diff --git a/app/src/main/java/io/legado/app/ui/readbook/ReadBookActivity.kt b/app/src/main/java/io/legado/app/ui/readbook/ReadBookActivity.kt
index d4a8f128a..7c6c2d780 100644
--- a/app/src/main/java/io/legado/app/ui/readbook/ReadBookActivity.kt
+++ b/app/src/main/java/io/legado/app/ui/readbook/ReadBookActivity.kt
@@ -7,6 +7,7 @@ import android.view.MenuItem
 import android.view.animation.Animation
 import android.view.animation.AnimationUtils
 import androidx.core.view.isVisible
+import androidx.lifecycle.Observer
 import io.legado.app.App
 import io.legado.app.R
 import io.legado.app.base.VMBaseActivity
@@ -39,6 +40,7 @@ class ReadBookActivity : VMBaseActivity<ReadBookViewModel>(R.layout.activity_rea
         setSupportActionBar(toolbar)
         initAnimation()
         initView()
+        viewModel.chapterMaxIndex.observe(this, Observer { })
         viewModel.initData(intent)
         savedInstanceState?.let {
             changeSourceDialog = supportFragmentManager.findFragmentByTag(ChangeSourceDialog.tag) as? ChangeSourceDialog
diff --git a/app/src/main/java/io/legado/app/ui/readbook/ReadBookViewModel.kt b/app/src/main/java/io/legado/app/ui/readbook/ReadBookViewModel.kt
index 0daa33437..da91edc8a 100644
--- a/app/src/main/java/io/legado/app/ui/readbook/ReadBookViewModel.kt
+++ b/app/src/main/java/io/legado/app/ui/readbook/ReadBookViewModel.kt
@@ -6,6 +6,7 @@ import androidx.lifecycle.MediatorLiveData
 import io.legado.app.App
 import io.legado.app.base.BaseViewModel
 import io.legado.app.data.entities.Book
+import io.legado.app.data.entities.BookChapter
 import io.legado.app.data.entities.BookSource
 import io.legado.app.help.BookHelp
 import io.legado.app.model.WebBook
@@ -47,14 +48,20 @@ class ReadBookViewModel(application: Application) : BaseViewModel(application) {
     }
 
 
-    fun download(book: Book, index: Int) {
+    fun getContent(book: Book, index: Int) {
         App.db.bookChapterDao().getChapter(book.bookUrl, index)?.let { chapter ->
-            webBook?.getContent(book, chapter)
-                ?.onSuccess(IO) { content ->
-                    content?.let {
-                        BookHelp.saveContent(book, chapter, it)
-                    }
-                }
+            BookHelp.getContent(book, chapter)?.let {
+
+            } ?: download(book, chapter)
         }
     }
+
+    private fun download(book: Book, chapter: BookChapter) {
+        webBook?.getContent(book, chapter)
+            ?.onSuccess(IO) { content ->
+                content?.let {
+                    BookHelp.saveContent(book, chapter, it)
+                }
+            }
+    }
 }
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