Displaying a UIViewController/UIView over another view

Answer 1

Probably I just don't get it, but I don't exactly understand what's the problem here. In the bottom screenshot, should the UI elements be transparent, without the white area above? You need to set the frame of the UIView in your UIViewController appropriately and I guess you might have to set the background color transparent:

self.view.backgroundColor = [UIColor clearColor];

I'm not sure, since I never use the IB, but it may be possible to set the Alpha value of the background color of the base view to 0. Not the alpha of the view itself, but of the background color.

Answer 2

The solution seems to be not to use a UIViewController instead a simple custom UIView does the job nicely.

I used Haentz's color setup in the awakeFromNib method:

- (void)awakeFromNib {
    picker.delegate = self;
    self.backgroundColor = [UIColor clearColor];    
}

Note that you have to implement this and not using the initWithFrame method that the x-code template gives you as nib controlled views don't use initWithFrame (from the apple documentation).