Struct AppConfig 

#[repr(C)]
pub struct AppConfig {
    pub log_level: AppLogLevel,
    pub enable_visual_panic_hook: bool,
    pub enable_logging_on_panic: bool,
    pub enable_tab_navigation: bool,
    pub termination_behavior: AppTerminationBehavior,
    pub icon_provider: IconProviderHandle,
    pub bundled_fonts: NamedFontVec,
    pub font_loading: FontLoadingConfig,
    pub mock_css_environment: OptionCssMockEnvironment,
    pub system_style: SystemStyle,
}

Configuration for optional features, such as whether to enable logging or panic hooks

Fields

log_level: AppLogLevel

If enabled, logs error and info messages.

Default is LevelFilter::Error to log all errors by default

enable_visual_panic_hook: bool

If the app crashes / panics, a window with a message box pops up. Setting this to false disables the popup box.

enable_logging_on_panic: bool

If this is set to true (the default), a backtrace + error information gets logged to stdout and the logging file (only if logging is enabled).

enable_tab_navigation: bool

(STUB) Whether keyboard navigation should be enabled (default: true). Currently not implemented.

termination_behavior: AppTerminationBehavior

Determines what happens when all windows are closed. Default: EndProcess (terminate when last window closes).

icon_provider: IconProviderHandle

Icon provider for the application. Register icons here before calling App::run(). Each window will clone this provider (cheap, Arc-based).

bundled_fonts: NamedFontVec

Fonts bundled with the application. These fonts are loaded into memory and take priority over system fonts.

font_loading: FontLoadingConfig

Configuration for how system fonts should be loaded. Default: LoadAllSystemFonts (scan all system fonts at startup)

mock_css_environment: OptionCssMockEnvironment

Optional mock environment for CSS evaluation.

When set, this overrides the auto-detected system properties (OS, theme, etc.) for CSS @-rules and dynamic selectors. This is useful for:

• Testing OS-specific styles on a different platform
• Screenshot testing with consistent environment
• Previewing how the app looks on different systems

Default: None (use auto-detected system properties)

system_style: SystemStyle

System style detected at startup (theme, colors, fonts, etc.)

This is detected once at AppConfig::create() and passed to all windows. You can override this after creation to use a custom system style, for example to test how your app looks on a different platform.

Implementations

impl AppConfig

pub fn create() -> Self

pub fn with_mock_environment(self, env: CssMockEnvironment) -> Self

Create config with a mock CSS environment for testing

This allows you to simulate how your app would look on a different OS, with a different theme, language, or accessibility settings.

Example

let config = AppConfig::create()
    .with_mock_environment(CssMockEnvironment {
        os: OptionOsCondition::Some(OsCondition::Linux),
        theme: OptionThemeCondition::Some(ThemeCondition::Dark),
        ..Default::default()
    });

Trait Implementations

impl Clone for AppConfig

fn clone(&self) -> AppConfig

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for AppConfig

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for AppConfig

fn default() -> Self

Returns the “default value” for a type.