CODEWITHSUNDEEP
objective-cuitableview
Wizard Of iOS
Wizard Of iOS

Reputation: 2399

Is it possible to refresh a single UITableViewCell in a UITableView?

I have a custom UITableView using UITableViewCells. Each UITableViewCell has 2 buttons. Clicking these buttons will change an image in a UIImageView within the cell.

Is it possible to refresh each cell separately to display the new image? Any help is appreciated.

Upvotes: 189

Views: 162982

Answers (9)

iphaaw
iphaaw

Reputation: 7204

Here is a UITableView extension with Swift 5:

import UIKit

extension UITableView
{    
    func updateRow(row: Int, section: Int = 0)
    {
        let indexPath = IndexPath(row: row, section: section)
        
        self.beginUpdates()
        self.reloadRows(at: [indexPath], with: .automatic)
        self.endUpdates()
    }
    
}

Call with

self.tableView.updateRow(row: 1)

Upvotes: 4

user1784067
user1784067

Reputation:

I need the upgrade cell but I want close the keyboard. If I use 

let indexPath = NSIndexPath(forRow: path, inSection: 1)
tableView.beginUpdates()
tableView.reloadRowsAtIndexPaths([indexPath], withRowAnimation: UITableViewRowAnimation.Automatic) //try other animations
tableView.endUpdates()

the keyboard disappear

Upvotes: 1

ergunkocak
ergunkocak

Reputation: 3380

Swift 3 : 

tableView.beginUpdates()
tableView.reloadRows(at: [indexPath], with: .automatic)
tableView.endUpdates()

Upvotes: 6

App Dev Guy
App Dev Guy

Reputation: 5536

If you are using custom TableViewCells, the generic

[self.tableView reloadData];

does not effectively answer this question unless you leave the current view and come back. Neither does the first answer.

To successfully reload your first table view cell without switching views, use the following code:

//For iOS 5 and later
- (void)reloadTopCell {
    NSIndexPath *indexPath = [NSIndexPath indexPathForRow:0 inSection:0];
    NSArray *indexPaths = [[NSArray alloc] initWithObjects:indexPath, nil];
    [self.tableView reloadRowsAtIndexPaths:indexPaths withRowAnimation:UITableViewRowAnimationNone];
}

Insert the following refresh method which calls to the above method so you can custom reload only the top cell (or the entire table view if you wish):

- (void)refresh:(UIRefreshControl *)refreshControl {
    //call to the method which will perform the function
    [self reloadTopCell];

    //finish refreshing 
    [refreshControl endRefreshing];
}

Now that you have that sorted, inside of your viewDidLoad add the following:

//refresh table view
UIRefreshControl *refreshControl = [[UIRefreshControl alloc] init];

[refreshControl addTarget:self action:@selector(refresh:) forControlEvents:UIControlEventValueChanged];

[self.tableView addSubview:refreshControl];

You now have a custom refresh table feature that will reload the top cell. To reload the entire table, add the

[self.tableView reloadData]; to your new refresh method.

If you wish to reload the data every time you switch views, implement the method:

//ensure that it reloads the table view data when switching to this view
- (void) viewWillAppear:(BOOL)animated {
    [self.tableView reloadData];
}

Upvotes: 16

Maciek Czarnik
Maciek Czarnik

Reputation: 6181

reloadRowsAtIndexPaths: is fine, but still will force UITableViewDelegate methods to fire.

The simplest approach I can imagine is:

UITableViewCell* cell = [self.tableView cellForRowAtIndexPath:indexPath];
[self configureCell:cell forIndexPath:indexPath];

It's important to invoke your configureCell: implementation on main thread, as it wont work on non-UI thread (the same story with reloadData/reloadRowsAtIndexPaths:). Sometimes it might be helpful to add:

dispatch_async(dispatch_get_main_queue(), ^
{
    [self configureCell:cell forIndexPath:indexPath];
});

It's also worth to avoid work that would be done outside of the currently visible view:

BOOL cellIsVisible = [[self.tableView indexPathsForVisibleRows] indexOfObject:indexPath] != NSNotFound;
if (cellIsVisible)
{
    ....
}

Upvotes: 17

Esqarrouth
Esqarrouth

Reputation: 39181

Swift:

func updateCell(path:Int){
    let indexPath = NSIndexPath(forRow: path, inSection: 1)

    tableView.beginUpdates()
    tableView.reloadRowsAtIndexPaths([indexPath], withRowAnimation: UITableViewRowAnimation.Automatic) //try other animations
    tableView.endUpdates()
}

Upvotes: 22

Romain
Romain

Reputation: 4080

Once you have the indexPath of your cell, you can do something like:

[self.tableView beginUpdates];
[self.tableView reloadRowsAtIndexPaths:[NSArray arrayWithObjects:indexPathOfYourCell, nil] withRowAnimation:UITableViewRowAnimationNone];
[self.tableView endUpdates];

In Xcode 4.6 and higher:

[self.tableView beginUpdates];
[self.tableView reloadRowsAtIndexPaths:@[indexPathOfYourCell] withRowAnimation:UITableViewRowAnimationNone];
[self.tableView endUpdates];

You can set whatever your like as animation effect, of course.

Upvotes: 331

Gregory Hill
Gregory Hill

Reputation: 110

Just to update these answers slightly with the new literal syntax in iOS 6--you can use Paths = @[indexPath] for a single object, or Paths = @[indexPath1, indexPath2,...] for multiple objects.

Personally, I've found the literal syntax for arrays and dictionaries to be immensely useful and big time savers. It's just easier to read, for one thing. And it removes the need for a nil at the end of any multi-object list, which has always been a personal bugaboo. We all have our windmills to tilt with, yes? ;-)

Just thought I'd throw this into the mix. Hope it helps.

Upvotes: 3

ma11hew28
ma11hew28

Reputation: 126319

I tried just calling -[UITableView cellForRowAtIndexPath:], but that didn't work. But, the following works for me for example. I alloc and release the NSArray for tight memory management.

- (void)reloadRow0Section0 {
    NSIndexPath *indexPath = [NSIndexPath indexPathForRow:0 inSection:0];
    NSArray *indexPaths = [[NSArray alloc] initWithObjects:indexPath, nil];
    [self.tableView reloadRowsAtIndexPaths:indexPaths withRowAnimation:UITableViewRowAnimationNone];
    [indexPaths release];
}

Upvotes: 34

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