How to declare a variable with two possible types
I have two Core Data entities which populate a UITableView with 2 sections, one entity for each section. When the user taps on a table row, they are directed to another view where the data of that row is sent. It is currently implemented like this:
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if (segue.identifier == "editValue") {
let secondViewController = segue.destination as! EditValuesViewController
if send_array_inc.isEmpty {
secondViewController.send_array_exp = send_array_exp
} else if send_array_exp.isEmpty {
secondViewController.send_array_inc = send_array_inc
}
}
}
The Question:
Since there are two entities, there are two possible types (Income and Expenses) for the data being sent into the next view. How can I use that data in the next view with one variable? I am doing the below in ViewDidLoad but the scope of send_array remains within that function. How can I make send_array available outside?
if send_array_inc.isEmpty {
var send_array = [Expenses]()
send_array = send_array_exp
} else if send_array_exp.isEmpty {
var send_array = [Income]()
send_array = send_array_inc
}
I ideally want to do this without creating a separate view for each entity result but I am open to refactor if another solution would be better and realistic. Thank you
swift uitableview core-data scope
asked Nov 23 '18 at 13:57
NoumanNouman
92212
add a comment |
I have two Core Data entities which populate a UITableView with 2 sections, one entity for each section. When the user taps on a table row, they are directed to another view where the data of that row is sent. It is currently implemented like this:
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if (segue.identifier == "editValue") {
let secondViewController = segue.destination as! EditValuesViewController
if send_array_inc.isEmpty {
secondViewController.send_array_exp = send_array_exp
} else if send_array_exp.isEmpty {
secondViewController.send_array_inc = send_array_inc
}
}
}
The Question:
Since there are two entities, there are two possible types (Income and Expenses) for the data being sent into the next view. How can I use that data in the next view with one variable? I am doing the below in ViewDidLoad but the scope of send_array remains within that function. How can I make send_array available outside?
if send_array_inc.isEmpty {
var send_array = [Expenses]()
send_array = send_array_exp
} else if send_array_exp.isEmpty {
var send_array = [Income]()
send_array = send_array_inc
}
I ideally want to do this without creating a separate view for each entity result but I am open to refactor if another solution would be better and realistic. Thank you
swift uitableview core-data scope
asked Nov 23 '18 at 13:57
NoumanNouman
92212
1
Consider using only one entity and adding a type column to differentiate between expenses and income. Another option to consider is to use inheritance in Core Data and to define the common fields that you want to edit in your view controller in the parent entity.
– Mike Taverne
Nov 24 '18 at 0:26
I really like that first idea Mike, Thanks man!!
– Nouman
Nov 24 '18 at 21:19
add a comment |
I have two Core Data entities which populate a UITableView with 2 sections, one entity for each section. When the user taps on a table row, they are directed to another view where the data of that row is sent. It is currently implemented like this:
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if (segue.identifier == "editValue") {
let secondViewController = segue.destination as! EditValuesViewController
if send_array_inc.isEmpty {
secondViewController.send_array_exp = send_array_exp
} else if send_array_exp.isEmpty {
secondViewController.send_array_inc = send_array_inc
}
}
}
The Question:
Since there are two entities, there are two possible types (Income and Expenses) for the data being sent into the next view. How can I use that data in the next view with one variable? I am doing the below in ViewDidLoad but the scope of send_array remains within that function. How can I make send_array available outside?
if send_array_inc.isEmpty {
var send_array = [Expenses]()
send_array = send_array_exp
} else if send_array_exp.isEmpty {
var send_array = [Income]()
send_array = send_array_inc
}
I ideally want to do this without creating a separate view for each entity result but I am open to refactor if another solution would be better and realistic. Thank you
swift uitableview core-data scope
asked Nov 23 '18 at 13:57
NoumanNouman
92212
I have two Core Data entities which populate a UITableView with 2 sections, one entity for each section. When the user taps on a table row, they are directed to another view where the data of that row is sent. It is currently implemented like this:
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if (segue.identifier == "editValue") {
let secondViewController = segue.destination as! EditValuesViewController
if send_array_inc.isEmpty {
secondViewController.send_array_exp = send_array_exp
} else if send_array_exp.isEmpty {
secondViewController.send_array_inc = send_array_inc
}
}
}
The Question:
Since there are two entities, there are two possible types (Income and Expenses) for the data being sent into the next view. How can I use that data in the next view with one variable? I am doing the below in ViewDidLoad but the scope of send_array remains within that function. How can I make send_array available outside?
