Getting UITableViewCell with superview in iOS 7

9
votes

I'm getting the UITableViewCell a UIButton belongs to like this:

-(void)buttonHandler:(UIButton *)button {

    OrderCell *cell = [[button superview] superview];
    NSLog(@"cell.item = %@", cell.item.text);

And it works fine in anything before iOS 7. But gives me:

[UITableViewCellScrollView item]: unrecognized selector sent to instance 0x17ae2cf0

if I run the app in iOS 7. BUT if I do:

-(void)buttonHandler:(UIButton *)button {

    OrderCell *cell = [[[button superview] superview] superview];
    NSLog(@"cell.item = %@", cell.item.text);

Then it works in iOS 7 but not earlier?!?!?!

I'm circumventing the issue by doing this:

OrderCell *cell;
if([[[UIDevice currentDevice] systemVersion] isEqualToString:@"7.0"])
    cell = [[[button superview] superview] superview];
else
    cell = [[button superview] superview];

NSLog(@"cell.item = %@", cell.item.text);

but WTF is going on!? Does anyone know why this happens?

Thanks!

5
iosobjective-csuperview
Your code was depending on the private subview structure of UITableViewCell. Obviously that structure has changed in iOS 7. There are much safer ways to do what you want. And your new code will break under iOS 7.1 and iOS 8. - rmaddy
@rmaddy What is the safer way? - Mundi
You could iterate through the superviews, checking if they are of class type UITableViewCell and then return that view ? See answer: - CW0007007
@thehindutimes - Yes, what CW0007007 said. - rmaddy
True, thanks for the feedback everyone! - thehindutimes

5 Answers

27
votes

A better solution is to add a category for UIView(SuperView), and calling it by:

UITableViewCell *cell = [button findSuperViewWithClass:[UITableViewCell class]]

This way, your code works for all future and past iOS versions

@interface UIView (SuperView)

- (UIView *)findSuperViewWithClass:(Class)superViewClass;

@end


@implementation UIView (SuperView)

- (UIView *)findSuperViewWithClass:(Class)superViewClass {

    UIView *superView = self.superview;
    UIView *foundSuperView = nil;

    while (nil != superView && nil == foundSuperView) {
        if ([superView isKindOfClass:superViewClass]) {
            foundSuperView = superView;
        } else {
            superView = superView.superview;
        }
    }
    return foundSuperView;
}
@end
13
votes

The best way to do this is:

CGPoint buttonPosition = [sender convertPoint:CGPointZero toView:self.tableView];
NSIndexPath *indexPath = [self.tableView indexPathForRowAtPoint:buttonPosition];
UITableViewCell *cell = (UITableViewCell*)[self.tableView cellForRowAtIndexPath:indexPath];
3
votes

To complete the answer of @thomas-keuleers this is the swift method: 

extension UIView {

    func findSuperViewWithClass<T>(superViewClass : T.Type) -> UIView? {

        var xsuperView : UIView!  = self.superview!
        var foundSuperView : UIView!

        while (xsuperView != nil && foundSuperView == nil) {

            if xsuperView.self is T {
                foundSuperView = xsuperView
            } else {
                xsuperView = xsuperView.superview
            }
        }
        return foundSuperView
    }

}

and you simply call like that:

child.findSuperViewWithClass(TableViewCell)
0
votes

A shorter Version in swift 5

extension UIView {
   var xsuperView = self.superview

   while xsuperView != nil {
        if let superView = xsuperView.self as? T {
            return superView
        } else {
            xsuperView = xsuperView?.superview
        }
    }
}
-2
votes
if ([[button superView] isKindOfClass:[UITableViewCell class]]) {

}

else //check next :