How to persist tableview rows? - ios

Question

I am creating an ios app that will show me a user specific set of tasks everyday that i click to delete to show its done. I save the tasks in core data, and just delete the tableview row on click. I dont delete the data in coredata as its userdefined and need to reload it everyday. I use a newDay() function to decide to load data from coredata if the app is opened on a new day. What should i do to remember which all tasks have been done for the day? Do i need to create another enitity to remember which all tasks are completed or is there an simpler way?
var tasks: [NSManagedObject] = []
let defaults = UserDefaults.standard
var calender = Calendar.current
override func viewDidLoad() {
super.viewDidLoad()
title = "DailyTasker"
navigationItem.leftBarButtonItem = editButtonItem
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
let checkDate = newDay()
if checkDate{
//1
guard let appDelegate =
UIApplication.shared.delegate as? AppDelegate else {
return
}
let managedContext =
appDelegate.persistentContainer.viewContext
//2
let fetchRequest =
NSFetchRequest<NSManagedObject>(entityName: "Task")
//3
do {
tasks = try managedContext.fetch(fetchRequest)
defaults.set(Date(), forKey: "LastRun")
} catch let error as NSError {
print("Could not fetch. \(error), \(error.userInfo)")
}
}
}
func newDay() -> Bool{
if let lastRun = defaults.object(forKey: "LastRun") as? Date{
if !calender.isDateInToday(lastRun){
return true
} else {
return false
}
} else {
return true
}
}
#IBAction func addName(_ sender: UIBarButtonItem) {
let alert = UIAlertController(title: "New Task",
message: "Add a new task",
preferredStyle: .alert)
let saveAction = UIAlertAction(title: "Save",
style: .default) {
[unowned self] action in
guard let textField = alert.textFields?.first,
let nameToSave = textField.text else {
return
}
self.save(name: nameToSave)
self.tableView.reloadData()
}
let cancelAction = UIAlertAction(title: "Cancel",
style: .default)
alert.addTextField()
alert.addAction(saveAction)
alert.addAction(cancelAction)
present(alert, animated: true)
}
func save(name: String) {
guard let appDelegate =
UIApplication.shared.delegate as? AppDelegate else {
return
}
// 1
let managedContext =
appDelegate.persistentContainer.viewContext
// 2
let entity =
NSEntityDescription.entity(forEntityName: "Task",
in: managedContext)!
let task = NSManagedObject(entity: entity,
insertInto: managedContext)
// 3
task.setValue(name, forKeyPath: "name")
// 4
do {
try managedContext.save()
tasks.append(task)
} catch let error as NSError {
print("Could not save. \(error), \(error.userInfo)")
}
}
// MARK: - Table view data source
override func numberOfSections(in tableView: UITableView) -> Int {
// #warning Incomplete implementation, return the number of sections
return 1
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
// #warning Incomplete implementation, return the number of rows
return tasks.count
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let task = tasks[indexPath.row]
let cell = tableView.dequeueReusableCell(withIdentifier: "TaskerCell", for: indexPath)
cell.textLabel?.text = task.value(forKeyPath: "name") as? String
return cell
}
// Override to support editing the table view.
override func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCellEditingStyle, forRowAt indexPath: IndexPath) {
if editingStyle == .delete {
// Delete the row from the data source
tasks.remove(at: indexPath.row)
tableView.deleteRows(at: [indexPath], with: .fade)
} else if editingStyle == .insert {
}
}
override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
tasks.remove(at: indexPath.row)
tableView.deleteRows(at: [indexPath], with: .fade)
}
}

Answer 1

You could add a date attribute to your task and name it lastDonefor instance. Then you set that to current date time when a task is done and also use a predicate when fetching task instances so you only get those not done today.
task.lastDone = Date()
I am not sure how you define "today" but this question should help you create a predicate that properly filters your task although you might also want to include tasks where lastDone is null.

Answer 2

I am not sure Why you can't delete the data. Is it due to specifications.
If not then, when you save your task in coredata simply assign it with a unique Identifer(id) and then you can create your own data stack Method to delete the specific task.
You can create a data Model Class or struct for the task example
class TaskData {
var id: Int!
var task: String!
init(id: Int, task: String) {
self.id = id
self.task = task
}
}
Save task as this dataClass into coreData.
When you delete the row at that time captue the Task Id and delete it from coreDataStack.
A good way will be to create a TaskManager Singelton class to handle all the core data Methods.