SF Symbols — API Reference

When to Use This Skill

Use when:

• You need exact API signatures for rendering modes or symbol effects
• You need UIKit/AppKit equivalents for SwiftUI symbol APIs
• You need to check platform availability for a specific effect
• You need configuration options (weight, scale, variable values)
• You need to create custom symbols with proper template structure

Related Skills

• Use axiom-sf-symbols for decision trees, anti-patterns, troubleshooting, and when to use which effect
• Use axiom-swiftui-animation-ref for general SwiftUI animation (non-symbol)

Part 1: Symbol Display

SwiftUI

// Basic display
Image(systemName: "star.fill")

// With Label (icon + text)
Label("Favorites", systemImage: "star.fill")

// Font sizing — symbol scales with text
Image(systemName: "star.fill")
    .font(.title)

// Image scale — relative sizing without changing font
Image(systemName: "star.fill")
    .imageScale(.large) // .small, .medium, .large

// Explicit point size
Image(systemName: "star.fill")
    .font(.system(size: 24))

// Weight — matches SF Pro font weights
Image(systemName: "star.fill")
    .fontWeight(.bold) // .ultraLight through .black

// Symbol variant — programmatic .fill, .circle, .square, .slash
Image(systemName: "person")
    .symbolVariant(.circle.fill) // Renders person.circle.fill

// Variable value — 0.0 to 1.0, controls symbol fill level
Image(systemName: "speaker.wave.3.fill", variableValue: 0.5)

UIKit

// Basic display
let image = UIImage(systemName: "star.fill")
imageView.image = image

// Configuration — point size and weight
let config = UIImage.SymbolConfiguration(pointSize: 24, weight: .bold)
let image = UIImage(systemName: "star.fill", withConfiguration: config)

// Configuration — text style (scales with Dynamic Type)
let config = UIImage.SymbolConfiguration(textStyle: .title1)
let image = UIImage(systemName: "star.fill", withConfiguration: config)

// Configuration — scale
let config = UIImage.SymbolConfiguration(scale: .large) // .small, .medium, .large

// Combine configurations
let sizeConfig = UIImage.SymbolConfiguration(pointSize: 24, weight: .bold, scale: .large)

// Variable value
let image = UIImage(systemName: "speaker.wave.3.fill", variableValue: 0.5)

AppKit

// Basic display
let image = NSImage(systemSymbolName: "star.fill", accessibilityDescription: "Favorite")

// Configuration
let config = NSImage.SymbolConfiguration(pointSize: 24, weight: .bold)
let configured = image?.withSymbolConfiguration(config)

Part 2: Rendering Modes

SwiftUI

// Monochrome (default)
Image(systemName: "cloud.rain.fill")
    .foregroundStyle(.blue)

// Hierarchical — depth from single color
Image(systemName: "cloud.rain.fill")
    .symbolRenderingMode(.hierarchical)
    .foregroundStyle(.blue)

// Palette — explicit color per layer
Image(systemName: "cloud.rain.fill")
    .symbolRenderingMode(.palette)
    .foregroundStyle(.white, .blue)
// For 3-layer symbols:
    .foregroundStyle(.red, .white, .blue)

// Multicolor — Apple's curated colors
Image(systemName: "cloud.rain.fill")
    .symbolRenderingMode(.multicolor)

// Preferred rendering mode — uses symbol's preferred mode
// Falls back gracefully if the symbol doesn't support it
Image(systemName: "cloud.rain.fill")
    .symbolRenderingMode(.monochrome) // explicit monochrome

SymbolRenderingMode Enum

UIKit

// Hierarchical
let config = UIImage.SymbolConfiguration(hierarchicalColor: .systemBlue)
imageView.preferredSymbolConfiguration = config

// Palette
let config = UIImage.SymbolConfiguration(paletteColors: [.white, .systemBlue])
imageView.preferredSymbolConfiguration = config

// Multicolor
let config = UIImage.SymbolConfiguration.preferringMulticolor()
imageView.preferredSymbolConfiguration = config

// Monochrome — just set tintColor
imageView.tintColor = .systemBlue

Combining Configurations (UIKit)

let sizeConfig = UIImage.SymbolConfiguration(pointSize: 24, weight: .bold)
let colorConfig = UIImage.SymbolConfiguration(paletteColors: [.white, .blue, .gray])
let combined = sizeConfig.applying(colorConfig)
imageView.preferredSymbolConfiguration = combined

Part 3: Symbol Effects — Complete API

Effect Protocol Hierarchy

All symbol effects conform to SymbolEffect. Sub-protocols define behavior:

Remove All Effects (SwiftUI)

// Strip