diff --git a/app/src/main/java/io/legado/app/help/AppConfig.kt b/app/src/main/java/io/legado/app/help/AppConfig.kt
index 01b02eac5..5a381cf73 100644
--- a/app/src/main/java/io/legado/app/help/AppConfig.kt
+++ b/app/src/main/java/io/legado/app/help/AppConfig.kt
@@ -143,7 +143,7 @@ object AppConfig : SharedPreferences.OnSharedPreferenceChangeListener {
         get() = appCtx.getPrefBoolean(PreferKey.autoRefresh)
 
     var threadCount: Int
-        get() = appCtx.getPrefInt(PreferKey.threadCount, 16)
+        get() = appCtx.getPrefInt(PreferKey.threadCount, 8)
         set(value) {
             appCtx.putPrefInt(PreferKey.threadCount, value)
         }
diff --git a/app/src/main/java/io/legado/app/ui/book/group/GroupEdit.kt b/app/src/main/java/io/legado/app/ui/book/group/GroupEdit.kt
new file mode 100644
index 000000000..9902ee15d
--- /dev/null
+++ b/app/src/main/java/io/legado/app/ui/book/group/GroupEdit.kt
@@ -0,0 +1,54 @@
+package io.legado.app.ui.book.group
+
+import android.content.Context
+import android.view.LayoutInflater
+import io.legado.app.R
+import io.legado.app.data.appDb
+import io.legado.app.data.entities.BookGroup
+import io.legado.app.databinding.DialogEditTextBinding
+import io.legado.app.help.coroutine.Coroutine
+import io.legado.app.lib.dialogs.alert
+import io.legado.app.utils.requestInputMethod
+
+object GroupEdit {
+
+    fun show(context: Context, layoutInflater: LayoutInflater, bookGroup: BookGroup) = context.run {
+        alert(title = getString(R.string.group_edit)) {
+            val alertBinding = DialogEditTextBinding.inflate(layoutInflater).apply {
+                editView.setHint(R.string.group_name)
+                editView.setText(bookGroup.groupName)
+            }
+            if (bookGroup.groupId >= 0) {
+                neutralButton(R.string.delete) {
+                    deleteGroup(context, bookGroup)
+                }
+            }
+            customView { alertBinding.root }
+            yesButton {
+                alertBinding.editView.text?.toString()?.let {
+                    Coroutine.async {
+                        appDb.bookGroupDao.update(bookGroup)
+                    }
+                }
+            }
+            noButton()
+        }.show().requestInputMethod()
+    }
+
+    private fun deleteGroup(context: Context, bookGroup: BookGroup) = context.run {
+        alert(R.string.delete, R.string.sure_del) {
+            okButton {
+                Coroutine.async {
+                    appDb.bookGroupDao.delete(bookGroup)
+                    val books = appDb.bookDao.getBooksByGroup(bookGroup.groupId)
+                    books.forEach {
+                        it.group = it.group - bookGroup.groupId
+                    }
+                    appDb.bookDao.update(*books.toTypedArray())
+                }
+            }
+            noButton()
+        }.show()
+    }
+
+}
\ No newline at end of file
diff --git a/app/src/main/java/io/legado/app/ui/book/group/GroupManageDialog.kt b/app/src/main/java/io/legado/app/ui/book/group/GroupManageDialog.kt
index af5de0d90..ca6271a15 100644
--- a/app/src/main/java/io/legado/app/ui/book/group/GroupManageDialog.kt
+++ b/app/src/main/java/io/legado/app/ui/book/group/GroupManageDialog.kt
@@ -117,37 +117,6 @@ class GroupManageDialog : BaseDialogFragment(), Toolbar.OnMenuItemClickListener
         }.show().requestInputMethod()
     }
 
