diff --git a/app/src/main/java/io/legado/app/ui/book/source/manage/BookSourceActivity.kt b/app/src/main/java/io/legado/app/ui/book/source/manage/BookSourceActivity.kt
index 69f8133f7..49405ecbf 100644
--- a/app/src/main/java/io/legado/app/ui/book/source/manage/BookSourceActivity.kt
+++ b/app/src/main/java/io/legado/app/ui/book/source/manage/BookSourceActivity.kt
@@ -21,8 +21,6 @@ import io.legado.app.R
 import io.legado.app.base.VMBaseActivity
 import io.legado.app.data.entities.BookSource
 import io.legado.app.help.ItemTouchCallback
-import io.legado.app.help.permission.Permissions
-import io.legado.app.help.permission.PermissionsCompat
 import io.legado.app.lib.dialogs.*
 import io.legado.app.lib.theme.ATH
 import io.legado.app.lib.theme.primaryTextColor
@@ -42,7 +40,6 @@ import org.jetbrains.anko.startActivity
 import org.jetbrains.anko.startActivityForResult
 import org.jetbrains.anko.toast
 import java.io.File
-import java.io.FileNotFoundException
 
 class BookSourceActivity : VMBaseActivity<BookSourceViewModel>(R.layout.activity_book_source),
     PopupMenu.OnMenuItemClickListener,
@@ -86,7 +83,8 @@ class BookSourceActivity : VMBaseActivity<BookSourceViewModel>(R.layout.activity
             R.id.menu_import_source_qr -> startActivityForResult<QrCodeActivity>(qrRequestCode)
             R.id.menu_group_manage ->
                 GroupManageDialog().show(supportFragmentManager, "groupManage")
-            R.id.menu_import_source_local -> selectFileSys()
+            R.id.menu_import_source_local -> FilePicker
+                .selectFile(this, importSource, "text/*", arrayOf("txt", "json"))
             R.id.menu_import_source_onLine -> showImportDialog()
         }
         if (item.groupId == R.id.source_group) {
@@ -239,34 +237,6 @@ class BookSourceActivity : VMBaseActivity<BookSourceViewModel>(R.layout.activity
         }.show().applyTint()
     }
 
-    private fun selectFileSys() {
-        try {
-            val intent = Intent(Intent.ACTION_GET_CONTENT)
-            intent.addCategory(Intent.CATEGORY_OPENABLE)
-            intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
-            intent.type = "text/*"//设置类型
-            startActivityForResult(intent, importSource)
-        } catch (e: Exception) {
-            PermissionsCompat.Builder(this)
-                .addPermissions(
-                    Permissions.READ_EXTERNAL_STORAGE,
-                    Permissions.WRITE_EXTERNAL_STORAGE
-                )
-                .rationale(R.string.bg_image_per)
-                .onGranted {
-                    selectFile()
-                }
-                .request()
-        }
-    }
-
-    private fun selectFile() {
-        FileChooserDialog.show(
-            supportFragmentManager, importSource,
-            allowExtensions = arrayOf("txt", "json")
-        )
-    }
-
     override fun upCountView() {
         select_action_bar.upCountView(adapter.getSelection().size, adapter.getActualItemCount())
     }
@@ -338,17 +308,6 @@ class BookSourceActivity : VMBaseActivity<BookSourceViewModel>(R.layout.activity
                                 title_bar.snackbar(msg)
                             }
                         }
-                    } catch (e: FileNotFoundException) {
-                        PermissionsCompat.Builder(this)
-                            .addPermissions(
-                                Permissions.READ_EXTERNAL_STORAGE,
-                                Permissions.WRITE_EXTERNAL_STORAGE
-                            )
-                            .rationale(R.string.bg_image_per)
-                            .onGranted {
-                                selectFileSys()
-                            }
-                            .request()
                     } catch (e: Exception) {
                         toast(e.localizedMessage ?: "ERROR")
                     }
diff --git a/app/src/main/java/io/legado/app/ui/filechooser/FileChooserDialog.kt b/app/src/main/java/io/legado/app/ui/filechooser/FileChooserDialog.kt
index af8cf50f4..f1e6a7bc9 100644
--- a/app/src/main/java/io/legado/app/ui/filechooser/FileChooserDialog.kt
+++ b/app/src/main/java/io/legado/app/ui/filechooser/FileChooserDialog.kt
@@ -42,7 +42,7 @@ class FileChooserDialog : DialogFragment(),
             isShowHomeDir: Boolean = false,
             isShowUpDir: Boolean = true,
             isShowHideDir: Boolean = false,
-            allowExtensions: Array<String?>? = null,
+            allowExtensions: Array<String>? = null,
             menus: Array<String>? = null
         ) {
             FileChooserDialog().apply {
@@ -61,7 +61,7 @@ class FileChooserDialog : DialogFragment(),
         }
     }
 
