Trait AppContext 

pub trait AppContext {
    // Required methods
    fn central(&mut self, f: &mut dyn FnMut(&mut dyn UiBuilder));
    fn set_theme(&mut self, theme: &UiTheme);
    fn set_fonts(&mut self, pack: &FontPack);
    fn screen_size(&self) -> [f32; 2];
    fn request_repaint(&mut self);

    // Provided methods
    fn pixels_per_point(&self) -> f32 { ... }
    fn request_close(&mut self) { ... }
}

Top-level app context — one per frame.

Required Methods

fn central(&mut self, f: &mut dyn FnMut(&mut dyn UiBuilder))

Open the central drawing region. The closure receives a &mut dyn UiBuilder and lays out the frame’s content.

Equivalent to “the whole window minus any panels installed at the backend level”. For tools without OS-level panels (the hub) this is the only call needed per frame.

fn set_theme(&mut self, theme: &UiTheme)

Apply a UiTheme to the underlying backend’s visual configuration. Idempotent — call again to swap palettes at runtime.

fn set_fonts(&mut self, pack: &FontPack)

Install the fonts described by pack. Called once at startup (or whenever fonts change).

fn screen_size(&self) -> [f32; 2]

Logical screen size in pixels — [width, height].

fn request_repaint(&mut self)

Ask the backend for another paint pass on the next available frame, even if no input event would normally trigger one. Use when an off-thread async task completes and the visible UI must update.

Provided Methods

fn pixels_per_point(&self) -> f32

Pixels-per-point ratio (DPI scale). 1.0 on standard displays, 2.0 on Retina, etc.

fn request_close(&mut self)

Request the application window to close. The shutdown happens at the end of the current frame (or whenever the backend gets to it).

Implementations on Foreign Types

impl AppContext for EguiAppContext<'_>

fn central(&mut self, f: &mut dyn FnMut(&mut dyn UiBuilder))

fn set_theme(&mut self, theme: &UiTheme)

fn set_fonts(&mut self, pack: &FontPack)

fn screen_size(&self) -> [f32; 2]

fn pixels_per_point(&self) -> f32

fn request_repaint(&mut self)

fn request_close(&mut self)

Implementors