How to give Image from another thread?
I have a code for getting user pic:
if let photoURL = message[Constants.MessageFields.photoURL], let URL = URL(string: photoURL),
let data = try? Data(contentsOf: URL) {
cell.userPic.image = UIImage(data: data)
}
When I'm using it, tableView lagging at scrolling.
Please help me to put this code in another thread.
swift multithreading
asked Nov 21 at 8:08
Артем Ильинский
969
add a comment |
I have a code for getting user pic:
if let photoURL = message[Constants.MessageFields.photoURL], let URL = URL(string: photoURL),
let data = try? Data(contentsOf: URL) {
cell.userPic.image = UIImage(data: data)
}
When I'm using it, tableView lagging at scrolling.
Please help me to put this code in another thread.
swift multithreading
asked Nov 21 at 8:08
Артем Ильинский
969
add a comment |
I have a code for getting user pic:
if let photoURL = message[Constants.MessageFields.photoURL], let URL = URL(string: photoURL),
let data = try? Data(contentsOf: URL) {
cell.userPic.image = UIImage(data: data)
}
When I'm using it, tableView lagging at scrolling.
Please help me to put this code in another thread.
swift multithreading
asked Nov 21 at 8:08
Артем Ильинский
969
I have a code for getting user pic:
if let photoURL = message[Constants.MessageFields.photoURL], let URL = URL(string: photoURL),
let data = try? Data(contentsOf: URL) {
cell.userPic.image = UIImage(data: data)
}
When I'm using it, tableView lagging at scrolling.
Please help me to put this code in another thread.
swift multithreading
swift multithreading
asked Nov 21 at 8:08
Артем Ильинский
969
asked Nov 21 at 8:08
Артем Ильинский
969
asked Nov 21 at 8:08
Артем Ильинский
969
asked Nov 21 at 8:08
Артем Ильинский
969
asked Nov 21 at 8:08
Артем Ильинский
969
969
add a comment |
add a comment |
1 Answer
1
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oldest
votes
Here is a good sample provided by Apple, that you can adapt for your needs:
Prefetching collection view data
Basic idea is to create AsyncFetcher for your images and put image creation code to separate operation.
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
guard let cell = collectionView.dequeueReusableCell(withReuseIdentifier: Cell.reuseIdentifier, for: indexPath) as? Cell else {
fatalError("Expected `(Cell.self)` type for reuseIdentifier (Cell.reuseIdentifier). Check the configuration in Main.storyboard.")
}
let model = models[indexPath.row]
let id = model.id
cell.representedId = id
// Check if the `asyncFetcher` has already fetched data for the specified identifier.
if let fetchedData = asyncFetcher.fetchedData(for: id) {
// The data has already been fetched and cached; use it to configure the cell.
cell.configure(with: fetchedData)
} else {
// There is no data available; clear the cell until we've fetched data.
cell.configure(with: nil)
// Ask the `asyncFetcher` to fetch data for the specified identifier.
asyncFetcher.fetchAsync(id) { fetchedData in
DispatchQueue.main.async {
/*
The `asyncFetcher` has fetched data for the identifier. Before
updating the cell, check if it has been recycled by the
collection view to represent other data.
*/
guard cell.representedId == id else { return }
// Configure the cell with the fetched image.
cell.configure(with: fetchedData)
}
}
}
return cell
}
But in your case you should use Table View prefetching
I can confirm that this approach works and (when done right) results smooth scrolling and good UX
answered Nov 21 at 8:19
fewlinesofcode
2,024518
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
Here is a good sample provided by Apple, that you can adapt for your needs:
Prefetching collection view data
Basic idea is to create AsyncFetcher for your images and put image creation code to separate operation.
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
guard let cell = collectionView.dequeueReusableCell(withReuseIdentifier: Cell.reuseIdentifier, for: indexPath) as? Cell else {
fatalError("Expected `(Cell.self)` type for reuseIdentifier (Cell.reuseIdentifier). Check the configuration in Main.storyboard.")
}
let model = models[indexPath.row]
let id = model.id
cell.representedId = id
// Check if the `asyncFetcher` has already fetched data for the specified identifier.
if let fetchedData = asyncFetcher.fetchedData(for: id) {
// The data has already been fetched and cached; use it to configure the cell.
cell.configure(with: fetchedData)
} else {
// There is no data available; clear the cell until we've fetched data.
cell.configure(with: nil)
// Ask the `asyncFetcher` to fetch data for the specified identifier.
asyncFetcher.fetchAsync(id) { fetchedData in
DispatchQueue.main.async {
/*
The `asyncFetcher` has fetched data for the identifier. Before
updating the cell, check if it has been recycled by the
collection view to represent other data.