-    override var allowExtensions: Array<String?>? = null
+    override var allowExtensions: Array<String>? = null
     override val isOnlyListDir: Boolean
         get() = mode == DIRECTORY
     override var isShowHomeDir: Boolean = false
diff --git a/app/src/main/java/io/legado/app/ui/filechooser/FilePicker.kt b/app/src/main/java/io/legado/app/ui/filechooser/FilePicker.kt
index aa3db53c3..0b81368a1 100644
--- a/app/src/main/java/io/legado/app/ui/filechooser/FilePicker.kt
+++ b/app/src/main/java/io/legado/app/ui/filechooser/FilePicker.kt
@@ -94,6 +94,7 @@ object FilePicker {
         activity: BaseActivity,
         requestCode: Int,
         type: String,
+        allowExtensions: Array<String>?,
         default: (() -> Unit)? = null
     ) {
         activity.alert(titleResource = R.string.select_file) {
@@ -125,7 +126,8 @@ object FilePicker {
                                 FileChooserDialog.show(
                                     activity.supportFragmentManager,
                                     requestCode,
-                                    mode = FileChooserDialog.FILE
+                                    mode = FileChooserDialog.FILE,
+                                    allowExtensions = allowExtensions
                                 )
                             }
                             .request()
@@ -139,6 +141,7 @@ object FilePicker {
         fragment: Fragment,
         requestCode: Int,
         type: String,
+        allowExtensions: Array<String>,
         default: (() -> Unit)? = null
     ) {
         fragment.requireContext()
@@ -171,7 +174,8 @@ object FilePicker {
                                     FileChooserDialog.show(
                                         fragment.childFragmentManager,
                                         requestCode,
-                                        mode = FileChooserDialog.FILE
+                                        mode = FileChooserDialog.FILE,
+                                        allowExtensions = allowExtensions
                                     )
                                 }
                                 .request()
diff --git a/app/src/main/java/io/legado/app/ui/filechooser/adapter/FileAdapter.kt b/app/src/main/java/io/legado/app/ui/filechooser/adapter/FileAdapter.kt
index 0fbaafe33..42e34dfb1 100644
--- a/app/src/main/java/io/legado/app/ui/filechooser/adapter/FileAdapter.kt
+++ b/app/src/main/java/io/legado/app/ui/filechooser/adapter/FileAdapter.kt
@@ -122,7 +122,7 @@ class FileAdapter(context: Context, val callBack: CallBack) :
     interface CallBack {
         fun onFileClick(position: Int)
         //允许的扩展名
-        var allowExtensions: Array<String?>?
+        var allowExtensions: Array<String>?
         /**
          * 是否仅仅读取目录
          */
diff --git a/app/src/main/java/io/legado/app/ui/filechooser/utils/FileUtils.kt b/app/src/main/java/io/legado/app/ui/filechooser/utils/FileUtils.kt
index 309dee0a2..e7e2a4805 100644
--- a/app/src/main/java/io/legado/app/ui/filechooser/utils/FileUtils.kt
+++ b/app/src/main/java/io/legado/app/ui/filechooser/utils/FileUtils.kt
@@ -60,7 +60,7 @@ object FileUtils {
     @JvmOverloads
     fun listDirs(
         startDirPath: String,
-        excludeDirs: Array<String?>? = null, @SortType sortType: Int = BY_NAME_ASC
+        excludeDirs: Array<String>? = null, @SortType sortType: Int = BY_NAME_ASC
     ): Array<File?> {
         var excludeDirs1 = excludeDirs
         val dirList = ArrayList<File>()
@@ -76,7 +76,7 @@ object FileUtils {
         })
             ?: return arrayOfNulls(0)
         if (excludeDirs1 == null) {
-            excludeDirs1 = arrayOfNulls(0)
+            excludeDirs1 = arrayOf()
         }
         for (dir in dirs) {
             val file = dir.absoluteFile
@@ -115,7 +115,7 @@ object FileUtils {
     @JvmOverloads
     fun listDirsAndFiles(
         startDirPath: String,
-        allowExtensions: Array<String?>? = null
+        allowExtensions: Array<String>? = null
     ): Array<File?>? {
         val dirs: Array<File?>?
         val files: Array<File?>? = if (allowExtensions == null) {
@@ -189,12 +189,13 @@ object FileUtils {
     /**
      * 列出指定目录下的所有文件
      */
-    fun listFiles(startDirPath: String, allowExtensions: Array<String?>): Array<File?>? {
+    fun listFiles(startDirPath: String, allowExtensions: Array<String>?): Array<File?>? {
         val file = File(startDirPath)
         return file.listFiles { _, name ->
             //返回当前目录所有以某些扩展名结尾的文件
             val extension = getExtension(name)
-            allowExtensions.contentDeepToString().contains(extension)
+            allowExtensions?.contentDeepToString()?.contains(extension) == true
+                    || allowExtensions == null
         }
     }
 
