How do I go about getting an object out of a collection, updating it and saving it?

Question

Sorry for the ambiguous title. In order for me to save a specific object I need to query it, which returns a collection. How do I save that collection after I've edited it?

Any help appreciated.

    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)



    }

Here's how objects are saved

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)")
    }



}

score 0 · Answer 1 · answered Mar 16 '16 at 20:43

0

You can just save a parent object (provided you have loaded the child collection before), and the child collection will automatically be saved with your new object added to it.

answered Mar 16 '16 at 20:43

Scadge

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score 0 · Accepted Answer · answered Mar 17 '16 at 07:21

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)")
                    })




    }

How do I go about getting an object out of a collection, updating it and saving it?

2 Answers2