diff --git a/app/src/main/java/io/legado/app/ui/book/arrange/ArrangeBookActivity.kt b/app/src/main/java/io/legado/app/ui/book/arrange/ArrangeBookActivity.kt
index b66a3c911..654eda904 100644
--- a/app/src/main/java/io/legado/app/ui/book/arrange/ArrangeBookActivity.kt
+++ b/app/src/main/java/io/legado/app/ui/book/arrange/ArrangeBookActivity.kt
@@ -88,7 +88,7 @@ class ArrangeBookActivity : VMBaseActivity<ActivityArrangeBookBinding, ArrangeBo
         val itemTouchCallback = ItemTouchCallback(adapter)
         itemTouchCallback.isCanDrag = getPrefInt(PreferKey.bookshelfSort) == 3
         val dragSelectTouchHelper: DragSelectTouchHelper =
-            DragSelectTouchHelper(adapter.initDragSelectTouchHelperCallback()).setSlideArea(16, 50)
+            DragSelectTouchHelper(adapter.dragSelectCallback).setSlideArea(16, 50)
         dragSelectTouchHelper.attachToRecyclerView(binding.recyclerView)
         // When this page is opened, it is in selection mode
         dragSelectTouchHelper.activeSlideSelect()
diff --git a/app/src/main/java/io/legado/app/ui/book/arrange/ArrangeBookAdapter.kt b/app/src/main/java/io/legado/app/ui/book/arrange/ArrangeBookAdapter.kt
index a08253452..7fa4d5a19 100644
--- a/app/src/main/java/io/legado/app/ui/book/arrange/ArrangeBookAdapter.kt
+++ b/app/src/main/java/io/legado/app/ui/book/arrange/ArrangeBookAdapter.kt
@@ -165,8 +165,8 @@ class ArrangeBookAdapter(context: Context, val callBack: CallBack) :
         isMoved = false
     }
 
-    fun initDragSelectTouchHelperCallback(): DragSelectTouchHelper.Callback {
-        return object : DragSelectTouchHelper.AdvanceCallback<Book>(Mode.ToggleAndReverse) {
+    val dragSelectCallback: DragSelectTouchHelper.Callback =
+        object : DragSelectTouchHelper.AdvanceCallback<Book>(Mode.ToggleAndReverse) {
             override fun currentSelectedId(): MutableSet<Book> {
                 return selectedBooks
             }
@@ -189,7 +189,6 @@ class ArrangeBookAdapter(context: Context, val callBack: CallBack) :
                 return false
             }
         }
-    }
 
     interface CallBack {
         val groupList: List<BookGroup>
diff --git a/app/src/main/java/io/legado/app/ui/book/search/SearchActivity.kt b/app/src/main/java/io/legado/app/ui/book/search/SearchActivity.kt
index dbabfd209..0db6df716 100644
--- a/app/src/main/java/io/legado/app/ui/book/search/SearchActivity.kt
+++ b/app/src/main/java/io/legado/app/ui/book/search/SearchActivity.kt
@@ -237,22 +237,22 @@ class SearchActivity : VMBaseActivity<ActivityBookSearchBinding, SearchViewModel
     /**
      * 更新分组菜单
      */
-    private fun upGroupMenu() {
+    private fun upGroupMenu() = menu?.let { menu ->
         val selectedGroup = getPrefString("searchGroup") ?: ""
-        menu?.removeGroup(R.id.source_group)
-        var item = menu?.add(R.id.source_group, Menu.NONE, Menu.NONE, R.string.all_source)
+        menu.removeGroup(R.id.source_group)
+        var item = menu.add(R.id.source_group, Menu.NONE, Menu.NONE, R.string.all_source)
         if (selectedGroup == "") {
             item?.isChecked = true
         }
         groups.sortedWith { o1, o2 ->
             o1.cnCompare(o2)
         }.map {
-            item = menu?.add(R.id.source_group, Menu.NONE, Menu.NONE, it)
+            item = menu.add(R.id.source_group, Menu.NONE, Menu.NONE, it)
             if (it == selectedGroup) {
                 item?.isChecked = true
             }
         }
-        menu?.setGroupCheckable(R.id.source_group, true, true)
+        menu.setGroupCheckable(R.id.source_group, true, true)
     }
 