if send_array_inc.isEmpty {
var send_array = [Expenses]()
send_array = send_array_exp
} else if send_array_exp.isEmpty {
var send_array = [Income]()
send_array = send_array_inc
}
I ideally want to do this without creating a separate view for each entity result but I am open to refactor if another solution would be better and realistic. Thank you
swift uitableview core-data scope
swift uitableview core-data scope
asked Nov 23 '18 at 13:57
NoumanNouman
92212
asked Nov 23 '18 at 13:57
NoumanNouman
92212
edited Nov 23 '18 at 14:03
Nouman
asked Nov 23 '18 at 13:57
NoumanNouman
92212
asked Nov 23 '18 at 13:57
NoumanNouman
92212
asked Nov 23 '18 at 13:57
NoumanNouman
92212
92212
1
Consider using only one entity and adding a type column to differentiate between expenses and income. Another option to consider is to use inheritance in Core Data and to define the common fields that you want to edit in your view controller in the parent entity.
– Mike Taverne
Nov 24 '18 at 0:26
I really like that first idea Mike, Thanks man!!
– Nouman
Nov 24 '18 at 21:19
add a comment |
1
Consider using only one entity and adding a type column to differentiate between expenses and income. Another option to consider is to use inheritance in Core Data and to define the common fields that you want to edit in your view controller in the parent entity.
– Mike Taverne
Nov 24 '18 at 0:26
I really like that first idea Mike, Thanks man!!
– Nouman
Nov 24 '18 at 21:19
1
1
Consider using only one entity and adding a type column to differentiate between expenses and income. Another option to consider is to use inheritance in Core Data and to define the common fields that you want to edit in your view controller in the parent entity.
– Mike Taverne
Nov 24 '18 at 0:26
Consider using only one entity and adding a type column to differentiate between expenses and income. Another option to consider is to use inheritance in Core Data and to define the common fields that you want to edit in your view controller in the parent entity.
– Mike Taverne
Nov 24 '18 at 0:26
I really like that first idea Mike, Thanks man!!
– Nouman
Nov 24 '18 at 21:19
I really like that first idea Mike, Thanks man!!
– Nouman
Nov 24 '18 at 21:19
add a comment |
1 Answer
1
active
oldest
votes
Make your two types of data objects conform to a shared protocol. Make the destination view controller's send_array be an object conforming to that protocol.
In your EditValuesViewController's code, interrogate the send_array to figure out which type of data object was passed in.
Edit:
Define a protocol
@protocol dataArrayProtocol {
var dataArray: Array
}
Define 2 structs that conform to that protocol
struct ExpensesArrayStruct: dataArrayProtocol {
var dataArray: [Expenses]
}
struct IncomeArrayStruct: dataArrayProtocol {
var dataArray: [Income]
}
give your EditValuesViewController a property that conforms to that protocol
class EditValuesViewController: UIViewController {
var dataArrayStruct: dataArrayProtocol
}
And your prepare(for:sender) method
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if (segue.identifier == "editValue") {
let secondViewController = segue.destination as! EditValuesViewController
if send_array_inc.isEmpty {
secondViewController.dataArrayStruct = ExpensesArrayStruct(dataArray: send_array_exp)
} else if send_array_exp.isEmpty {
secondViewController.dataArrayStruct = IncomeArrayStruct(dataArray: send_array_inc)
}
}
}
And to handle the data:
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
if let expensesStruct = dataArrayStruct as? ExpensesArrayStruct {
//deal with expenses array
} else if let incomeStruct = dataArrayStruct as? IncomeArrayStruct {
//deal with income array
}
}
Note that I banged this code out in the SO editor and have not tried to compile it. I may have made some minor errors. It should give you the idea though.
answered Nov 23 '18 at 14:05
Duncan CDuncan C
92.4k13114196
1
It's harder to make generic collections like arrays conform to a shared protocol. You could wrap your array in a struct and make the struct conform to your protocol.
