Remove Subview of UIButton - iphone

Question

im running the same piece of code over and over when the user presses a button. If the user presses the button an image appears over the button, if they press it again the image is removed from the buttons subview.
here is my code:
UIImageView *overlay = [[UIImageView alloc]initWithImage:[UIImage imageNamed:#"OverlayImage.png"]];
NSString *senderstag = [NSString stringWithFormat:#"%i", buttonFromSender.tag];
if([[dictonaryOfImagesToDelete allKeys] containsObject:senderstag]){
[[buttonFromSender subviews]makeObjectsPerformSelector:#selector(removeFromSuperview)];
}
else{
[buttonFromSender addSubview:overlay];
}
NSString *imageName = [[NSString alloc]init];
imageName = [arrayWithImageNames objectAtIndex:buttonFromSender.tag];
[imagesToDelete addObject:imageName];
[dictonaryOfImagesToDelete setObject:imagesToDelete forKey:[NSString stringWithFormat:#"%i", buttonFromSender.tag]];
Im using a dictionary to keep track of which buttons have been pressed. instead of the imageview over the button being removed, it removes the whole button. How can i get it just to remove the imageview and not the button?
Thanks :D

Answer 1

I have ended up making the UIImageview of the overlay, a UIButton. This allowed to set actions for it. Here is the code that is used:
UIImage *image = [UIImage imageNamed:#"OverlayImage.png"];
UIButton *overlay = [[UIButton alloc]init];
overlay.frame = CGRectMake(0, 0, 100, 150);
[overlay setImage:image forState:UIControlStateNormal];
[overlay addTarget:self action:#selector(removeSelectedImage:) forControlEvents:UIControlEventTouchUpInside];
overlay.tag = buttonFromSender.tag;
[buttonFromSender addSubview:overlay];
NSString *imageName = [[NSString alloc]init];
imageName = [arrayWithImageNames objectAtIndex:buttonFromSender.tag];
[imagesToDelete addObject:imageName];
[dictonaryOfImagesToDelete setObject:imageName forKey:[NSString stringWithFormat:#"%i", buttonFromSender.tag]];
this set up the new UIButton
then to get rid of the UIButton i did this:
-(IBAction)removeSelectedImage:(id)sender{
UIButton *button = (UIButton *)sender;
[button removeFromSuperview];
NSString *tag = [NSString stringWithFormat:#"%i", button.tag];
NSString *deleteWhat = [[NSString alloc]init];
deleteWhat = [dictonaryOfImagesToDelete objectForKey:tag];
[imagesToDelete removeObject:deleteWhat];
[dictonaryOfImagesToDelete removeObjectForKey:tag];
}

Answer 2

If you want to display different image for a button state u can directly initialize the button with to load a picture in that state.
say for example Enabled/Disabled, or Selected/Deselected(normal)
UIButton* myButton = [UIButton buttonWithType:UIButtonTypeCustom];
[myButton setImage:[UIImage imageNamed:#"My Image"] forState:UIControlStateNormal];
[myButton setImage:[UIImage imageNamed:#"My Other Image"] forState:UIControlStateSelected];
[myButton setBackgroundImage:[UIImage imageNamed:#"BG Img"] forState:UIControlStateNormal];
References:
Background Image:
http://developer.apple.com/library/IOS/documentation/UIKit/Reference/UIButton_Class/UIButton/UIButton.html#//apple_ref/occ/instm/UIButton/backgroundImageForState:
Button Image:
http://developer.apple.com/library/IOS/documentation/UIKit/Reference/UIButton_Class/UIButton/UIButton.html#//apple_ref/occ/instm/UIButton/setImage:forState: