui/main/bookshelf/BooksFragment.kt
index 9c20f526b..f65337b52 100644
--- a/app/src/main/java/io/legado/app/ui/main/bookshelf/BooksFragment.kt
+++ b/app/src/main/java/io/legado/app/ui/main/bookshelf/BooksFragment.kt
@@ -5,6 +5,7 @@ import android.view.View
 import androidx.core.content.ContextCompat
 import androidx.lifecycle.LiveData
 import androidx.lifecycle.Observer
+import androidx.recyclerview.widget.DiffUtil
 import androidx.recyclerview.widget.DividerItemDecoration
 import androidx.recyclerview.widget.LinearLayoutManager
 import io.legado.app.App
@@ -86,7 +87,10 @@ class BooksFragment : VMBaseFragment<BooksViewModel>(R.layout.fragment_books),
         bookshelfLiveData?.observe(
             this,
             Observer {
+                val diffResult =
+                    DiffUtil.calculateDiff(BooksDiffCallBack(booksAdapter.getItems(), it))
                 booksAdapter.setItems(it)
+                diffResult.dispatchUpdatesTo(booksAdapter)
             })
     }