     /**
diff --git a/app/src/main/java/io/legado/app/ui/book/source/manage/BookSourceActivity.kt b/app/src/main/java/io/legado/app/ui/book/source/manage/BookSourceActivity.kt
index d82af267a..026f02a4d 100644
--- a/app/src/main/java/io/legado/app/ui/book/source/manage/BookSourceActivity.kt
+++ b/app/src/main/java/io/legado/app/ui/book/source/manage/BookSourceActivity.kt
@@ -152,14 +152,14 @@ class BookSourceActivity : VMBaseActivity<ActivityBookSourceBinding, BookSourceV
         binding.recyclerView.addItemDecoration(VerticalDivider(this))
         adapter = BookSourceAdapter(this, this)
         binding.recyclerView.adapter = adapter
-        val itemTouchCallback = ItemTouchCallback(adapter)
-        itemTouchCallback.isCanDrag = true
+        // When this page is opened, it is in selection mode
         val dragSelectTouchHelper: DragSelectTouchHelper =
-            DragSelectTouchHelper(adapter.initDragSelectTouchHelperCallback()).setSlideArea(16, 50)
+            DragSelectTouchHelper(adapter.dragSelectCallback).setSlideArea(16, 50)
         dragSelectTouchHelper.attachToRecyclerView(binding.recyclerView)
-        // When this page is opened, it is in selection mode
         dragSelectTouchHelper.activeSlideSelect()
         // Note: need judge selection first, so add ItemTouchHelper after it.
+        val itemTouchCallback = ItemTouchCallback(adapter)
+        itemTouchCallback.isCanDrag = true
         ItemTouchHelper(itemTouchCallback).attachToRecyclerView(binding.recyclerView)
     }
 
@@ -339,12 +339,12 @@ class BookSourceActivity : VMBaseActivity<ActivityBookSourceBinding, BookSourceV
         }.show()
     }
 
-    private fun upGroupMenu() {
-        groupMenu?.removeGroup(R.id.source_group)
+    private fun upGroupMenu() = groupMenu?.let { menu ->
+        menu.removeGroup(R.id.source_group)
         groups.sortedWith { o1, o2 ->
             o1.cnCompare(o2)
         }.map {
-            groupMenu?.add(R.id.source_group, Menu.NONE, Menu.NONE, it)
+            menu.add(R.id.source_group, Menu.NONE, Menu.NONE, it)
         }
     }
 
diff --git a/app/src/main/java/io/legado/app/ui/book/source/manage/BookSourceAdapter.kt b/app/src/main/java/io/legado/app/ui/book/source/manage/BookSourceAdapter.kt
index fe090435b..93fc4fdfd 100644
--- a/app/src/main/java/io/legado/app/ui/book/source/manage/BookSourceAdapter.kt
+++ b/app/src/main/java/io/legado/app/ui/book/source/manage/BookSourceAdapter.kt
@@ -204,8 +204,8 @@ class BookSourceAdapter(context: Context, val callBack: CallBack) :
         }
     }
 
-    fun initDragSelectTouchHelperCallback(): DragSelectTouchHelper.Callback {
-        return object : DragSelectTouchHelper.AdvanceCallback<BookSource>(Mode.ToggleAndReverse) {
+    val dragSelectCallback: DragSelectTouchHelper.Callback =
+        object : DragSelectTouchHelper.AdvanceCallback<BookSource>(Mode.ToggleAndReverse) {
             override fun currentSelectedId(): MutableSet<BookSource> {
                 return selected
             }
@@ -228,7 +228,6 @@ class BookSourceAdapter(context: Context, val callBack: CallBack) :
                 return false
             }
         }
-    }
 
     interface CallBack {
         fun del(bookSource: BookSource)
diff --git a/app/src/main/java/io/legado/app/ui/main/explore/ExploreFragment.kt b/app/src/main/java/io/legado/app/ui/main/explore/ExploreFragment.kt
index 0967a106e..e4ea63bd7 100644
--- a/app/src/main/java/io/legado/app/ui/main/explore/ExploreFragment.kt
+++ b/app/src/main/java/io/legado/app/ui/main/explore/ExploreFragment.kt
@@ -123,14 +123,12 @@ class ExploreFragment : VMBaseFragment<ExploreViewModel>(R.layout.fragment_explo
         })
     }
 
-    private fun upGroupsMenu() {
-        groupsMenu?.let { subMenu ->
-            subMenu.removeGroup(R.id.menu_group_text)
-            groups.sortedWith { o1, o2 ->
-                o1.cnCompare(o2)
-            }.forEach {
-                subMenu.add(R.id.menu_group_text, Menu.NONE, Menu.NONE, it)
-            }
+    private fun upGroupsMenu() = groupsMenu?.let { subMenu ->
+        subMenu.removeGroup(R.id.menu_group_text)
+        groups.sortedWith { o1, o2 ->
+            o1.cnCompare(o2)
+        }.forEach {
+            subMenu.add(R.id.menu_group_text, Menu.NONE, Menu.NONE, it)
         }
     }
 
diff --git a/app/src/main/java/io/legado/app/ui/replace/ReplaceRuleActivity.kt b/app/src/main/java/io/legado/app/ui/replace/ReplaceRuleActivity.kt
index a24c52943..b527aaade 100644
--- a/app/src/main/java/io/legado/app/ui/replace/ReplaceRuleActivity.kt
+++ b/app/src/main/java/io/legado/app/ui/replace/ReplaceRuleActivity.kt
@@ -92,7 +92,7 @@ class ReplaceRuleActivity : VMBaseActivity<ActivityReplaceRuleBinding, ReplaceRu
         val itemTouchCallback = ItemTouchCallback(adapter)
         itemTouchCallback.isCanDrag = true
         val dragSelectTouchHelper: DragSelectTouchHelper =
-            DragSelectTouchHelper(adapter.initDragSelectTouchHelperCallback()).setSlideArea(16, 50)
+            DragSelectTouchHelper(adapter.dragSelectCallback).setSlideArea(16, 50)
         dragSelectTouchHelper.attachToRecyclerView(binding.recyclerView)
         // When this page is opened, it is in selection mode
         dragSelectTouchHelper.activeSlideSelect()
diff --git a/app/src/main/java/io/legado/app/ui/replace/ReplaceRuleAdapter.kt b/app/src/main/java/io/legado/app/ui/replace/ReplaceRuleAdapter.kt
index 89c81788e..0cc906a31 100644
--- a/app/src/main/java/io/legado/app/ui/replace/ReplaceRuleAdapter.kt
+++ b/app/src/main/java/io/legado/app/ui/replace/ReplaceRuleAdapter.kt
@@ -167,8 +167,8 @@ class ReplaceRuleAdapter(context: Context, var callBack: CallBack) :
         }
     }
 
