Question

I have a custom UITableViewCell, which have a button on it, IB linked to a function called:

- (IBAction)clickUse:(id)sender;

In this function, I planned to pass an object from UITableView‘s data source (an object in a NSMutableArray) to next UIViewController, when the user clicks the button on the UITableViewCell.

I set a property in the custom UITableViewCell, like this:

@property (nonatomic, retain) SomeObject *some_object;

In UITableView‘s cellForRowAtIndexPath function, I pass the object to the cell:

MyCustomCell *cell = (MyCustomCell *)[tableView dequeueReusableCellWithIdentifier:identifier];
cell.some_object = [self.cellData objectAtIndex:indexPath.row];

At this moment I track the object, it’s still here. But in the MyCustomCell cell, the object is gone and assigned to nil. Therefore, the object cannot be passed to next UIViewController.

What did I miss?

Answer 1

Perhaps it’s better to use a different approach. You can give each cell button a tag. The tag value could be the row index path.

Your -tableView:cellForRowAtIndexPath: method could include the following:

MyCustomCell *cell = (MyCustomCell *)[tableView dequeueReusableCellWithIdentifier:identifier];
cell.button.tag = indexPath.row

And your -clickUse: method could look like this:

- (IBAction)clickUse:(id)sender
{
    UIButton *button = (UIButton *)sender;
    SomeObject *object = [self.cellData objectAtIndex:button.tag];

    // do stuff with your object on click
}