How to create custom 'init' method in Objective C

- (id)init

{

    if (self = [super init]) {

       

         //you can implement custom class here

    }

   

    return self;

}

Radio buttons for iPhone application

Add buttons on view of controller

        for (int i = 0; i < 3; i++) {

            UIButton *but = [UIButton buttonWithType:UIButtonTypeCustom];

            [but setImage:[UIImage imageNamed:@"checkbox.png"] forState:UIControlStateNormal];

            [but setImage:[UIImage imageNamed:@"checkedbox.png"] forState:UIControlStateSelected];

            [but setFrame:CGRectMake(0, 0, 25, 25)];

            [but setCenter:CGPointMake(410, 385+i*40)];

            if (i == 0) {

                [but setSelected:YES];

            }

            [but setTag:i];

            [but addTarget:self action:@selector(checkboxButton:) 

                                                          forControlEvents:UIControlEventTouchUpInside];

            [self addSubview:but];

        }

Action for buttons:

- (void)checkboxButton:(UIButton *)button

{

    for (UIButton *but in [self subviews]) { // This is the view that button are in

        if ([but isKindOfClass:[UIButton class]] && ![but isEqual:button]) {

            [but setSelected:NO];

        }

    }

    if (!button.selected) {

        button.selected = !button.selected;

    }

}