fix readFolder

PickerFileProvider/FileProviderEnumerator.swift

@@ -155,7 +155,7 @@ class FileProviderEnumerator: NSObject, NSFileProviderEnumerator {
             let ocNetworking = OCnetworking.init(delegate: nil, metadataNet: nil, withUser: providerData.accountUser, withUserID: providerData.accountUserID, withPassword: providerData.accountPassword, withUrl: providerData.accountUrl)
             ocNetworking?.readFile(fileName, serverUrl: serverUrlForFileName, account: providerData.account, success: { (metadata) in
                 
-                if self.providerData.listServerUrlEtag[serverUrl] == nil || self.providerData.listServerUrlEtag[serverUrl] != metadata!.etag {
+                if self.providerData.listServerUrlEtag[serverUrl] == nil || self.providerData.listServerUrlEtag[serverUrl] != metadata!.etag || metadatasFromDB == nil {
                     
                     ocNetworking?.readFolder(serverUrl, depth: "1", account: self.providerData.account, success: { (metadatas, metadataFolder, directoryID) in