优化

app/src/main/java/io/legado/app/ui/book/read/ReadBookViewModel.kt

@@ -105,11 +105,13 @@ class ReadBookViewModel(application: Application) : BaseViewModel(application) {
             } else {
                 ReadBook.loadContent(resetPageOffset = true)
             }
+            checkLocalBookFileExist(book)
         } else {
             if (ReadBook.durChapterIndex > ReadBook.chapterSize - 1) {
                 ReadBook.durChapterIndex = ReadBook.chapterSize - 1
             }
             ReadBook.loadContent(resetPageOffset = false)
+            checkLocalBookFileExist(book)
         }
         if (ReadBook.chapterChanged) {
             // 有章节跳转不同步阅读进度
@@ -123,6 +125,18 @@ class ReadBookViewModel(application: Application) : BaseViewModel(application) {
         }
     }
 
+    private fun checkLocalBookFileExist(book: Book) {
+        if (book.isLocal) {
+            execute {
+                LocalBook.getBookInputStream(book)
+            }.onError {
+                if (it is FileNotFoundException) {
+                    permissionDenialLiveData.postValue(0)
+                }
+            }
+        }
+    }
+
     /**
      * 加载详情页
      */