Makepad Platform Skill

Version: makepad-widgets (dev branch) | Last Updated: 2026-01-19

Check for updates: https://crates.io/crates/makepad-widgets

You are an expert at Makepad cross-platform development. Help users by:

• Understanding platforms: Explain supported platforms and backends
• Platform-specific code: Help with conditional compilation and platform APIs

When to Use

• You need to understand or target specific platforms and graphics backends in Makepad.
• The task involves platform compatibility, conditional compilation, or OS-specific behavior across desktop, mobile, or web.
• You need guidance on backend differences such as Metal, D3D11, OpenGL, WebGL, or platform modules.

Documentation

Refer to the local files for detailed documentation:

• ./references/platform-support.md - Platform details and OsType

IMPORTANT: Documentation Completeness Check

Before answering questions, Claude MUST:

1. Read the relevant reference file(s) listed above
2. If file read fails or file is empty:
   • Inform user: "本地文档不完整，建议运行 /sync-crate-skills makepad --force 更新文档"
   • Still answer based on SKILL.md patterns + built-in knowledge
3. If reference file exists, incorporate its content into the answer

Supported Platforms

OsType Enum

pub enum OsType {
    Unknown,
    Windows,
    Macos,
    Linux { custom_window_chrome: bool },
    Ios,
    Android(AndroidParams),
    OpenHarmony,
    Web(WebParams),
    OpenXR,
}

// Check platform in code
fn handle_event(&mut self, cx: &mut Cx, event: &Event) {
    match cx.os_type() {
        OsType::Macos => { /* macOS-specific */ }
        OsType::Windows => { /* Windows-specific */ }
        OsType::Web(_) => { /* Web-specific */ }
        _ => {}
    }
}

Platform Detection

// In Cx
impl Cx {
    pub fn os_type(&self) -> OsType;
    pub fn gpu_info(&self) -> &GpuInfo;
    pub fn xr_capabilities(&self) -> &XrCapabilities;
    pub fn cpu_cores(&self) -> usize;
}

Conditional Compilation

// Compile-time platform detection
#[cfg(target_os = "macos")]
fn macos_only() { }

#[cfg(target_os = "windows")]
fn windows_only() { }

#[cfg(target_os = "linux")]
fn linux_only() { }

#[cfg(target_arch = "wasm32")]
fn web_only() { }

#[cfg(target_os = "android")]
fn android_only() { }

#[cfg(target_os = "ios")]
fn ios_only() { }

Platform-Specific Features

Desktop (macOS/Windows/Linux)

• Window management (resize, minimize, maximize)
• File dialogs
• System menu
• Drag and drop
• Multiple monitors

Mobile (iOS/Android)

• Touch input
• Virtual keyboard
• Screen orientation
• App lifecycle (foreground/background)

Web (WebGL2)

• DOM integration
• Browser events
• Local storage
• HTTP requests

Entry Point

// App entry macro
app_main!(App);

pub struct App {
    ui: WidgetRef,
}

impl LiveRegister for App {
    fn live_register(cx: &mut Cx) {
        // Register components
        crate::makepad_widgets::live_design(cx);
    }
}

impl AppMain for App {
    fn handle_event(&mut self, cx: &mut Cx, event: &Event) {
        // Handle app events
        self.ui.handle_event(cx, event, &mut Scope::empty());
    }
}

When Answering Questions

1. Makepad compiles to native code for each platform (no runtime interpreter)
2. Shaders are compiled at build time for each graphics backend
3. Platform-specific code is in platform/src/os/ directory
4. Use cx.os_type() for runtime platform detection
5. Use #[cfg(target_os = "...")] for compile-time platform detection

Limitations

• Use this skill only when the task clearly matches the scope described above.
• Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
• Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.