[skip ci] 优化

app/src/main/java/io/legado/app/model/localBook/EpubFile.kt

@@ -74,10 +74,16 @@ class EpubFile(var book: Book) {
     private var fileDescriptor: ParcelFileDescriptor? = null
     private var epubBook: EpubBook? = null
         get() {
-            if (field != null && fileDescriptor != null) {
-                return field
+            if (field == null || fileDescriptor == null) {
+                field = readEpub()
+            }
+            return field
+        }
+    private var epubBookContents: List<Resource>?
+        get() {
+            if (field == null || fileDescriptor == null) {
+                field = epubBook.contents
             }
-            field = readEpub()
             return field
         }
 
@@ -147,7 +153,7 @@ class EpubFile(var book: Book) {
             val includeNextChapterResource = !endFragmentId.isNullOrBlank()
             /*一些书籍依靠href索引的resource会包含多个章节，需要依靠fragmentId来截取到当前章节的内容*/
             /*注:这里较大增加了内容加载的时间，所以首次获取内容后可存储到本地cache，减少重复加载*/
-            for (res in epubBook.contents) {
+            for (res in epubBookContents) {
                 if (!findChapterFirstSource) {
                     if (currentChapterFirstResourceHref != res.href) continue
                     findChapterFirstSource = true

app/src/main/java/io/legado/app/ui/book/info/BookInfoViewModel.kt

@@ -155,12 +155,12 @@ class BookInfoViewModel(application: Application) : BaseViewModel(application) {
                             appDb.bookDao.getBook(book.name, book.author)?.let {
                                 inBookshelf = true
                             }
-                            bookData.postValue(book)
+                            bookData.postValue(it)
                             if (inBookshelf) {
-                                appDb.bookDao.update(book)
+                                appDb.bookDao.update(it)
                             }
                             if (it.isWebFile) {
-                                loadWebFile(book, bookSource, scope)
+                                loadWebFile(it, scope)
                             } else {
                                 loadChapter(it, scope)
                             }
@@ -234,7 +234,6 @@ class BookInfoViewModel(application: Application) : BaseViewModel(application) {
 
     private fun loadWebFile(
         book: Book,
-        bookSource: BookSource,
         scope: CoroutineScope = viewModelScope
     ) {
         execute(scope) {
@@ -263,6 +262,7 @@ class BookInfoViewModel(application: Application) : BaseViewModel(application) {
                LocalBook.saveBookFile(webFile.url, webFile.name, bookSource)
            }
        }.onSuccess {
+           @Suppress("unchecked_cast")
            success?.invoke(it as T)
        }.onError {
            context.toastOnUi("ImportWebFileError\n${it.localizedMessage}")