UIButton with target:self not being sent to self? - ios

Question

I'm creating a new UIViewController (call it MyViewController), and adding the view (MyView) as a subview of a TableViewCell. Within MyView , there's a button. That button is created programmatically during MyViewController's init, as such:
-(id)initWithFrame:(CGRect)frame {
self = [super init];
if(self) {
[self.view setFrame:frame];
_yesButton = [[UIButton alloc] initWithFrame:CGRectMake(frame.size.width-150, 40, 140, 30)];
[_yesButton setTitle:#"Yeah!" forState:UIControlStateNormal];
[_yesButton addTarget:self action:#selector(didClick) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:_yesButton];
}
return self;
}
Now, seems straightforward. It displays properly, everything looks great in the simulator.
But when I click on the "_yesButton" within MyView, I get a crash with this error:
-[_UITableViewCellSeparatorView didClick]: unrecognized selector sent to instance 0x7b7f7ec0
What? When did "_UITableViewCellSeparatorView" come into the equation? I specifically told the _yesButton to set the Target to "self", so the selector should be sent to MyViewController, right? I could even imagine it getting tripped up and sending it to the UITableViewCell, since MyView is embedded within a TableViewCell, but why a SeperatorView?
Can anyone tell me how to get my _yesButton to send the call back to the MyViewController that it's being created within? And for bonus points, can you explain how "_UITableViewCellSeparatorView" became a thing in this conversation at all?
Edit: Here's how I'm building the cell in the TableView, and adding MyView to it. Note that I'm deliberately not using dequeuing for this row, although that might change if it's the source of the problem.
UITableViewCell *cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:#"MyViewCell"];
MyViewController *myViewController = [[MyViewController alloc] initWithFrame:cell.contentView.frame];
[cell.contentView addSubview:myViewController.view];
return cell;
And the didClick method is currently empty, (it never even gets there, so I haven't gotten that far in writing it), but it's currently defined within MyViewController simply as:
-(void)didClick {
}

Answer 1

Solution #1
Actually this is because you MyViewController is not retain by ARC. The dealloc method id being called. Add ans instance of your controller in your UITableViewController will fix the issue and make ARC retains your controller.
Solution #2
Try something like this.
Create a custom UITableViewCell :
MyCustomCell.h :
#import <UIKit/UIKit.h>
#interface MyCustomCell : UITableViewCell
#property (strong, nonatomic) UIButton *yesButton;
-(id)initWithFrame:(CGRect)frame;
#end
MyCustomCell.m :
#import "MyCustomCell.h"
#implementation MyCustomCell
- (void)setSelected:(BOOL)selected animated:(BOOL)animated {
[super setSelected:selected animated:animated];
// Configure the view for the selected state
}
-(id)initWithFrame:(CGRect)frame {
self = [super init];
if(self) {
[self.view setFrame:frame];
_yesButton = [[UIButton alloc] initWithFrame:CGRectMake(frame)];
[_yesButton setTitle:#"Yeah!" forState:UIControlStateNormal];
[self.contentView addSubview:_yesButton];
}
return self;
}
#end
In your UITableViewControllerin the viewDidLoad function :
[self.tableView registerClass:[MyCustomCell class] forCellReuseIdentifier:CellIdentifier];
Then in your tableView:cellForRowAtIndexPath:
MyCustomCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifierr forIndexPath:indexPath];
if (cell == nil) {
cell = [[MyCustomCell alloc] initWithFrame:frame];
[cell.yesButton addTarget:self action:#selector(didClick) forControlEvents:UIControlEventTouchUpInside];
}
And now implement the following in your UITableViewController:
-(void)didClick {
// The following identify the in which cell the action has been triggered
NSSet *touches = [event allTouches];
UITouch *touch = [touches anyObject];
CGPoint currentTouchPosition = [touch locationInView:self.tableView];
NSIndexPath *indexPath = [self.tableView indexPathForRowAtPoint: currentTouchPosition];
if (indexPath != nil)
{
// Do whatever you want for the given cell
}
}

Answer 2

I think that you're adopting a wrong approach.
The view cells are not living in memory like views. We may say that once the drawing done, it does not exists anymore.
For all cells operations, you should set you TableViewController as target, and handle the click method in this controller.
Only this controller has a global knowledge of the data in the cells and the cells formats.
You can set the tag of the button to the row index to know what row has been clicked.
your didClick selector is also not correct. It should have this form
-(void)didClick:(id)sender
{
NSInteger clickedRow = ((UIButton*)sender).tag
}
And so be connected like this:
[_yesButton addTarget:<YourTableController> action:#selector(didClick:) forControlEvents:UIControlEventTouchUpInside];

Answer 3

The problem is that the instance you thing to be kind of MyViewController, it is no. It is instead UITableViewCellSeparatorView.
The biggest error, is that you are trying to init a view controller by a method which is not supported from the class UIViewController, but is instead part of UIView:
- (id)initWithFrame:(CGRect)frame
I suggest you to review it before going ahead.