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# UILetterformAwareAdjusting

The typographic bounds-sizing behavior to handle text with fonts that contain oversize characters.

```
@MainActor protocol UILetterformAwareAdjusting : NSObjectProtocol
```

## Overview

In [`UILabel`](/documentation/UIKit/UILabel), [`UITextField`](/documentation/UIKit/UITextField), or a nonscrollable [`UITextView`](/documentation/UIKit/UITextView), [`sizeThatFits(_:)`](/documentation/UIKit/UIView/sizeThatFits(_:)) and [`intrinsicContentSize`](/documentation/UIKit/UIView/intrinsicContentSize) increase the height calculated for tall scripts when you present text that contains oversize characters in a font that you create with  [`preferredFont(forTextStyle:)`](/documentation/UIKit/UIFont/preferredFont(forTextStyle:)). Even with the increase, some extreme ascenders and descenders may extend beyond the view’s bounds and appear to be clipped. For nontext-style fonts, [`sizeThatFits(_:)`](/documentation/UIKit/UIView/sizeThatFits(_:)) and [`intrinsicContentSize`](/documentation/UIKit/UIView/intrinsicContentSize) don’t increase the calculated height for oversize characters. This is the default, standard behavior. Set [`sizingRule`](/documentation/UIKit/UILetterformAwareAdjusting/sizingRule) to [`UILetterformAwareSizingRule.typographic`](/documentation/UIKit/UILetterformAwareSizingRule/typographic) to use this behavior explicitly.

To adjust the boundary calculations in [`sizeThatFits(_:)`](/documentation/UIKit/UIView/sizeThatFits(_:)) and [`intrinsicContentSize`](/documentation/UIKit/UIView/intrinsicContentSize) to account for oversize characters, set [`sizingRule`](/documentation/UIKit/UILetterformAwareAdjusting/sizingRule) to [`UILetterformAwareSizingRule.oversize`](/documentation/UIKit/UILetterformAwareSizingRule/oversize). Note that the larger bounds to accommodate oversize characters may negatively impact typographic alignment, such as vertical edge alignment, vertical edge-to-edge spacing, or vertical centering.

## Topics

### Specifying text-sizing behavior

[`var sizingRule: UILetterformAwareSizingRule`](/documentation/UIKit/UILetterformAwareAdjusting/sizingRule)

The typographic bounds-sizing behavior that handles text with fonts that contain oversize characters.

[`enum UILetterformAwareSizingRule`](/documentation/UIKit/UILetterformAwareSizingRule)

Constants that specify typographic bounds-sizing behavior to handle text in fonts with oversize characters.

## Relationships

### Conforming Types

[`UISearchTextField`](/documentation/UIKit/UISearchTextField)

[`UILabel`](/documentation/UIKit/UILabel)

[`UITextField`](/documentation/UIKit/UITextField)

[`UITextView`](/documentation/UIKit/UITextView)

### Inherits From

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

---

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