diff --git a/app/proguard-rules.pro b/app/proguard-rules.pro
index 1f75a763b..ec62ff5b8 100644
--- a/app/proguard-rules.pro
+++ b/app/proguard-rules.pro
@@ -100,7 +100,7 @@ cn.hutool.core.util.**{*;}
     *** mNavButtonView;
 }
 
-# FileDocExtensions.kt TreeDocumentFileConstructor
+# FileDocExtensions.kt treeDocumentFileConstructor
 -keep class androidx.documentfile.provider.TreeDocumentFile
 
 # JsoupXpath
diff --git a/app/src/main/java/io/legado/app/utils/FileDocExtensions.kt b/app/src/main/java/io/legado/app/utils/FileDocExtensions.kt
index 3751d92cc..2f8026e94 100644
--- a/app/src/main/java/io/legado/app/utils/FileDocExtensions.kt
+++ b/app/src/main/java/io/legado/app/utils/FileDocExtensions.kt
@@ -45,7 +45,7 @@ data class FileDoc(
     fun asDocumentFile(): DocumentFile? {
         if (isContentScheme) {
             return if (isDir) {
-                TreeDocumentFileConstructor.newInstance(null, appCtx, uri) as DocumentFile
+                treeDocumentFileConstructor.newInstance(null, appCtx, uri) as DocumentFile
             } else {
                 DocumentFile.fromSingleUri(appCtx, uri)
             }
@@ -62,7 +62,7 @@ data class FileDoc(
 
     companion object {
 
-        private val TreeDocumentFileConstructor by lazy {
+        private val treeDocumentFileConstructor by lazy {
             Class.forName("androidx.documentfile.provider.TreeDocumentFile")
                 .getDeclaredConstructor(
                     DocumentFile::class.java,