Updating uiTableViewCell from data model after intial load
I'm very beginner in iOS development, so this problem may look trivial. I searched and could not find any questions about this problem. But I wonder what is correct approach of updating custom cells of a UITableView when you change your data model at run time after initial loading of cells from data model. From change, I mean data entry change, not adding or removing data.
Here is an example. Let's say that I have these DataModel and DataModelCell as follows:
class DataModelView : UITableViewCell {
@IBOutlet weak var mainLabel: UILabel!
}
class DataModel {
var title: String = "" {
didSet {
// which cell this entry is connected to?
}
}
}
...
items: [DataModel] =
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "DataModelView", for: indexPath)
cell.mainLabel?.text = items[indexPath.item].title
// addition line for each approach
// approach 1:
// items[indexPath.item].view = cell
// approach 2:
// items[indexPath.item].viewIndexPath = indexPath
return cell
}
My problem is that when I changed title of one of cells in my data model at run time, I like to update corresponding cell in UI. I like to know what is the best approach to make a relationship between data model'd entry and cell in UITableView.
There are 3 different approaches that comes to my mind. I want to know if they are correct or not or if there is any better method:
1st approach: a weak pointer to cell in my data entry like this:
class DataModel {
weak var view: DataModelView?
var title: String = "" {
didSet {
view?.mainLabel?.text = title
}
}
}
2nd approach: keep IndexPath of cell in my data entry like this:
class DataModel {
var viewIndexPath: IndexPath?
var title: String = "" {
didSet {
// call delegate to controller and ask to update cell for viewIndexPath
}
}
}
3rd approach: don't keep anything which corresponds to cell in data entry:
class DataModel {
var title: String = "" {
didSet {
// call delegate to controller and ask to find and update cell for self
}
}
}
In first 2 approaches, I keep relationship between cell and data model in my data model. In 3rd approach, I need to keep this relationship in controller.
Are all these approaches correct(especially first one)? Which one do you suggest? and What is best approach generally?
I have seen that people keep a pointer to data model in their view in order to update data model from view. I wonder if it is correct in the other way too or not(1st approach).
ios ios-mvc
asked Dec 28 '18 at 10:56
AfshinAfshin
3,0011624
|
show 5 more comments
I'm very beginner in iOS development, so this problem may look trivial. I searched and could not find any questions about this problem. But I wonder what is correct approach of updating custom cells of a UITableView when you change your data model at run time after initial loading of cells from data model. From change, I mean data entry change, not adding or removing data.
Here is an example. Let's say that I have these DataModel and DataModelCell as follows:
class DataModelView : UITableViewCell {
@IBOutlet weak var mainLabel: UILabel!
}
class DataModel {
var title: String = "" {
didSet {
// which cell this entry is connected to?
}
}
}
...
items: [DataModel] =
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "DataModelView", for: indexPath)
cell.mainLabel?.text = items[indexPath.item].title
// addition line for each approach
// approach 1:
// items[indexPath.item].view = cell
// approach 2:
// items[indexPath.item].viewIndexPath = indexPath
return cell
}
My problem is that when I changed title of one of cells in my data model at run time, I like to update corresponding cell in UI. I like to know what is the best approach to make a relationship between data model'd entry and cell in UITableView.
There are 3 different approaches that comes to my mind. I want to know if they are correct or not or if there is any better method:
1st approach: a weak pointer to cell in my data entry like this:
class DataModel {
weak var view: DataModelView?
var title: String = "" {
didSet {
view?.mainLabel?.text = title
}
}
}
2nd approach: keep IndexPath of cell in my data entry like this:
class DataModel {
var viewIndexPath: IndexPath?
var title: String = "" {
didSet {
// call delegate to controller and ask to update cell for viewIndexPath
}
}
}
3rd approach: don't keep anything which corresponds to cell in data entry:
class DataModel {
var title: String = "" {
didSet {
// call delegate to controller and ask to find and update cell for self
}
}
}
In first 2 approaches, I keep relationship between cell and data model in my data model. In 3rd approach, I need to keep this relationship in controller.
Are all these approaches correct(especially first one)? Which one do you suggest? and What is best approach generally?
I have seen that people keep a pointer to data model in their view in order to update data model from view. I wonder if it is correct in the other way too or not(1st approach).
ios ios-mvc
asked Dec 28 '18 at 10:56
AfshinAfshin
3,0011624
please show uscellForRowAtIndexPathimplementation
– andesta.erfan
Dec 28 '18 at 11:07
How you can load TableView from the other class...... every approach is wrong.