@@ -202,7 +203,10 @@ object FileUtils {
      * 列出指定目录下的所有文件
      */
     fun listFiles(startDirPath: String, allowExtension: String?): Array<File?>? {
-        return listFiles(startDirPath, arrayOf(allowExtension))
+        return if (allowExtension == null)
+            listFiles(startDirPath, allowExtension = null)
+        else
+            listFiles(startDirPath, arrayOf(allowExtension))
     }
 
     /**
diff --git a/app/src/main/java/io/legado/app/ui/replacerule/ReplaceRuleActivity.kt b/app/src/main/java/io/legado/app/ui/replacerule/ReplaceRuleActivity.kt
index 5044e2667..940173bd9 100644
--- a/app/src/main/java/io/legado/app/ui/replacerule/ReplaceRuleActivity.kt
+++ b/app/src/main/java/io/legado/app/ui/replacerule/ReplaceRuleActivity.kt
@@ -20,12 +20,11 @@ import io.legado.app.R
 import io.legado.app.base.VMBaseActivity
 import io.legado.app.data.entities.ReplaceRule
 import io.legado.app.help.ItemTouchCallback
-import io.legado.app.help.permission.Permissions
-import io.legado.app.help.permission.PermissionsCompat
 import io.legado.app.lib.dialogs.*
 import io.legado.app.lib.theme.ATH
 import io.legado.app.lib.theme.primaryTextColor
 import io.legado.app.ui.filechooser.FileChooserDialog
+import io.legado.app.ui.filechooser.FilePicker
 import io.legado.app.ui.replacerule.edit.ReplaceEditDialog
 import io.legado.app.ui.widget.SelectActionBar
 import io.legado.app.ui.widget.recycler.VerticalDivider
@@ -36,7 +35,6 @@ import kotlinx.android.synthetic.main.dialog_edit_text.view.*
 import kotlinx.android.synthetic.main.view_search.*
 import org.jetbrains.anko.toast
 import java.io.File
-import java.io.FileNotFoundException
 
 
 class ReplaceRuleActivity : VMBaseActivity<ReplaceRuleViewModel>(R.layout.activity_replace_rule),
@@ -177,7 +175,8 @@ class ReplaceRuleActivity : VMBaseActivity<ReplaceRuleViewModel>(R.layout.activi
 
             R.id.menu_del_selection -> viewModel.delSelection(adapter.getSelection())
             R.id.menu_import_source_onLine -> showImportDialog()
-            R.id.menu_import_source_local -> selectFileSys()
+            R.id.menu_import_source_local -> FilePicker
+                .selectFile(this, importSource, "text/*", arrayOf("txt", "json"))
         }
         return super.onCompatOptionsItemSelected(item)
     }
@@ -233,34 +232,6 @@ class ReplaceRuleActivity : VMBaseActivity<ReplaceRuleViewModel>(R.layout.activi
         }.show().applyTint()
     }
 
