如何從集合中獲取對象，將其更新並保存？

Question

對不起，模糊的標題。爲了讓我保存一個特定的對象，我需要查詢它，它返回一個集合。編輯後如何保存該集合？

任何幫助表示讚賞。

func joinGroup() { 

    var group = Groups() 


    backendless.initApp(APP_ID, secret:SECRET_KEY, version:VERSION_NUM) 
    self.backendless.userService.getPersistentUser() 
    let user = self.backendless.userService.currentUser 

    let whereClause = "UsersInGroup.objectId = '\(user.objectId)'" 
    let dataQuery = BackendlessDataQuery() 
    dataQuery.whereClause = whereClause 

    var error: Fault? 
    var dataStore = self.backendless.persistenceService.find(Groups.ofClass(), 
     dataQuery:dataQuery) as BackendlessCollection 

    for joiningroup in dataStore.data as! [Groups] { 

     joiningroup.UsersInGroup.append(user) 



    } 

這裏的對象是如何保存

func createGroup() { 


    let groups = self.backendless.persistenceService.of(Groups().ofClass()) 

    backendless.initApp(APP_ID, secret:SECRET_KEY, version:VERSION_NUM) 
    self.backendless.userService.getPersistentUser() 
    let user = self.backendless.userService.currentUser 

    var newGroup = Groups() 
    newGroup.groupName = "FromClient" 
    newGroup.ownerId = user.objectId 
    newGroup.UsersInGroup.append(user) 

    var error: Fault? 
    newGroup = groups.save(newGroup) as! Groups 
    if error == nil { 
     print("Created group: \(newGroup.groupName)") 
    } 
    else { 
     print("Server reported an error: \(error)") 
    } 



} 

Answer 1

func joinGroup() { 

     self.backendless.userService.getPersistentUser() 
     let user = self.backendless.userService.currentUser 


      let dataStore = backendless.data.of(Groups.ofClass()) 
     dataStore.findID(
         "A772D4AB-BCB6-1C2E-FFE9-C436C65E3200", 
         response: { (result: AnyObject!) -> Void in 
          let foundContact = result as! Groups 
          let groupJoining = foundContact 
          groupJoining.UsersInGroup.append(user) 
          dataStore.save(
       groupJoining, 
       response: { (result: AnyObject!) -> Void in 
        let savedContact = result as! Groups 
        print("Contact has been saved: \(savedContact.objectId)") 

       }, 
       error: { (fault: Fault!) -> Void in 
        print("Server reported an error (1): \(fault)") 
      }) 


          print("Contact has been found: \(foundContact.objectId)") 
         }, 
         error: { (fault: Fault!) -> Void in 
          print("Server reported an error (2): \(fault)") 
        }) 




    } 

Answer 2

您只需保存父對象（前提是你之前已經加載的子集），和孩子集合將自動與您添加新對象保存到它。