Question

Ok i have edited my original post.

Questions was: I have a button that once clicked 3 other button names will change.

from sin to sin-1
from cos to cos-1
from tan to tan-1

As you can tell i am doing a scientific calculator. So far i have declared a IBAtion in .h and now i am implementing this in .m

CODE CORRECTED. for future reference for others.

controller .h

IBOutlet UIButton *btn1;
IBOutlet UIButton *btn2;
IBOutlet UIButton *btn3;

controller .m

-(IBAction)buttonChangeText:(UIButton *)sender
{
    [btn1 setTitle:@"sin-1" forState:UIControlStateNormal];
    [btn2 setTitle:@"cos-1" forState:UIControlStateNormal];
    [btn3 setTitle:@"tan-1" forState:UIControlStateNormal];
}

Answer 1

This will help you to understand, please go with the sender, and use the tag for the button. I will make sense to you. thanks.

- (IBAction)changeTheOtherButton:(id)sender {

    if ([sender tag] == 1) {
        [btn1 setTitle:@"Btn 2" forState:UIControlStateNormal];
    }
    else if ([sender tag] == 2) {
        [btn2 setTitle:@"Btn 1" forState:UIControlStateNormal];
    }

}

enjoy Coding….