Can you explain the principle of Content Hugging and how it is used in interface design?

Content Hugging is a concept in interface design that defines how much an interface element tends to occupy the minimum possible space necessary to display its content. In iOS Auto Layout, the Content Hugging Priority property has a numerical value indicating how strongly the element "hugs" its content, preventing it from expanding more than needed.

If an element has a high Content Hugging Priority, it will try not to stretch and will occupy exactly the space needed for its content. When there is a size conflict during layout, the element with the higher Content Hugging Priority will take up less space, yielding to others.

Examples of usage:

• For a button with text, you can increase the Content Hugging Priority horizontally so that the button does not stretch across the entire screen but is exactly as wide as the text.
• For labels that should occupy only as much space as needed for the text, a high Content Hugging Priority is set.

label.setContentHuggingPriority(.defaultHigh, for: .horizontal)
button.setContentHuggingPriority(.required, for: .horizontal)

Thus, Content Hugging helps create adaptive interfaces where elements occupy space proportional to their content without excessive stretching.