Question

The problem:

1. On top of existing UIView, load a background image
2. From the card deck image (big image), cut 1 card (a part of a big image) and
3. Place that card on top of the background image

The following code works. It does exactly what i need it do to. I ask you though ..

1. Am i doing it right? Is this the way it’s done?
2. Are all steps i used really needed? I have a strong suspicion i made it more complicated then it needs to be

Thank you for your time

// Define overall UIView area and create a view
UIView *background = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 460)];

// Gain access to background image
UIImage *backgroundImage = [UIImage imageNamed:@"green_background.jpg"]; 

// Put background image on top of a 
UIImageView *myImageView = [[UIImageView alloc] initWithImage:backgroundImage];

// So now we have the view of some size with some image bahind it
[background addSubview:myImageView];    


// #####################################################################

CGRect positionOnParentView = CGRectMake(40, 40, 50, 130);

CGImageRef bigImage = [UIImage imageNamed:@"cards.png"].CGImage;    
CGImageRef partOfABigImage = CGImageCreateWithImageInRect(bigImage, CGRectMake(0, 0, 200, 50));

// get an image to be displayed
UIImage *partOfImage = [UIImage imageWithCGImage:partOfABigImage];

// Put it on it's onw view
UIImageView *cardImage = [[UIImageView alloc] initWithImage:partOfImage];

// create a UIview and add image 
UIView *card = [[UIView alloc] initWithFrame:positionOnParentView];
[card addSubview:cardImage];

[background addSubview:card];

[[self view] addSubview:background];

Answer 1

You’re creating this view hierarchy:

UIView (self.view)
  UIView (background)
    UIImageView (backgroundImage - backgroundImage)
    UIView (card)
      UIImageView (cardImage - partOfABigImage)

A UIImageView can have subviews. So do you need all of those intermediate views? Would this simpler hierarchy be sufficient?

UIImageView (self.view - backgroundImage)
  UIImageView (cardImage - partOfABigImage)