– Duncan C
Nov 23 '18 at 14:20
add a comment |
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1 Answer
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1 Answer
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oldest
votes
Make your two types of data objects conform to a shared protocol. Make the destination view controller's send_array be an object conforming to that protocol.
In your EditValuesViewController's code, interrogate the send_array to figure out which type of data object was passed in.
Edit:
Define a protocol
@protocol dataArrayProtocol {
var dataArray: Array
}
Define 2 structs that conform to that protocol
struct ExpensesArrayStruct: dataArrayProtocol {
var dataArray: [Expenses]
}
struct IncomeArrayStruct: dataArrayProtocol {
var dataArray: [Income]
}
give your EditValuesViewController a property that conforms to that protocol
class EditValuesViewController: UIViewController {
var dataArrayStruct: dataArrayProtocol
}
And your prepare(for:sender) method
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if (segue.identifier == "editValue") {
let secondViewController = segue.destination as! EditValuesViewController
if send_array_inc.isEmpty {
secondViewController.dataArrayStruct = ExpensesArrayStruct(dataArray: send_array_exp)
} else if send_array_exp.isEmpty {
secondViewController.dataArrayStruct = IncomeArrayStruct(dataArray: send_array_inc)
}
}
}
And to handle the data:
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
if let expensesStruct = dataArrayStruct as? ExpensesArrayStruct {
//deal with expenses array
} else if let incomeStruct = dataArrayStruct as? IncomeArrayStruct {
//deal with income array
}
}
Note that I banged this code out in the SO editor and have not tried to compile it. I may have made some minor errors. It should give you the idea though.
answered Nov 23 '18 at 14:05
Duncan CDuncan C
92.4k13114196
1
It's harder to make generic collections like arrays conform to a shared protocol. You could wrap your array in a struct and make the struct conform to your protocol.
– Duncan C
Nov 23 '18 at 14:20
add a comment |
Make your two types of data objects conform to a shared protocol. Make the destination view controller's send_array be an object conforming to that protocol.
In your EditValuesViewController's code, interrogate the send_array to figure out which type of data object was passed in.
Edit:
Define a protocol
@protocol dataArrayProtocol {
var dataArray: Array
}
Define 2 structs that conform to that protocol
struct ExpensesArrayStruct: dataArrayProtocol {
var dataArray: [Expenses]
}
struct IncomeArrayStruct: dataArrayProtocol {
var dataArray: [Income]
}
give your EditValuesViewController a property that conforms to that protocol
class EditValuesViewController: UIViewController {
var dataArrayStruct: dataArrayProtocol
}
And your prepare(for:sender) method
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if (segue.identifier == "editValue") {
let secondViewController = segue.destination as! EditValuesViewController
if send_array_inc.isEmpty {
secondViewController.dataArrayStruct = ExpensesArrayStruct(dataArray: send_array_exp)
} else if send_array_exp.isEmpty {
secondViewController.dataArrayStruct = IncomeArrayStruct(dataArray: send_array_inc)
}
}
}
And to handle the data:
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
if let expensesStruct = dataArrayStruct as? ExpensesArrayStruct {
//deal with expenses array
} else if let incomeStruct = dataArrayStruct as? IncomeArrayStruct {
//deal with income array
}
}
Note that I banged this code out in the SO editor and have not tried to compile it. I may have made some minor errors. It should give you the idea though.
answered Nov 23 '18 at 14:05
Duncan CDuncan C
92.4k13114196
1
It's harder to make generic collections like arrays conform to a shared protocol. You could wrap your array in a struct and make the struct conform to your protocol.
– Duncan C
Nov 23 '18 at 14:20
add a comment |
Make your two types of data objects conform to a shared protocol. Make the destination view controller's send_array be an object conforming to that protocol.
In your EditValuesViewController's code, interrogate the send_array to figure out which type of data object was passed in.
