Question

- (UIImage*)returnRandomBackground{
    int selectedImage = (arc4random() % 4) + 1;
    UIImage *imageToReturn;
    if (selectedImage == 1) {
        imageToReturn = Image1;
    }

    else if (selectedImage == 2) {
        imageToReturn = Image2;
    }

    else if (selectedImage == 3) {
        imageToReturn = Image3;
    }

    else if (selectedImage == 4) {
        imageToReturn = Image4;
    }

    return imageToReturn;
}

UnDefined or garbage value returned to caller.

To me this code looks legal, whats wrong with it?

Answer 1

The compiler will think that it’s possible that there’s a selectedImage = 5, which means there’s a possibility of imageReturn remaining unassigned. You’ll have to change the last else if to just an else to make sure imageReturn is always assigned.

Look at what the code would do if selectedImage = 5. It’ll break.