– dahiya_boy
Dec 28 '18 at 11:21
@andesta.erfan I addedcellForRowAtIndexPath, but it just a default and simple implementation to load initial items. I don't have any problem here. I like to see updates after this initial load.
– Afshin
Dec 28 '18 at 11:21
@dahiya_boy each data entry is connected to 1 cell. and I want to update corresponding cell when I update its data.
– Afshin
Dec 28 '18 at 11:22
Something like the 3rd approach. Your view controller should be notified of updates in the view model and it can then reload the appropriate cells
– Paulw11
Dec 28 '18 at 11:26
|
show 5 more comments
I'm very beginner in iOS development, so this problem may look trivial. I searched and could not find any questions about this problem. But I wonder what is correct approach of updating custom cells of a UITableView when you change your data model at run time after initial loading of cells from data model. From change, I mean data entry change, not adding or removing data.
Here is an example. Let's say that I have these DataModel and DataModelCell as follows:
class DataModelView : UITableViewCell {
@IBOutlet weak var mainLabel: UILabel!
}
class DataModel {
var title: String = "" {
didSet {
// which cell this entry is connected to?
}
}
}
...
items: [DataModel] =
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "DataModelView", for: indexPath)
cell.mainLabel?.text = items[indexPath.item].title
// addition line for each approach
// approach 1:
// items[indexPath.item].view = cell
// approach 2:
// items[indexPath.item].viewIndexPath = indexPath
return cell
}
My problem is that when I changed title of one of cells in my data model at run time, I like to update corresponding cell in UI. I like to know what is the best approach to make a relationship between data model'd entry and cell in UITableView.
There are 3 different approaches that comes to my mind. I want to know if they are correct or not or if there is any better method:
1st approach: a weak pointer to cell in my data entry like this:
class DataModel {
weak var view: DataModelView?
var title: String = "" {
didSet {
view?.mainLabel?.text = title
}
}
}
2nd approach: keep IndexPath of cell in my data entry like this:
class DataModel {
var viewIndexPath: IndexPath?
var title: String = "" {
didSet {
// call delegate to controller and ask to update cell for viewIndexPath
}
}
}
3rd approach: don't keep anything which corresponds to cell in data entry:
class DataModel {
var title: String = "" {
didSet {
// call delegate to controller and ask to find and update cell for self
}
}
}
In first 2 approaches, I keep relationship between cell and data model in my data model. In 3rd approach, I need to keep this relationship in controller.
Are all these approaches correct(especially first one)? Which one do you suggest? and What is best approach generally?
I have seen that people keep a pointer to data model in their view in order to update data model from view. I wonder if it is correct in the other way too or not(1st approach).
ios ios-mvc
asked Dec 28 '18 at 10:56
AfshinAfshin
3,0011624
I'm very beginner in iOS development, so this problem may look trivial. I searched and could not find any questions about this problem. But I wonder what is correct approach of updating custom cells of a UITableView when you change your data model at run time after initial loading of cells from data model. From change, I mean data entry change, not adding or removing data.
Here is an example. Let's say that I have these DataModel and DataModelCell as follows:
class DataModelView : UITableViewCell {
@IBOutlet weak var mainLabel: UILabel!
}
class DataModel {
var title: String = "" {
didSet {
// which cell this entry is connected to?
}
}
}
...
items: [DataModel] =
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "DataModelView", for: indexPath)
cell.mainLabel?.text = items[indexPath.item].title
// addition line for each approach
// approach 1:
// items[indexPath.item].view = cell
// approach 2:
// items[indexPath.item].viewIndexPath = indexPath
return cell
}
My problem is that when I changed title of one of cells in my data model at run time, I like to update corresponding cell in UI. I like to know what is the best approach to make a relationship between data model'd entry and cell in UITableView.
There are 3 different approaches that comes to my mind. I want to know if they are correct or not or if there is any better method:
1st approach: a weak pointer to cell in my data entry like this:
class DataModel {
weak var view: DataModelView?
var title: String = "" {
didSet {
view?.mainLabel?.text = title
}
}
}
2nd approach: keep IndexPath of cell in my data entry like this:
class DataModel {
var viewIndexPath: IndexPath?
var title: String = "" {
didSet {
// call delegate to controller and ask to update cell for viewIndexPath
}
}
}
3rd approach: don't keep anything which corresponds to cell in data entry:
class DataModel {
var title: String = "" {
didSet {
// call delegate to controller and ask to find and update cell for self
}
}
}
In first 2 approaches, I keep relationship between cell and data model in my data model. In 3rd approach, I need to keep this relationship in controller.
