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# NSMutableParagraphStyle

An object for changing the values of the subattributes in a paragraph style attribute.

```
class NSMutableParagraphStyle
```

## Overview

The [`NSMutableParagraphStyle`](/documentation/UIKit/NSMutableParagraphStyle) class adds methods to its superclass, [`NSParagraphStyle`](/documentation/UIKit/NSParagraphStyle), for changing the values of the subattributes in a paragraph style attribute. For more information, see [`NSParagraphStyle`](/documentation/UIKit/NSParagraphStyle) and <doc://com.apple.documentation/documentation/Foundation/NSAttributedString>.

> Important:
> Don’t mutate a paragraph style object after adding it to an attributed string. Doing so can cause your app to crash.

## Topics

### Setting style information

[`setParagraphStyle(_:)`](/documentation/UIKit/NSMutableParagraphStyle/setParagraphStyle(_:))

Replaces the subattributes of the paragraph with those in the specified paragraph style object.

[`alignment`](/documentation/UIKit/NSMutableParagraphStyle/alignment)

The text alignment of the paragraph.

[`firstLineHeadIndent`](/documentation/UIKit/NSMutableParagraphStyle/firstLineHeadIndent)

The indentation of the first line of the paragraph.

[`headIndent`](/documentation/UIKit/NSMutableParagraphStyle/headIndent)

The indentation of the paragraph’s lines other than the first.

[`tailIndent`](/documentation/UIKit/NSMutableParagraphStyle/tailIndent)

The trailing indentation of the paragraph.

[`lineHeightMultiple`](/documentation/UIKit/NSMutableParagraphStyle/lineHeightMultiple)

The line height multiple.

[`maximumLineHeight`](/documentation/UIKit/NSMutableParagraphStyle/maximumLineHeight)

The paragraph’s maximum line height.

[`minimumLineHeight`](/documentation/UIKit/NSMutableParagraphStyle/minimumLineHeight)

The paragraph’s minimum line height.

[`lineSpacing`](/documentation/UIKit/NSMutableParagraphStyle/lineSpacing)

The distance in points between the bottom of one line fragment and the top of the next.

[`paragraphSpacing`](/documentation/UIKit/NSMutableParagraphStyle/paragraphSpacing)

The space after the end of the paragraph.

[`paragraphSpacingBefore`](/documentation/UIKit/NSMutableParagraphStyle/paragraphSpacingBefore)

The distance between the paragraph’s top and the beginning of its text content.

[`baseWritingDirection`](/documentation/UIKit/NSMutableParagraphStyle/baseWritingDirection)

The base writing direction for the paragraph.

### Specifying tab information

[`addTabStop(_:)`](/documentation/UIKit/NSMutableParagraphStyle/addTabStop(_:))

Adds the specified tab stop to the paragraph.

[`removeTabStop(_:)`](/documentation/UIKit/NSMutableParagraphStyle/removeTabStop(_:))

Removes the first text tab with a location and type equal to the specified tab stop.

[`tabStops`](/documentation/UIKit/NSMutableParagraphStyle/tabStops)

The text tab objects that represent the paragraph’s tab stops.

[`defaultTabInterval`](/documentation/UIKit/NSMutableParagraphStyle/defaultTabInterval)

A number used as the document’s default tab spacing.

### Setting text blocks and lists

  <doc://com.apple.documentation/documentation/AppKit/NSMutableParagraphStyle/textBlocks>

[`textLists`](/documentation/UIKit/NSMutableParagraphStyle/textLists)

The text lists that contain the paragraph.

### Setting line-break information

[`lineBreakMode`](/documentation/UIKit/NSMutableParagraphStyle/lineBreakMode)

The mode for breaking lines in the paragraph.

[`lineBreakStrategy`](/documentation/UIKit/NSMutableParagraphStyle/lineBreakStrategy)

The strategies that the text system may use to break lines while laying out the paragraph.

[`hyphenationFactor`](/documentation/UIKit/NSMutableParagraphStyle/hyphenationFactor)

The paragraph’s threshold for hyphenation.

[`usesDefaultHyphenation`](/documentation/UIKit/NSMutableParagraphStyle/usesDefaultHyphenation)

  <doc://com.apple.documentation/documentation/AppKit/NSMutableParagraphStyle/tighteningFactorForTruncation>

[`allowsDefaultTighteningForTruncation`](/documentation/UIKit/NSMutableParagraphStyle/allowsDefaultTighteningForTruncation)

A Boolean value that indicates whether the system tightens intercharacter spacing before truncating text.

### Setting HTML header level

  <doc://com.apple.documentation/documentation/AppKit/NSMutableParagraphStyle/headerLevel>


---

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