-    @SuppressLint("InflateParams")
-    private fun editGroup(bookGroup: BookGroup) {
-        alert(title = getString(R.string.group_edit)) {
-            val alertBinding = DialogEditTextBinding.inflate(layoutInflater).apply {
-                editView.setHint(R.string.group_name)
-                editView.setText(bookGroup.groupName)
-            }
-            if (bookGroup.groupId >= 0) {
-                neutralButton(R.string.delete) {
-                    deleteGroup(bookGroup)
-                }
-            }
-            customView { alertBinding.root }
-            yesButton {
-                alertBinding.editView.text?.toString()?.let {
-                    viewModel.upGroup(bookGroup.copy(groupName = it))
-                }
-            }
-            noButton()
-        }.show().requestInputMethod()
-    }
-
-    private fun deleteGroup(bookGroup: BookGroup) {
-        alert(R.string.delete, R.string.sure_del) {
-            okButton {
-                viewModel.delGroup(bookGroup)
-            }
-            noButton()
-        }.show()
-    }
-
     private inner class GroupAdapter(context: Context) :
         RecyclerAdapter<BookGroup, ItemBookGroupManageBinding>(context),
         ItemTouchCallback.Callback {
@@ -173,7 +142,11 @@ class GroupManageDialog : BaseDialogFragment(), Toolbar.OnMenuItemClickListener
 
         override fun registerListener(holder: ItemViewHolder, binding: ItemBookGroupManageBinding) {
             binding.run {
-                tvEdit.setOnClickListener { getItem(holder.layoutPosition)?.let { editGroup(it) } }
+                tvEdit.setOnClickListener {
+                    getItem(holder.layoutPosition)?.let { bookGroup ->
+                        GroupEdit.show(context, layoutInflater, bookGroup)
+                    }
+                }
                 swShow.setOnCheckedChangeListener { buttonView, isChecked ->
                     if (buttonView.isPressed) {
                         getItem(holder.layoutPosition)?.let {
diff --git a/app/src/main/java/io/legado/app/ui/main/bookshelf/style2/BookshelfFragment2.kt b/app/src/main/java/io/legado/app/ui/main/bookshelf/style2/BookshelfFragment2.kt
index aada477e8..6e433dec9 100644
--- a/app/src/main/java/io/legado/app/ui/main/bookshelf/style2/BookshelfFragment2.kt
+++ b/app/src/main/java/io/legado/app/ui/main/bookshelf/style2/BookshelfFragment2.kt
@@ -22,6 +22,7 @@ import io.legado.app.help.AppConfig
 import io.legado.app.lib.theme.ATH
 import io.legado.app.lib.theme.accentColor
 import io.legado.app.ui.book.audio.AudioPlayActivity
+import io.legado.app.ui.book.group.GroupEdit
 import io.legado.app.ui.book.info.BookInfoActivity
 import io.legado.app.ui.book.read.ReadBookActivity
 import io.legado.app.ui.book.search.SearchActivity
@@ -52,7 +53,6 @@ class BookshelfFragment2 : BaseBookshelfFragment(R.layout.fragment_bookshelf1),
     override var books: List<Book> = emptyList()
 
     override fun onFragmentCreated(view: View, savedInstanceState: Bundle?) {
-        searchView = binding.titleBar.findViewById(R.id.search_view)
         setSupportToolbar(binding.titleBar.toolbar)
         initRecyclerView()
         initGroupData()
@@ -159,34 +159,30 @@ class BookshelfFragment2 : BaseBookshelfFragment(R.layout.fragment_bookshelf1),
     }
 
     override fun onItemClick(position: Int) {
-        if (position < bookGroups.size) {
-            val bookGroup = bookGroups[position]
-            groupId = bookGroup.groupId
-            initBooksData()
-        } else {
-            val book = books[position - bookGroups.size]
-            when (book.type) {
+        when (val item = getItem(position)) {
+            is Book -> when (item.type) {
                 BookType.audio ->
                     startActivity<AudioPlayActivity> {
-                        putExtra("bookUrl", book.bookUrl)
+                        putExtra("bookUrl", item.bookUrl)
                     }
                 else -> startActivity<ReadBookActivity> {
-                    putExtra("bookUrl", book.bookUrl)
+                    putExtra("bookUrl", item.bookUrl)
                 }
             }
+            is BookGroup -> {
+                groupId = item.groupId
+                initBooksData()
+            }
         }
     }
 
     override fun onItemLongClick(position: Int) {
-        if (position < bookGroups.size) {
-            groupId = bookGroups[position].groupId
-            initBooksData()
-        } else {
-            val book = books[position - bookGroups.size]
-            startActivity<BookInfoActivity> {
-                putExtra("name", book.name)
-                putExtra("author", book.author)
+        when (val item = getItem(position)) {
+            is Book -> startActivity<BookInfoActivity> {
+                putExtra("name", item.name)
+                putExtra("author", item.author)
             }
+            is BookGroup -> GroupEdit.show(requireContext(), layoutInflater, item)
         }
     }