Are all these approaches correct(especially first one)? Which one do you suggest? and What is best approach generally?
I have seen that people keep a pointer to data model in their view in order to update data model from view. I wonder if it is correct in the other way too or not(1st approach).
ios ios-mvc
ios ios-mvc
asked Dec 28 '18 at 10:56
AfshinAfshin
3,0011624
asked Dec 28 '18 at 10:56
AfshinAfshin
3,0011624
edited Dec 28 '18 at 11:27
Afshin
asked Dec 28 '18 at 10:56
AfshinAfshin
3,0011624
asked Dec 28 '18 at 10:56
AfshinAfshin
3,0011624
asked Dec 28 '18 at 10:56
AfshinAfshin
3,0011624
3,0011624
please show uscellForRowAtIndexPathimplementation
– andesta.erfan
Dec 28 '18 at 11:07
How you can load TableView from the other class...... every approach is wrong.
– dahiya_boy
Dec 28 '18 at 11:21
@andesta.erfan I addedcellForRowAtIndexPath, but it just a default and simple implementation to load initial items. I don't have any problem here. I like to see updates after this initial load.
– Afshin
Dec 28 '18 at 11:21
@dahiya_boy each data entry is connected to 1 cell. and I want to update corresponding cell when I update its data.
– Afshin
Dec 28 '18 at 11:22
Something like the 3rd approach. Your view controller should be notified of updates in the view model and it can then reload the appropriate cells
– Paulw11
Dec 28 '18 at 11:26
|
show 5 more comments
please show uscellForRowAtIndexPathimplementation
– andesta.erfan
Dec 28 '18 at 11:07
How you can load TableView from the other class...... every approach is wrong.
– dahiya_boy
Dec 28 '18 at 11:21
@andesta.erfan I addedcellForRowAtIndexPath, but it just a default and simple implementation to load initial items. I don't have any problem here. I like to see updates after this initial load.
– Afshin
Dec 28 '18 at 11:21
@dahiya_boy each data entry is connected to 1 cell. and I want to update corresponding cell when I update its data.
– Afshin
Dec 28 '18 at 11:22
Something like the 3rd approach. Your view controller should be notified of updates in the view model and it can then reload the appropriate cells
– Paulw11
Dec 28 '18 at 11:26
please show us
cellForRowAtIndexPath implementation– andesta.erfan
Dec 28 '18 at 11:07
please show us
cellForRowAtIndexPath implementation– andesta.erfan
Dec 28 '18 at 11:07
How you can load TableView from the other class...... every approach is wrong.
– dahiya_boy
Dec 28 '18 at 11:21
How you can load TableView from the other class...... every approach is wrong.
– dahiya_boy
Dec 28 '18 at 11:21
@andesta.erfan I added
cellForRowAtIndexPath, but it just a default and simple implementation to load initial items. I don't have any problem here. I like to see updates after this initial load.– Afshin
Dec 28 '18 at 11:21
@andesta.erfan I added
cellForRowAtIndexPath, but it just a default and simple implementation to load initial items. I don't have any problem here. I like to see updates after this initial load.– Afshin
Dec 28 '18 at 11:21
@dahiya_boy each data entry is connected to 1 cell. and I want to update corresponding cell when I update its data.
– Afshin
Dec 28 '18 at 11:22
@dahiya_boy each data entry is connected to 1 cell. and I want to update corresponding cell when I update its data.
– Afshin
Dec 28 '18 at 11:22
Something like the 3rd approach. Your view controller should be notified of updates in the view model and it can then reload the appropriate cells
– Paulw11
Dec 28 '18 at 11:26
Something like the 3rd approach. Your view controller should be notified of updates in the view model and it can then reload the appropriate cells
– Paulw11
Dec 28 '18 at 11:26
|
show 5 more comments
2 Answers
2
active
oldest
votes
4th approach: a weak pointer to data model in the cell and key value observing
class DataModelView : UITableViewCell {
@IBOutlet weak var mainLabel: UILabel!
var observation : NSKeyValueObservation?
