change image on click of button in objective c

Question

i draged 3 button in my .xib file (btn1,btn2,btn3 respectively) and initially i given default image to them, first.png

now when user clicks on btn1, image of btn1 should

Answer 1

    #import 


    @interface CustomRadioButton : UIButton {

    }

    @end


#import "CustomRadioButton.h"


@implementation CustomRadioButton

- (id)initWithFrame:(CGRect)frame {
    if (self = [super initWithFrame:frame]) {
        // Set the refresh icon as the button's image
        [self setImage:[UIImage imageNamed:@"off.png"] forState:UIControlStateNormal];
        [self setImage:[UIImage imageNamed:@"on.png"] forState:UIControlStateSelected];
        // When the button is pressed, draw to button with less opacity.
        self.adjustsImageWhenHighlighted = YES;

    }
    return self;
}

@end

inside the Implement file of the viewController

- (void)viewDidLoad {
    [super viewDidLoad];
    for (int i=1;i<=2;i++){

        CustomRadioButton *Radiobutton = [CustomRadioButton buttonWithType:UIButtonTypeCustom];

        Radiobutton = [[CustomRadioButton alloc] initWithFrame:CGRectMake(200,50*i, 30, 30)];

        [Radiobutton addTarget:self action:@selector(checkboxButton:) forControlEvents:UIControlEventTouchUpInside];

        Radiobutton.tag=i;

        [self.view addSubview:Radiobutton];

        }

}


    - (IBAction)checkboxButton:(UIButton *)button{

        for (UIButton *Radiobutton in [self.view subviews]) {
            if ([Radiobutton isKindOfClass:[UIButton class]] && ![Radiobutton isEqual:button]) {
                [Radiobutton setSelected:NO];
            }
        }
        if (!button.selected) {
            button.selected = !button.selected;

    }
}