Edit:
Define a protocol
@protocol dataArrayProtocol {
var dataArray: Array
}
Define 2 structs that conform to that protocol
struct ExpensesArrayStruct: dataArrayProtocol {
var dataArray: [Expenses]
}
struct IncomeArrayStruct: dataArrayProtocol {
var dataArray: [Income]
}
give your EditValuesViewController a property that conforms to that protocol
class EditValuesViewController: UIViewController {
var dataArrayStruct: dataArrayProtocol
}
And your prepare(for:sender) method
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if (segue.identifier == "editValue") {
let secondViewController = segue.destination as! EditValuesViewController
if send_array_inc.isEmpty {
secondViewController.dataArrayStruct = ExpensesArrayStruct(dataArray: send_array_exp)
} else if send_array_exp.isEmpty {
secondViewController.dataArrayStruct = IncomeArrayStruct(dataArray: send_array_inc)
}
}
}
And to handle the data:
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
if let expensesStruct = dataArrayStruct as? ExpensesArrayStruct {
//deal with expenses array
} else if let incomeStruct = dataArrayStruct as? IncomeArrayStruct {
//deal with income array
}
}
Note that I banged this code out in the SO editor and have not tried to compile it. I may have made some minor errors. It should give you the idea though.
answered Nov 23 '18 at 14:05
Duncan CDuncan C
92.4k13114196
Make your two types of data objects conform to a shared protocol. Make the destination view controller's send_array be an object conforming to that protocol.
In your EditValuesViewController's code, interrogate the send_array to figure out which type of data object was passed in.
Edit:
Define a protocol
@protocol dataArrayProtocol {
var dataArray: Array
}
Define 2 structs that conform to that protocol
struct ExpensesArrayStruct: dataArrayProtocol {
var dataArray: [Expenses]
}
struct IncomeArrayStruct: dataArrayProtocol {
var dataArray: [Income]
}
give your EditValuesViewController a property that conforms to that protocol
class EditValuesViewController: UIViewController {
var dataArrayStruct: dataArrayProtocol
}
And your prepare(for:sender) method
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if (segue.identifier == "editValue") {
let secondViewController = segue.destination as! EditValuesViewController
if send_array_inc.isEmpty {
secondViewController.dataArrayStruct = ExpensesArrayStruct(dataArray: send_array_exp)
} else if send_array_exp.isEmpty {
secondViewController.dataArrayStruct = IncomeArrayStruct(dataArray: send_array_inc)
}
}
}
And to handle the data:
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
if let expensesStruct = dataArrayStruct as? ExpensesArrayStruct {
//deal with expenses array
} else if let incomeStruct = dataArrayStruct as? IncomeArrayStruct {
//deal with income array
}
}
Note that I banged this code out in the SO editor and have not tried to compile it. I may have made some minor errors. It should give you the idea though.
answered Nov 23 '18 at 14:05
Duncan CDuncan C
92.4k13114196
edited Nov 23 '18 at 14:31
answered Nov 23 '18 at 14:05
Duncan CDuncan C
92.4k13114196
answered Nov 23 '18 at 14:05
Duncan CDuncan C
92.4k13114196
answered Nov 23 '18 at 14:05
Duncan CDuncan C
92.4k13114196
92.4k13114196
1
It's harder to make generic collections like arrays conform to a shared protocol. You could wrap your array in a struct and make the struct conform to your protocol.
– Duncan C
Nov 23 '18 at 14:20
add a comment |
1
It's harder to make generic collections like arrays conform to a shared protocol. You could wrap your array in a struct and make the struct conform to your protocol.
– Duncan C
Nov 23 '18 at 14:20
1
1
It's harder to make generic collections like arrays conform to a shared protocol. You could wrap your array in a struct and make the struct conform to your protocol.
– Duncan C
Nov 23 '18 at 14:20
It's harder to make generic collections like arrays conform to a shared protocol. You could wrap your array in a struct and make the struct conform to your protocol.
– Duncan C
Nov 23 '18 at 14:20
add a comment |
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1
Consider using only one entity and adding a type column to differentiate between expenses and income. Another option to consider is to use inheritance in Core Data and to define the common fields that you want to edit in your view controller in the parent entity.
– Mike Taverne
Nov 24 '18 at 0:26
I really like that first idea Mike, Thanks man!!
– Nouman
Nov 24 '18 at 21:19