weak var model : DataModel? {
didSet {
if model == nil { observation = nil }
else {
observation = model!.observe(.title, options: [.new]) { [weak self] (model, _) in
self?.mainLabel.text = model.title
}
}
}
}
}
KVO requires inheritance from NSObject
class DataModel : NSObject {
@objc dynamic var title: String = ""
}
In cellForRow pass the model
let cell = tableView.dequeueReusableCell(withIdentifier: "DataModelView", for: indexPath) as! DataModelView
cell.model = items[indexPath.row]
and remove the observer in didEndDisplaying
func tableView(_ tableView: UITableView, didEndDisplaying cell: UITableViewCell, forRowAt indexPath: IndexPath) {
(cell as! DataModelView).observation = nil
}
answered Dec 28 '18 at 11:40
vadianvadian
144k13154170
This approach looks great. I think the only drawback is if you have multiple field you like to update or not. if for example you want to update 5-6 fields for cell, you will install a lot of observers which will make code a little messed up. Anyway, thanks for this approach.
– Afshin
Dec 28 '18 at 12:10
add a comment |
It should be like this
class DataModelView: UITableViewCell {
@IBOutlet weak var mainLabel: UILabel!
var yourModel: DataModel? {
didSet {
mainLabel.text = yourModel?.title
}
}
And in your cellForRowAt
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "DataModelView", for: indexPath)
cell.yourData = items[indexPath.item]
return cell
}
After any item changed in your items array just call
tableView.reloadData()
answered Dec 28 '18 at 11:30
Emre ÖnderEmre Önder
811523
The problem is, How OP knows when data is changed in didset?
– dahiya_boy
Dec 28 '18 at 11:31
I think it this a very bad approach.Loading whole table for updating 1 cell is bad...and I cannot find when to do this....
– Afshin
Dec 28 '18 at 11:32
@Afshin As I know, It will look to array and only reload cells that are changed.
– Emre Önder
Dec 28 '18 at 11:33
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
4th approach: a weak pointer to data model in the cell and key value observing
class DataModelView : UITableViewCell {
@IBOutlet weak var mainLabel: UILabel!
var observation : NSKeyValueObservation?
weak var model : DataModel? {
didSet {
if model == nil { observation = nil }
else {
observation = model!.observe(.title, options: [.new]) { [weak self] (model, _) in
self?.mainLabel.text = model.title
}
}
}
}
}
KVO requires inheritance from NSObject
class DataModel : NSObject {
@objc dynamic var title: String = ""
}
In cellForRow pass the model
let cell = tableView.dequeueReusableCell(withIdentifier: "DataModelView", for: indexPath) as! DataModelView
cell.model = items[indexPath.row]
and remove the observer in didEndDisplaying
func tableView(_ tableView: UITableView, didEndDisplaying cell: UITableViewCell, forRowAt indexPath: IndexPath) {
(cell as! DataModelView).observation = nil
}
answered Dec 28 '18 at 11:40
vadianvadian
144k13154170
This approach looks great. I think the only drawback is if you have multiple field you like to update or not. if for example you want to update 5-6 fields for cell, you will install a lot of observers which will make code a little messed up. Anyway, thanks for this approach.
– Afshin
Dec 28 '18 at 12:10
add a comment |
4th approach: a weak pointer to data model in the cell and key value observing
class DataModelView : UITableViewCell {
@IBOutlet weak var mainLabel: UILabel!
var observation : NSKeyValueObservation?
weak var model : DataModel? {
didSet {
if model == nil { observation = nil }
else {
observation = model!.observe(.title, options: [.new]) { [weak self] (model, _) in
self?.mainLabel.text = model.title
}
}
}
}
}
KVO requires inheritance from NSObject
class DataModel : NSObject {
@objc dynamic var title: String = ""
}
In cellForRow pass the model
let cell = tableView.dequeueReusableCell(withIdentifier: "DataModelView", for: indexPath) as! DataModelView
cell.model = items[indexPath.row]
and remove the observer in didEndDisplaying
func tableView(_ tableView: UITableView, didEndDisplaying cell: UITableViewCell, forRowAt indexPath: IndexPath) {
(cell as! DataModelView).observation = nil
}
answered Dec 28 '18 at 11:40
vadianvadian
144k13154170
This approach looks great. I think the only drawback is if you have multiple field you like to update or not. if for example you want to update 5-6 fields for cell, you will install a lot of observers which will make code a little messed up. Anyway, thanks for this approach.
