store custom folder order in shared prefs

app/src/main/kotlin/com/simplemobiletools/gallery/pro/adapters/DirectoryAdapter.kt

@@ -175,6 +175,9 @@ class DirectoryAdapter(activity: BaseSimpleActivity, var dirs: ArrayList<Directo
     override fun onActionModeDestroyed() {
         if (isChangingOrder) {
             notifyDataSetChanged()
+
+            val reorderedFoldersList = dirs.map { it.path }
+            config.customFoldersOrder = TextUtils.join("|||", reorderedFoldersList)
         }
 
         isChangingOrder = false

app/src/main/kotlin/com/simplemobiletools/gallery/pro/helpers/Config.kt

@@ -515,4 +515,8 @@ class Config(context: Context) : BaseConfig(context) {
     var fileRoundedCorners: Boolean
         get() = prefs.getBoolean(FILE_ROUNDED_CORNERS, false)
         set(fileRoundedCorners) = prefs.edit().putBoolean(FILE_ROUNDED_CORNERS, fileRoundedCorners).apply()
+
+    var customFoldersOrder: String
+        get() = prefs.getString(CUSTOM_FOLDERS_ORDER, "")!!
+        set(customFoldersOrder) = prefs.edit().putString(CUSTOM_FOLDERS_ORDER, customFoldersOrder).apply()
 }

app/src/main/kotlin/com/simplemobiletools/gallery/pro/helpers/Constants.kt

@@ -88,6 +88,7 @@ const val FOLDER_MEDIA_COUNT = "folder_media_count"
 const val LIMIT_FOLDER_TITLE = "folder_limit_title"
 const val THUMBNAIL_SPACING = "thumbnail_spacing"
 const val FILE_ROUNDED_CORNERS = "file_rounded_corners"
+const val CUSTOM_FOLDERS_ORDER = "custom_folders_order"
 
 // slideshow
 const val SLIDESHOW_INTERVAL = "slideshow_interval"