feat: 优化代码

app/src/main/java/io/legado/app/data/dao/BookDao.kt

@@ -33,6 +33,9 @@ interface BookDao {
     @Query("SELECT * FROM books WHERE name like '%'||:key||'%' or author like '%'||:key||'%'")
     fun liveDataSearch(key: String): LiveData<List<Book>>
 
+    @Query("SELECT * FROM books WHERE (`group` & :group) > 0")
+    fun getBooksByGroup(group: Int): List<Book>
+
     @Query("SELECT * FROM books WHERE `name` in (:names)")
     fun findByName(vararg names: String): List<Book>
 

app/src/main/java/io/legado/app/ui/book/group/GroupViewModel.kt

@@ -32,6 +32,13 @@ class GroupViewModel(application: Application) : BaseViewModel(application) {
     fun delGroup(vararg bookGroup: BookGroup) {
         execute {
             App.db.bookGroupDao().delete(*bookGroup)
+            bookGroup.forEach { group ->
+                val books = App.db.bookDao().getBooksByGroup(group.groupId)
+                books.forEach {
+                    it.group = it.group - group.groupId
+                }
+                App.db.bookDao().update(*books.toTypedArray())
+            }
         }
     }