Question

I need to make a 9×9 button grid (like a sudoku board) for the user to interact (simply touch the screen) and capture the “coordinates” of the pressed button…

Any ideas on how to solve this?

thanks in advance.

Answer 1

Not sure why you want that, but I prepared this for you:

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view from its nib.
    for (int y=0; y < 3; y++) {
        for (int x = 0; x < 3; x++) {
            UIButton * button = [UIButton buttonWithType:UIButtonTypeRoundedRect];
            button.frame = CGRectMake(40 + 80 * x, 40 + 80 * y, 80, 80);
            unsigned buttonNumber = y * 3 + x + 1;
            button.tag = buttonNumber;
            [button setTitle:[NSString stringWithFormat:@"%u", buttonNumber] forState:UIControlStateNormal];
            [button addTarget:self action:@selector(buttonPressed:) forControlEvents:UIControlEventTouchUpInside];
            [self.view addSubview: button];
        }
    }
}

-(void)buttonPressed:(UIButton *)button
{
    NSLog(@"button %u -- frame: %@", button.tag, NSStringFromCGRect(button.frame));
}

Basically, all buttons use the same callback, and there you can check the button frame as needed. If you do not need the location, but just know which button was pressed, you could simply use a tag for each button, and check the tag property on the callback.