SwiftyMarkdown

SwiftyMarkdown is a library that converts Markdown files and strings into NSAttributedStrings. It uses sensible defaults and a Swift-style syntax. It leverages dynamic type to ensure font sizes are set correctly based on the font you choose.

Key features include:

• Support for Dark Mode out of the box (uses system color .label on iOS 13+).
• Support for images stored in the app bundle using the syntax ![Image](<Name In bundle>).
• Support for codeblocks, blockquotes, and unordered lists.
• Paragraph alignment for line-level attributes (e.g., h2.alignment = .center).
• Option to underline links by setting underlineLinks = true.

SwiftyMarkdown supports a wide range of standard Markdown syntax, including:

• Emphasis: *italics* or _italics_, **bold** or __bold__, and ~~strikethrough~~.
• Code: Inline `code` and indented code blocks.
• Headers: # Header 1 (or using underlines like ====) through ###### Header 6.
• Links & Images: [Links](url) and bundle images ![Images](<Name of asset in bundle>).
• Blockquotes: > Blockquotes.
• Lists:
  • Unordered (bulleted) lists with up to three levels of indentation.
  • Ordered (numbered) lists with up to three levels of indentation.

SwiftyMarkdown uses a two-step processing engine that is not limited to Markdown; you can use it to define custom syntax for any text-based styling.

1. Line Processing: Rules are processed from top to bottom. Line tags (like headings or code blocks) are identified first.
2. Character Styling: After lines are processed, character rules are applied to the text to handle inline styles (like bold or italic).

To implement custom logic, you define a LineStyling enum for line-level rules and a CharacterStyling enum for character-level rules, then provide them to a SwiftyLineProcessor or SwiftyTokeniser.

You can integrate SwiftyMarkdown into your Xcode project using either CocoaPods or Swift Package Manager (SPM).

CocoaPods Add the following to your Podfile: pod 'SwiftyMarkdown'

Swift Package Manager (SPM) In Xcode, navigate to File -> Swift Packages -> Add Package Dependency and provide the GitHub URL for the repository.

Before using fastlane, ensure you have the latest version of the Xcode command line tools installed on your system.

xcode-select --install

You can use SwiftyTokeniser to parse custom syntax. For example, to apply a custom .elf style to text wrapped in % characters:

1. Define a CharacterStyling enum.
2. Create a CharacterRule with the % tag set to .repeating.
3. Process the string using SwiftyTokeniser.

enum Characters : CharacterStyling {
	case elf

	func isEqualTo( _ other : CharacterStyling) -> Bool {
		if let other = other as? Characters {
			return other == self
		}
		return false
	}
}

let characterRules = [
	CharacterRule(primaryTag: CharacterRuleTag(tag: "%", type: .repeating), otherTags: [], styles: [1 : CharacterStyle.elf])
]

let processor = SwiftyTokeniser( with : characterRules )
let string = "The elf will speak now: %Here is my elf speaking%"
let tokens = processor.process(string)

Since SKLabelNode supports attributed text, you can render Markdown directly into a label by converting the parsed Markdown into an NSAttributedString.

let smd = SwiftyMarkdown(string: "My Character's **Dialogue**")

let label = SKLabelNode()
label.preferredMaxLayoutWidth = 500
label.numberOfLines = 0
label.attributedText = smd.attributedString()

You can customize the appearance of specific Markdown elements (like code blocks or headers) by setting properties on the Markdown instance. Supported properties include fontName, color, and alignment for various element types.

md.code.fontName = "CourierNewPSMT"

md.h2.fontName = "AvenirNextCondensed-Medium"
md.h2.color = UIColor.redColor()
md.h2.alignment = .center

SwiftyMarkdown allows you to customize the appearance of different Markdown elements (headers, body, italics, etc.) using dot syntax. You can modify font names, colors, font sizes, and alignments.

Note: On iOS, specified font sizes are adjusted relative to the user's dynamic type settings. Line-level attributes like headers support paragraph alignment (e.g., .center).

md.body.fontName = "AvenirNextCondensed-Medium"

md.h1.color = UIColor.redColor()
md.h1.fontName = "AvenirNextCondensed-Bold"
md.h1.fontSize = 16
md.h1.alignmnent = .center

md.italic.color = UIColor.blueColor()

md.underlineLinks = true

md.bullet = "🍏"