Hi,

I am trying to do something similar to how Parse arranges data sets with different types in a collection and I am having trouble with uploading UIImage file. I am confused with the guide and API reference and don't quite understand what they meant. I am coding in Swift 2 with Xcode 7.2.1 and KinveyKit 1.40.7.

My first code:

class Image : NSObject {    //all NSObjects in Kinvey implicitly implement KCSPersistable
    var entityId: String? //Kinvey entity _id
    var image: UIImage?
    var senderUsername: String?
    var recipientUsername: String?
    
    override func hostToKinveyPropertyMapping() -> [NSObject : AnyObject]! {
        return [
            "entityId" : KCSEntityKeyId, //the required _id field
            "image" : "image",
            "senderUsername" : "senderUsername",
            "recipientUsername" : "recipientUsername"
        ]
    }
}

KCSAppdataStore successfully saves the 3 entities, except the UIImage. The "Data Store" guide says that UIImage is an accepted data type but with the following note: "If there is a UIImage property and the object is saved with a KCSLinkedAppdataStore a file will be created and linked to the entity. See Automatically Linking Images for more information."

Does that mean that KCSLinkedAppdataStore is required for UIImage? The note says that 'IF' it is used but doesn't say it's required.

The 'KCSLinkedAppdataStore Class Reference' says that 'To make use of this, have an entity map a UIImage property to the KCSFileStoreCollectionName in - [KCSPersistable hostToKinveyPropertyMapping], and save that entity.'

So with that, I modified my class to:

class Image : NSObject {    //all NSObjects in Kinvey implicitly implement KCSPersistable
    var entityId: String? //Kinvey entity _id
    var image: UIImage?
    var senderUsername: String?
    var recipientUsername: String?
    
    override func hostToKinveyPropertyMapping() -> [NSObject : AnyObject]! {
        return [
            "entityId" : KCSEntityKeyId, //the required _id field
            "image" : KCSFileStoreCollectionName,
            "senderUsername" : "senderUsername",
            "recipientUsername" : "recipientUsername"
        ]
    }
    
    func kinveyPropertyToCollectionMapping() -> [NSObject : AnyObject]! {

        return [
            "image" : "image"
        ]
    }
    
}

 and change the saving method to:

var imageToSend = KCSLinkedAppdataStore.storeWithOptions([
            KCSStoreKeyCollectionName : "Images",
            KCSStoreKeyCollectionTemplateClass : Image.self
            ])
    
        
        let imageSendingData = Image()
        imageSendingData.image = UIImage(data: UIImageJPEGRepresentation(image, 0.1)!)
        imageSendingData.senderUsername = KCSUser.activeUser().username
        imageSendingData.recipientUsername = userArray[activeRecipient]
        
        imageToSend.saveObject(imageSendingData, withCompletionBlock: { (objectsOrNil, errorOrNil) -> Void in
            
            if errorOrNil != nil {
                
                print("Error saving image: \(errorOrNil)")
                
            } else {
                
                print("Save image successful")
                
            }
            
            }, withProgressBlock: nil)

 Still doesn't work. Then changing the class to:

class Image : NSObject {    //all NSObjects in Kinvey implicitly implement KCSPersistable
    var entityId: String? //Kinvey entity _id
    var image: UIImage?
    var senderUsername: String?
    var recipientUsername: String?
    
    override func hostToKinveyPropertyMapping() -> [NSObject : AnyObject]! {
        return [
            "entityId" : KCSEntityKeyId, //the required _id field
            "image" : "image",
            "senderUsername" : "senderUsername",
            "recipientUsername" : "recipientUsername"
        ]
    }
    
    func kinveyPropertyToCollectionMapping() -> [NSObject : AnyObject]!{
        
        return [
            "image" : KCSFileStoreCollectionName
        ]
    }
    
}

 Now the collection has a new column called '_blob' but the value is null.

What is the correct way of uploading images in a collection?

Thanks.