– Afshin
Dec 28 '18 at 12:10
add a comment |
4th approach: a weak pointer to data model in the cell and key value observing
class DataModelView : UITableViewCell {
@IBOutlet weak var mainLabel: UILabel!
var observation : NSKeyValueObservation?
weak var model : DataModel? {
didSet {
if model == nil { observation = nil }
else {
observation = model!.observe(.title, options: [.new]) { [weak self] (model, _) in
self?.mainLabel.text = model.title
}
}
}
}
}
KVO requires inheritance from NSObject
class DataModel : NSObject {
@objc dynamic var title: String = ""
}
In cellForRow pass the model
let cell = tableView.dequeueReusableCell(withIdentifier: "DataModelView", for: indexPath) as! DataModelView
cell.model = items[indexPath.row]
and remove the observer in didEndDisplaying
func tableView(_ tableView: UITableView, didEndDisplaying cell: UITableViewCell, forRowAt indexPath: IndexPath) {
(cell as! DataModelView).observation = nil
}
answered Dec 28 '18 at 11:40
vadianvadian
144k13154170
4th approach: a weak pointer to data model in the cell and key value observing
class DataModelView : UITableViewCell {
@IBOutlet weak var mainLabel: UILabel!
var observation : NSKeyValueObservation?
weak var model : DataModel? {
didSet {
if model == nil { observation = nil }
else {
observation = model!.observe(.title, options: [.new]) { [weak self] (model, _) in
self?.mainLabel.text = model.title
}
}
}
}
}
KVO requires inheritance from NSObject
class DataModel : NSObject {
@objc dynamic var title: String = ""
}
In cellForRow pass the model
let cell = tableView.dequeueReusableCell(withIdentifier: "DataModelView", for: indexPath) as! DataModelView
cell.model = items[indexPath.row]
and remove the observer in didEndDisplaying
func tableView(_ tableView: UITableView, didEndDisplaying cell: UITableViewCell, forRowAt indexPath: IndexPath) {
(cell as! DataModelView).observation = nil
}
answered Dec 28 '18 at 11:40
vadianvadian
144k13154170
edited Dec 28 '18 at 11:45
answered Dec 28 '18 at 11:40
vadianvadian
144k13154170
answered Dec 28 '18 at 11:40
vadianvadian
144k13154170
answered Dec 28 '18 at 11:40
vadianvadian
144k13154170
144k13154170
This approach looks great. I think the only drawback is if you have multiple field you like to update or not. if for example you want to update 5-6 fields for cell, you will install a lot of observers which will make code a little messed up. Anyway, thanks for this approach.
– Afshin
Dec 28 '18 at 12:10
add a comment |
This approach looks great. I think the only drawback is if you have multiple field you like to update or not. if for example you want to update 5-6 fields for cell, you will install a lot of observers which will make code a little messed up. Anyway, thanks for this approach.
– Afshin
Dec 28 '18 at 12:10
This approach looks great. I think the only drawback is if you have multiple field you like to update or not. if for example you want to update 5-6 fields for cell, you will install a lot of observers which will make code a little messed up. Anyway, thanks for this approach.
– Afshin
Dec 28 '18 at 12:10
This approach looks great. I think the only drawback is if you have multiple field you like to update or not. if for example you want to update 5-6 fields for cell, you will install a lot of observers which will make code a little messed up. Anyway, thanks for this approach.
– Afshin
Dec 28 '18 at 12:10
add a comment |
It should be like this
class DataModelView: UITableViewCell {
@IBOutlet weak var mainLabel: UILabel!
var yourModel: DataModel? {
didSet {
mainLabel.text = yourModel?.title
}
}
And in your cellForRowAt
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "DataModelView", for: indexPath)
cell.yourData = items[indexPath.item]
return cell
}
After any item changed in your items array just call
tableView.reloadData()
answered Dec 28 '18 at 11:30
Emre ÖnderEmre Önder
811523
The problem is, How OP knows when data is changed in didset?
– dahiya_boy
Dec 28 '18 at 11:31
I think it this a very bad approach.Loading whole table for updating 1 cell is bad...and I cannot find when to do this....
– Afshin
Dec 28 '18 at 11:32
@Afshin As I know, It will look to array and only reload cells that are changed.
