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iOS

Scott Evans
Scott Evans
4,236 Points
Posted by Scott Evans
Scott Evans
4,236 Points

iOS UIButton events - Objective C @selector

Im having an issue which i can't seem to get my head around.

The situation is:

I have a UIButton within a SubClass of UITableViewCell ( for custom cell stuff). What i need to do is find a way to execute a method from the main view controller if one of these UIButtons is pressed within a table cell. This method needs to be passed particular data to allow me to reference it to actual data i will use for a manipulation.

Here is what I've tried so far

MainViewController.m

[cell.addButton addTarget:self action:@selector(addToNote:withPriceIndex:) forControlEvents:UIControlEventTouchUpInside];

In this example the selector gets called correctly but I'm not quite sure how to pass the variables that i need to be passed, to allow me to capture the data that button relates to.

If anyone who has experience working with selectors, or knows another solution it would be greatly appreciated!

Thank you in advance, Scott.

Scott Evans
Scott Evans
4,236 Points
Scott Evans
Scott Evans
4,236 Points

Stone Preston , i believe you might be able to help me here if you get a chance.

Scott Evans
Scott Evans
4,236 Points
Scott Evans
Scott Evans
4,236 Points

Okay, ive realised you cannot send custom parameters to an action:selector as it only takes the event sender & event.

Scott Evans
Scott Evans
4,236 Points
Scott Evans
Scott Evans
4,236 Points

I guess my next question would be, how do i access the particular instance of the class that corresponds to a particular CustomTableViewCell button

1 Answer

Scott Evans
Scott Evans
4,236 Points
Scott Evans
Scott Evans
4,236 Points

I think i found my own solution. I managed to find the indexPath of the cell where a button was pressed and then managed to use that to access my datasource and table view to get the required data & classes.

Below is the code just incase it helps anyone else.

-(void)addToNote:(id)sender{
    NSLog(@"Add to note");

    CGPoint buttonOriginInTableView = [sender convertPoint:CGPointZero toView:self.tableView];
    NSIndexPath *indexPath = [self.tableView indexPathForRowAtPoint:buttonOriginInTableView];

    CoreDataClass *crData = [_fetchedResultsController objectAtIndexPath:indexPath];
    CustomTableCell *cell = (CustomTableCell *)[self.tableView cellForRowAtIndexPath:indexPath];
}