我寫了兩個分開的函數fetchRecords
和displayRecords
寫入Appdelegate
類。 fetchRecords
函數將從實體中提取所有記錄,並且它工作正常。 displayRecords
函數接受來自fetchRecords
函數的返回值,並逐個打印所有記錄。
我有一個視圖控制器,它調用這兩個函數來完成所需的任務。我的問題是result.count
displayRecords
顯示提取記錄中可用記錄的總數。在逐一打印記錄時,值爲零。核心數據 - NSManagedObject返回無
override func viewDidLoad() {
super.viewDidLoad()
let fetchedRecords = AppDelegate().fetchRecords(fromEntity: "Dashboard")
AppDelegate().displayRecords(fromFetchedRecords: fetchedRecords)
}
這裏是寫在AppDelegate類
func fetchRecords(fromEntity entity:String) -> Array<AnyObject> {
var fetchedResult:Array<AnyObject> = []
let fetchRequest = NSFetchRequest()
let entityDescription = NSEntityDescription.entityForName(entity, inManagedObjectContext: self.managedObjectContext)!
fetchRequest.entity = entityDescription
do{
fetchedResult = try self.managedObjectContext.executeFetchRequest(fetchRequest)
}catch{
let fetchError = error as NSError?
print(fetchError!)
}
return fetchedResult
}
func displayRecords(fromFetchedRecords result:Array<AnyObject>) {
print("Total records:\(result.count)")
if (result.count > 0) {
for data in result {
let dashboard = data as! NSManagedObject
print("Value: \(dashboard.valueForKey("count"))")
}
}
}
的fetchRecords
和displayRecords
功能添加我的數據模型這裏
我也將分享數據插入代碼。
func saveDashBoardData(dictionary: Dictionary<String, String>) {
print(NSFileManager.defaultManager().URLsForDirectory(.DocumentDirectory, inDomains: .UserDomainMask))
//Create Manage Object
let entityDescription: NSEntityDescription = NSEntityDescription.entityForName("Dashboard", inManagedObjectContext: self.managedObjectContext)!
for data in dictionary {
let dashboardObject = Dashboard(entity: entityDescription,insertIntoManagedObjectContext: self.managedObjectContext)
dashboardObject.type = data.0
dashboardObject.count = data.1
do {
try self.managedObjectContext.save()
print("Data saved succesfully")
}
catch {
print(error)
}
}
}
你能告訴我你的coredata模型項目@sindhu JA –
我有共同的問題的數據模型。請找到它 –
我無法得到你想說的話@vadian –