-    private fun selectFileSys() {
-        try {
-            val intent = Intent(Intent.ACTION_GET_CONTENT)
-            intent.addCategory(Intent.CATEGORY_OPENABLE)
-            intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
-            intent.type = "text/*"//设置类型
-            startActivityForResult(intent, importSource)
-        } catch (e: Exception) {
-            PermissionsCompat.Builder(this)
-                .addPermissions(
-                    Permissions.READ_EXTERNAL_STORAGE,
-                    Permissions.WRITE_EXTERNAL_STORAGE
-                )
-                .rationale(R.string.bg_image_per)
-                .onGranted {
-                    selectFile()
-                }
-                .request()
-        }
-    }
-
-    private fun selectFile() {
-        FileChooserDialog.show(
-            supportFragmentManager, importSource,
-            allowExtensions = arrayOf("txt", "json")
-        )
-    }
-
     override fun onFilePicked(requestCode: Int, currentPath: String) {
         if (requestCode == importSource) {
             Snackbar.make(title_bar, R.string.importing, Snackbar.LENGTH_INDEFINITE).show()
@@ -292,17 +263,6 @@ class ReplaceRuleActivity : VMBaseActivity<ReplaceRuleViewModel>(R.layout.activi
                                 title_bar.snackbar(msg)
                             }
                         }
-                    } catch (e: FileNotFoundException) {
-                        PermissionsCompat.Builder(this)
-                            .addPermissions(
-                                Permissions.READ_EXTERNAL_STORAGE,
-                                Permissions.WRITE_EXTERNAL_STORAGE
-                            )
-                            .rationale(R.string.bg_image_per)
-                            .onGranted {
-                                selectFileSys()
-                            }
-                            .request()
                     } catch (e: Exception) {
                         toast(e.localizedMessage ?: "ERROR")
                     }
diff --git a/app/src/main/java/io/legado/app/ui/rss/source/manage/RssSourceActivity.kt b/app/src/main/java/io/legado/app/ui/rss/source/manage/RssSourceActivity.kt
index 22277476e..b26cfe8f7 100644
--- a/app/src/main/java/io/legado/app/ui/rss/source/manage/RssSourceActivity.kt
+++ b/app/src/main/java/io/legado/app/ui/rss/source/manage/RssSourceActivity.kt
@@ -20,12 +20,11 @@ import io.legado.app.R
 import io.legado.app.base.VMBaseActivity
 import io.legado.app.data.entities.RssSource
 import io.legado.app.help.ItemTouchCallback
-import io.legado.app.help.permission.Permissions
-import io.legado.app.help.permission.PermissionsCompat
 import io.legado.app.lib.dialogs.*
 import io.legado.app.lib.theme.ATH
 import io.legado.app.lib.theme.primaryTextColor
 import io.legado.app.ui.filechooser.FileChooserDialog
+import io.legado.app.ui.filechooser.FilePicker
 import io.legado.app.ui.qrcode.QrCodeActivity
 import io.legado.app.ui.rss.source.edit.RssSourceEditActivity
 import io.legado.app.ui.widget.SelectActionBar
@@ -38,7 +37,6 @@ import kotlinx.android.synthetic.main.view_search.*
 import org.jetbrains.anko.startActivity
 import org.jetbrains.anko.startActivityForResult
 import org.jetbrains.anko.toast
-import java.io.FileNotFoundException
 
 
 class RssSourceActivity : VMBaseActivity<RssSourceViewModel>(R.layout.activity_rss_source),
@@ -79,7 +77,8 @@ class RssSourceActivity : VMBaseActivity<RssSourceViewModel>(R.layout.activity_r
     override fun onCompatOptionsItemSelected(item: MenuItem): Boolean {
         when (item.itemId) {
             R.id.menu_add -> startActivity<RssSourceEditActivity>()
-            R.id.menu_import_source_local -> selectFileSys()
+            R.id.menu_import_source_local -> FilePicker
+                .selectFile(this, importSource, "text/*", arrayOf("txt", "json"))
             R.id.menu_import_source_onLine -> showImportDialog()
             R.id.menu_import_source_qr -> startActivityForResult<QrCodeActivity>(qrRequestCode)
             R.id.menu_group_manage -> GroupManageDialog()
@@ -248,33 +247,6 @@ class RssSourceActivity : VMBaseActivity<RssSourceViewModel>(R.layout.activity_r
         }.show().applyTint()
     }
 