– Emre Önder
Dec 28 '18 at 11:33
add a comment |
It should be like this
class DataModelView: UITableViewCell {
@IBOutlet weak var mainLabel: UILabel!
var yourModel: DataModel? {
didSet {
mainLabel.text = yourModel?.title
}
}
And in your cellForRowAt
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "DataModelView", for: indexPath)
cell.yourData = items[indexPath.item]
return cell
}
After any item changed in your items array just call
tableView.reloadData()
answered Dec 28 '18 at 11:30
Emre ÖnderEmre Önder
811523
The problem is, How OP knows when data is changed in didset?
– dahiya_boy
Dec 28 '18 at 11:31
I think it this a very bad approach.Loading whole table for updating 1 cell is bad...and I cannot find when to do this....
– Afshin
Dec 28 '18 at 11:32
@Afshin As I know, It will look to array and only reload cells that are changed.
– Emre Önder
Dec 28 '18 at 11:33
add a comment |
It should be like this
class DataModelView: UITableViewCell {
@IBOutlet weak var mainLabel: UILabel!
var yourModel: DataModel? {
didSet {
mainLabel.text = yourModel?.title
}
}
And in your cellForRowAt
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "DataModelView", for: indexPath)
cell.yourData = items[indexPath.item]
return cell
}
After any item changed in your items array just call
tableView.reloadData()
answered Dec 28 '18 at 11:30
Emre ÖnderEmre Önder
811523
It should be like this
class DataModelView: UITableViewCell {
@IBOutlet weak var mainLabel: UILabel!
var yourModel: DataModel? {
didSet {
mainLabel.text = yourModel?.title
}
}
And in your cellForRowAt
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "DataModelView", for: indexPath)
cell.yourData = items[indexPath.item]
return cell
}
After any item changed in your items array just call
tableView.reloadData()
answered Dec 28 '18 at 11:30
Emre ÖnderEmre Önder
811523
answered Dec 28 '18 at 11:30
Emre ÖnderEmre Önder
811523
answered Dec 28 '18 at 11:30
Emre ÖnderEmre Önder
811523
answered Dec 28 '18 at 11:30
Emre ÖnderEmre Önder
811523
811523
The problem is, How OP knows when data is changed in didset?
– dahiya_boy
Dec 28 '18 at 11:31
I think it this a very bad approach.Loading whole table for updating 1 cell is bad...and I cannot find when to do this....
– Afshin
Dec 28 '18 at 11:32
@Afshin As I know, It will look to array and only reload cells that are changed.
– Emre Önder
Dec 28 '18 at 11:33
add a comment |
The problem is, How OP knows when data is changed in didset?
– dahiya_boy
Dec 28 '18 at 11:31
I think it this a very bad approach.Loading whole table for updating 1 cell is bad...and I cannot find when to do this....
– Afshin
Dec 28 '18 at 11:32
@Afshin As I know, It will look to array and only reload cells that are changed.
– Emre Önder
Dec 28 '18 at 11:33
The problem is, How OP knows when data is changed in didset?
– dahiya_boy
Dec 28 '18 at 11:31
The problem is, How OP knows when data is changed in didset?
– dahiya_boy
Dec 28 '18 at 11:31
I think it this a very bad approach.Loading whole table for updating 1 cell is bad...and I cannot find when to do this....
– Afshin
Dec 28 '18 at 11:32
I think it this a very bad approach.Loading whole table for updating 1 cell is bad...and I cannot find when to do this....
– Afshin
Dec 28 '18 at 11:32
@Afshin As I know, It will look to array and only reload cells that are changed.
– Emre Önder
Dec 28 '18 at 11:33
@Afshin As I know, It will look to array and only reload cells that are changed.
– Emre Önder
Dec 28 '18 at 11:33
add a comment |
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please show us
cellForRowAtIndexPathimplementation– andesta.erfan
Dec 28 '18 at 11:07
How you can load TableView from the other class...... every approach is wrong.
– dahiya_boy
Dec 28 '18 at 11:21
@andesta.erfan I added
cellForRowAtIndexPath, but it just a default and simple implementation to load initial items. I don't have any problem here. I like to see updates after this initial load.– Afshin
Dec 28 '18 at 11:21
@dahiya_boy each data entry is connected to 1 cell. and I want to update corresponding cell when I update its data.
– Afshin
Dec 28 '18 at 11:22
Something like the 3rd approach. Your view controller should be notified of updates in the view model and it can then reload the appropriate cells
– Paulw11
Dec 28 '18 at 11:26