Iphone – How to refresh UITableViewCell

cocoa-touchiphoneuitableview

I have a UITableView with a custom UITableViewCell. In cellForRowAtIndexPath, I assign a font to a label in every cell, since the user can change font size at any time. To change font size, the user clicks a button below the tableview, which dislays another view with settings. Once they have chosen a font size and click done, that view goes away and the tableview displays again. I display one cell per viewing area. So the user doesn't see the font change until he scrolls to the next cell. The current cell is the one I'd like to update.

I've tried reloadData from the settings screen but that didn't work. The tableview is a UITableViewController but viewWillAppear never fires once the settings screen goes away. I've tried making the custom cell a property of the tableview so it can be accessed from the settings view, then called setNeedsDisplay and setNeedsLayout. Those didn't work either. Any suggestions?

Best Answer

In your custom UITableViewCell, call [self setNeedsLayout]; and it should repaint your cell at the next loop. I use it for asynchronous image loading since I'm pulling the image from the Web and it works swell.

Related Solutions

Ios – How to disable the UITableView selection

All you have to do is set the selection style on the UITableViewCell instance using either:

Objective-C:

cell.selectionStyle = UITableViewCellSelectionStyleNone;

[cell setSelectionStyle:UITableViewCellSelectionStyleNone];

Swift 2:

cell.selectionStyle = UITableViewCellSelectionStyle.None

Swift 3 and 4.x:

cell.selectionStyle = .none

Further, make sure you either don't implement -tableView:didSelectRowAtIndexPath: in your table view delegate or explicitly exclude the cells you want to have no action if you do implement it.

More info here and here

Iphone – Detect when UITableViewCell goes off the screen

This is an old question, but in case anyone is looking, in iOS6, a new UITableViewDelegate function was introduced that does just this:

- (void)tableView:(UITableView *)tableView didEndDisplayingCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath

It does a great job at telling you whenever a cell is removed, however, it is very thorough and thus if you did a reload cell, even the old cell that's being replaced will trigger this delegate function. In my implementation I simply check to see if the indexPath passed is still within the array tableView.indexPathsForVisibleRows. Something like:

- (void)tableView:(UITableView *)tableView didEndDisplayingCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath
{
    if ([tableView.indexPathsForVisibleRows indexOfObject:indexPath] == NSNotFound)
    {
        // This indeed is an indexPath no longer visible
        // Do something to this non-visible cell...
    }
}

Best Answer

Related Solutions

Ios – How to disable the UITableView selection

Iphone – Detect when UITableViewCell goes off the screen

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