diff --git a/app/src/main/java/io/legado/app/ui/book/read/page/delegate/PageDelegate.kt b/app/src/main/java/io/legado/app/ui/book/read/page/delegate/PageDelegate.kt
index 15ea770d7..b0be332dc 100644
--- a/app/src/main/java/io/legado/app/ui/book/read/page/delegate/PageDelegate.kt
+++ b/app/src/main/java/io/legado/app/ui/book/read/page/delegate/PageDelegate.kt
@@ -20,7 +20,7 @@ import kotlin.math.abs
 
 abstract class PageDelegate(protected val pageView: PageView) :
     GestureDetector.SimpleOnGestureListener() {
-    val centerRectF = RectF(
+    private val centerRectF = RectF(
         pageView.width * 0.33f, pageView.height * 0.33f,
         pageView.width * 0.66f, pageView.height * 0.66f
     )