-    private fun selectFileSys() {
-        try {
-            val intent = Intent(Intent.ACTION_GET_CONTENT)
-            intent.addCategory(Intent.CATEGORY_OPENABLE)
-            intent.type = "text/*"//设置类型
-            startActivityForResult(intent, importSource)
-        } catch (e: Exception) {
-            PermissionsCompat.Builder(this)
-                .addPermissions(
-                    Permissions.READ_EXTERNAL_STORAGE,
-                    Permissions.WRITE_EXTERNAL_STORAGE
-                )
-                .rationale(R.string.bg_image_per)
-                .onGranted {
-                    selectFile()
-                }
-                .request()
-        }
-    }
-
-    private fun selectFile() {
-        FileChooserDialog.show(
-            supportFragmentManager, importSource,
-            allowExtensions = arrayOf("txt", "json")
-        )
-    }
-
     override fun onFilePicked(requestCode: Int, currentPath: String) {
         if (requestCode == importSource) {
             Snackbar.make(title_bar, R.string.importing, Snackbar.LENGTH_INDEFINITE).show()
@@ -297,17 +269,6 @@ class RssSourceActivity : VMBaseActivity<RssSourceViewModel>(R.layout.activity_r
                                 title_bar.snackbar(msg)
                             }
                         }
-                    } catch (e: FileNotFoundException) {
-                        PermissionsCompat.Builder(this)
-                            .addPermissions(
-                                Permissions.READ_EXTERNAL_STORAGE,
-                                Permissions.WRITE_EXTERNAL_STORAGE
-                            )
-                            .rationale(R.string.bg_image_per)
-                            .onGranted {
-                                selectFileSys()
-                            }
-                            .request()
                     } catch (e: Exception) {
                         toast(e.localizedMessage ?: "ERROR")
                     }
diff --git a/app/src/main/java/io/legado/app/ui/widget/font/FontSelectDialog.kt b/app/src/main/java/io/legado/app/ui/widget/font/FontSelectDialog.kt
index 87d87e8d6..bbeb7f04e 100644
--- a/app/src/main/java/io/legado/app/ui/widget/font/FontSelectDialog.kt
+++ b/app/src/main/java/io/legado/app/ui/widget/font/FontSelectDialog.kt
@@ -23,13 +23,13 @@ import io.legado.app.help.permission.Permissions
 import io.legado.app.help.permission.PermissionsCompat
 import io.legado.app.lib.dialogs.alert
 import io.legado.app.ui.filechooser.FileChooserDialog
+import io.legado.app.ui.filechooser.FilePicker
 import io.legado.app.utils.*
 import kotlinx.android.synthetic.main.dialog_font_select.*
 import kotlinx.coroutines.Dispatchers.IO
 import kotlinx.coroutines.Dispatchers.Main
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
-import org.jetbrains.anko.toast
 import java.io.File
 
 class FontSelectDialog : BaseDialogFragment(),
@@ -107,41 +107,11 @@ class FontSelectDialog : BaseDialogFragment(),
 
     private fun openFolder() {
         launch(Main) {
-            alert {
-                titleResource = R.string.select_folder
-                items(resources.getStringArray(R.array.select_folder).toList()) { _, index ->
-                    when (index) {
-                        0 -> {
-                            val path = "${FileUtils.getSdCardPath()}${File.separator}Fonts"
-                            putPrefString(PreferKey.fontFolder, path)
-                            getFontFilesByPermission(path)
-                        }
-                        1 -> {
-                            try {
-                                val intent = Intent(Intent.ACTION_OPEN_DOCUMENT_TREE)
-                                intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
-                                startActivityForResult(intent, fontFolderRequestCode)
-                            } catch (e: java.lang.Exception) {
-                                e.printStackTrace()
-                                requireContext().toast(e.localizedMessage ?: "ERROR")
-                            }
-                        }
-                        2 -> {
-                            PermissionsCompat.Builder(this@FontSelectDialog)
-                                .addPermissions(*Permissions.Group.STORAGE)
-                                .rationale(R.string.tip_perm_request_storage)
-                                .onGranted {
-                                    FileChooserDialog.show(
-                                        childFragmentManager,
-                                        fontFolderRequestCode,
-                                        mode = FileChooserDialog.DIRECTORY
-                                    )
-                                }
-                                .request()
-                        }
-                    }
-                }
-            }.show()
+            FilePicker.selectFolder(this@FontSelectDialog, fontFolderRequestCode) {
+                val path = "${FileUtils.getSdCardPath()}${File.separator}Fonts"
+                putPrefString(PreferKey.fontFolder, path)
+                getFontFilesByPermission(path)
+            }
         }
     }