-    fun initDragSelectTouchHelperCallback(): DragSelectTouchHelper.Callback {
-        return object : DragSelectTouchHelper.AdvanceCallback<ReplaceRule>(Mode.ToggleAndReverse) {
+    val dragSelectCallback: DragSelectTouchHelper.Callback =
+        object : DragSelectTouchHelper.AdvanceCallback<ReplaceRule>(Mode.ToggleAndReverse) {
             override fun currentSelectedId(): MutableSet<ReplaceRule> {
                 return selected
             }
@@ -191,7 +191,6 @@ class ReplaceRuleAdapter(context: Context, var callBack: CallBack) :
                 return false
             }
         }
-    }
 
     interface CallBack {
         fun update(vararg rule: ReplaceRule)
diff --git a/app/src/main/java/io/legado/app/ui/rss/source/manage/RssSourceActivity.kt b/app/src/main/java/io/legado/app/ui/rss/source/manage/RssSourceActivity.kt
index 8e3c4f78b..01abc2e16 100644
--- a/app/src/main/java/io/legado/app/ui/rss/source/manage/RssSourceActivity.kt
+++ b/app/src/main/java/io/legado/app/ui/rss/source/manage/RssSourceActivity.kt
@@ -121,13 +121,11 @@ class RssSourceActivity : VMBaseActivity<ActivityRssSourceBinding, RssSourceView
         binding.recyclerView.addItemDecoration(VerticalDivider(this))
         adapter = RssSourceAdapter(this, this)
         binding.recyclerView.adapter = adapter
-
+        // When this page is opened, it is in selection mode
         val dragSelectTouchHelper: DragSelectTouchHelper =
-            DragSelectTouchHelper(adapter.initDragSelectTouchHelperCallback()).setSlideArea(16, 50)
+            DragSelectTouchHelper(adapter.dragSelectCallback).setSlideArea(16, 50)
         dragSelectTouchHelper.attachToRecyclerView(binding.recyclerView)
-        // When this page is opened, it is in selection mode
         dragSelectTouchHelper.activeSlideSelect()
-
         // Note: need judge selection first, so add ItemTouchHelper after it.
         val itemTouchCallback = ItemTouchCallback(adapter)
         itemTouchCallback.isCanDrag = true
@@ -193,12 +191,12 @@ class RssSourceActivity : VMBaseActivity<ActivityRssSourceBinding, RssSourceView
         }.show()
     }
 
-    private fun upGroupMenu() {
-        groupMenu?.removeGroup(R.id.source_group)
+    private fun upGroupMenu() = groupMenu?.let { menu ->
+        menu.removeGroup(R.id.source_group)
         groups.sortedWith { o1, o2 ->
             o1.cnCompare(o2)
         }.map {
-            groupMenu?.add(R.id.source_group, Menu.NONE, Menu.NONE, it)
+            menu.add(R.id.source_group, Menu.NONE, Menu.NONE, it)
         }
     }
 
diff --git a/app/src/main/java/io/legado/app/ui/rss/source/manage/RssSourceAdapter.kt b/app/src/main/java/io/legado/app/ui/rss/source/manage/RssSourceAdapter.kt
index 60128fb27..1de2c8ebe 100644
--- a/app/src/main/java/io/legado/app/ui/rss/source/manage/RssSourceAdapter.kt
+++ b/app/src/main/java/io/legado/app/ui/rss/source/manage/RssSourceAdapter.kt
@@ -170,8 +170,8 @@ class RssSourceAdapter(context: Context, val callBack: CallBack) :
         }
     }
 
-    fun initDragSelectTouchHelperCallback(): DragSelectTouchHelper.Callback {
-        return object : DragSelectTouchHelper.AdvanceCallback<RssSource>(Mode.ToggleAndReverse) {
+    val dragSelectCallback: DragSelectTouchHelper.Callback =
+        object : DragSelectTouchHelper.AdvanceCallback<RssSource>(Mode.ToggleAndReverse) {
             override fun currentSelectedId(): MutableSet<RssSource> {
                 return selected
             }
@@ -194,7 +194,6 @@ class RssSourceAdapter(context: Context, val callBack: CallBack) :
                 return false
             }
         }
-    }
 
     interface CallBack {
         fun del(source: RssSource)