how to delete row from coredata (Entity) ios swift - ios

Question

i am new to CORE DATA in my app i am using coredata.
i just stored data in my core data. my entity name is "FEED" and i have a rows with name "title", "id " , "link" ,"desc" so now i want to delete perticular row on based on "id". so how can i do this?
Here is my code,
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell : MessageMusicCell = tableView.dequeueReusableCellWithIdentifier("MessageMusicCell") as! MessageMusicCell
cell.pinButton.tag = indexPath.row
cell.pinButton.addTarget(self, action: #selector(MessageViewController.buttonDeletePressed(_:)), forControlEvents: UIControlEvents.TouchUpInside)
cell.selectionStyle = .None
person = people[indexPath.row]
cell.lbl_title_msg_music.text = person!.valueForKey("title") as? String
cell.img_message_music.image = UIImage(named: "PlaceHolder")
cell.desc_msg_music.text = person!.valueForKey("desc") as? String
return cell
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
print(people.count)
return people.count
}
func buttonDeletePressed(sender:UIButton) {
}
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
let cell : MessageMusicCell = tableView.dequeueReusableCellWithIdentifier("MessageMusicCell") as! MessageMusicCell
}
so how can i do this?

Answer 1

Try Like this,
func buttonDeletePressed(sender:UIButton) {
let appDel:AppDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
let context:NSManagedObjectContext = appDel.managedObjectContext
let index = sender.tag
context.deleteObject(people[index] as NSManagedObject)
people.removeAtIndex(index)
let _ : NSError! = nil
do {
try context.save()
self.tableView.reloadData()
} catch {
print("error : \(error)")
}
}
Hope this will help you.

Answer 2

func deleteFeed(id:String)
{
let appDelegate =
UIApplication.sharedApplication().delegate as? AppDelegate
let managedContext = appDelegate?.managedObjectContext
let fetchRequest = NSFetchRequest(entityName:"FEED")
fetchRequest.predicate = NSPredicate(format: "id = %#", "\(id)")
do
{
let fetchedResults = try managedContext!.executeFetchRequest(fetchRequest) as? [NSManagedObject]
for entity in fetchedResults! {
managedContext?.deleteObject(entity)
}
}
catch _ {
print("Could not delete")
}
}
Now you can call this function and pass the id whatever you want to delete
func buttonDeletePressed(sender:UIButton){
deleteFeed("1")
}

Answer 3

You can delete data like,
let appDel:AppDelegate = UIApplication.sharedApplication().delegate as AppDelegate
let context:NSManagedObjectContext = appDel.managedObjectContext!
context.deleteObject(myData[indexPath.row] as NSManagedObject)
myData.removeAtIndex(indexPath.row)
context.save(nil)
this is done from commitEditingStyle so here used indexPath.row. You can pass your id if you want to delete data from other place. If you want to delete data from tableview then you should implement commitEditingStyle and delete data like mentioned above.
Hope this will help :)

Answer 4

override func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {
switch editingStyle {
case .Delete:
// remove the deleted item from the model
let appDel: AppDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
let context: NSManagedObjectContext = appDel.managedObjectContext
context.deleteObject(people[indexPath.row] )
people.removeAtIndex(indexPath.row)
do {
try context.save()
} catch _ {
}
// remove the deleted item from the `UITableView`
self.tableView.deleteRowsAtIndexPaths([indexPath], withRowAnimation: .Fade)
default:
return
}
}
Hope this could be of some help!