优化

app/src/main/java/io/legado/app/ui/config/BackupConfigFragment.kt

@@ -139,9 +139,12 @@ class BackupConfigFragment : PreferenceFragment(),
 
     override fun onMenuItemSelected(menuItem: MenuItem): Boolean {
         when (menuItem.itemId) {
-            R.id.menu_help -> showHelp()
+            R.id.menu_help -> {
+                showHelp()
+                return true
+            }
         }
-        return true
+        return false
     }
 
     private fun showHelp() {

app/src/main/java/io/legado/app/ui/config/ThemeConfigFragment.kt

@@ -114,9 +114,10 @@ class ThemeConfigFragment : PreferenceFragment(),
             R.id.menu_theme_mode -> {
                 AppConfig.isNightTheme = !AppConfig.isNightTheme
                 ThemeConfig.applyDayNight(requireContext())
+                return true
             }
         }
-        return true
+        return false
     }
 
     override fun onSharedPreferenceChanged(sharedPreferences: SharedPreferences?, key: String?) {