*/
guard cell.representedId == id else { return }
// Configure the cell with the fetched image.
cell.configure(with: fetchedData)
}
}
}
return cell
}
But in your case you should use Table View prefetching
I can confirm that this approach works and (when done right) results smooth scrolling and good UX
answered Nov 21 at 8:19
fewlinesofcode
2,024518
add a comment |
Here is a good sample provided by Apple, that you can adapt for your needs:
Prefetching collection view data
Basic idea is to create AsyncFetcher for your images and put image creation code to separate operation.
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
guard let cell = collectionView.dequeueReusableCell(withReuseIdentifier: Cell.reuseIdentifier, for: indexPath) as? Cell else {
fatalError("Expected `(Cell.self)` type for reuseIdentifier (Cell.reuseIdentifier). Check the configuration in Main.storyboard.")
}
let model = models[indexPath.row]
let id = model.id
cell.representedId = id
// Check if the `asyncFetcher` has already fetched data for the specified identifier.
if let fetchedData = asyncFetcher.fetchedData(for: id) {
// The data has already been fetched and cached; use it to configure the cell.
cell.configure(with: fetchedData)
} else {
// There is no data available; clear the cell until we've fetched data.
cell.configure(with: nil)
// Ask the `asyncFetcher` to fetch data for the specified identifier.
asyncFetcher.fetchAsync(id) { fetchedData in
DispatchQueue.main.async {
/*
The `asyncFetcher` has fetched data for the identifier. Before
updating the cell, check if it has been recycled by the
collection view to represent other data.
*/
guard cell.representedId == id else { return }
// Configure the cell with the fetched image.
cell.configure(with: fetchedData)
}
}
}
return cell
}
But in your case you should use Table View prefetching
I can confirm that this approach works and (when done right) results smooth scrolling and good UX
answered Nov 21 at 8:19
fewlinesofcode
2,024518
add a comment |
Here is a good sample provided by Apple, that you can adapt for your needs:
Prefetching collection view data
Basic idea is to create AsyncFetcher for your images and put image creation code to separate operation.
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
guard let cell = collectionView.dequeueReusableCell(withReuseIdentifier: Cell.reuseIdentifier, for: indexPath) as? Cell else {
fatalError("Expected `(Cell.self)` type for reuseIdentifier (Cell.reuseIdentifier). Check the configuration in Main.storyboard.")
}
let model = models[indexPath.row]
let id = model.id
cell.representedId = id
// Check if the `asyncFetcher` has already fetched data for the specified identifier.
if let fetchedData = asyncFetcher.fetchedData(for: id) {
// The data has already been fetched and cached; use it to configure the cell.
cell.configure(with: fetchedData)
} else {
// There is no data available; clear the cell until we've fetched data.
cell.configure(with: nil)
// Ask the `asyncFetcher` to fetch data for the specified identifier.
asyncFetcher.fetchAsync(id) { fetchedData in
DispatchQueue.main.async {
/*
The `asyncFetcher` has fetched data for the identifier. Before
updating the cell, check if it has been recycled by the
collection view to represent other data.
*/
guard cell.representedId == id else { return }
// Configure the cell with the fetched image.
cell.configure(with: fetchedData)
}
}
}
return cell
}
But in your case you should use Table View prefetching
I can confirm that this approach works and (when done right) results smooth scrolling and good UX
answered Nov 21 at 8:19
fewlinesofcode
2,024518
Here is a good sample provided by Apple, that you can adapt for your needs:
Prefetching collection view data
Basic idea is to create AsyncFetcher for your images and put image creation code to separate operation.
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
guard let cell = collectionView.dequeueReusableCell(withReuseIdentifier: Cell.reuseIdentifier, for: indexPath) as? Cell else {
fatalError("Expected `(Cell.self)` type for reuseIdentifier (Cell.reuseIdentifier). Check the configuration in Main.storyboard.")
}
let model = models[indexPath.row]
let id = model.id
cell.representedId = id
// Check if the `asyncFetcher` has already fetched data for the specified identifier.
if let fetchedData = asyncFetcher.fetchedData(for: id) {
// The data has already been fetched and cached; use it to configure the cell.
cell.configure(with: fetchedData)
} else {
// There is no data available; clear the cell until we've fetched data.
cell.configure(with: nil)
// Ask the `asyncFetcher` to fetch data for the specified identifier.
asyncFetcher.fetchAsync(id) { fetchedData in
DispatchQueue.main.async {
/*
The `asyncFetcher` has fetched data for the identifier. Before
updating the cell, check if it has been recycled by the
collection view to represent other data.
*/
guard cell.representedId == id else { return }
// Configure the cell with the fetched image.
cell.configure(with: fetchedData)
}
}
}
return cell
}
But in your case you should use Table View prefetching
I can confirm that this approach works and (when done right) results smooth scrolling and good UX
answered Nov 21 at 8:19
fewlinesofcode
2,024518
answered Nov 21 at 8:19
fewlinesofcode
2,024518
answered Nov 21 at 8:19
fewlinesofcode
2,024518
answered Nov 21 at 8:19
fewlinesofcode
2,024518
2,024518
add a comment |
add a comment |
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