Struct WindowBuilder 

pub struct WindowBuilder { /* private fields */ }

Builder for test windows.

let window = WindowBuilder::new()
    .title("Demo")
    .size(640.0, 480.0)
    .centered()
    .background_color(Color::gray(0.1))
    .build();

window.container().add_sublayer(&my_layer);
window.show_for(5.seconds());

Implementations

impl WindowBuilder

pub fn new() -> Self

Create a new window builder with default settings.

pub fn title(self, title: impl Into<String>) -> Self

Set the window title.

pub fn size(self, width: f64, height: f64) -> Self

Set the window size in points.

pub fn position(self, x: f64, y: f64) -> Self

Set the window position in screen coordinates. This is mutually exclusive with centered().

pub fn centered(self) -> Self

Center the window on the selected screen. This is mutually exclusive with position().

pub fn on_screen(self, screen: Screen) -> Self

Select which screen to place the window on. Defaults to Screen::Main.

pub fn background_color(self, color: impl Into<Color>) -> Self

Set the background color of the root container layer.

Accepts any type that implements Into<Color>, including:

• Color::RED, Color::rgb(0.1, 0.1, 0.2)
• Color::WHITE.with_alpha(0.5)

pub fn background_rgba(self, r: f64, g: f64, b: f64, a: f64) -> Self

Set the background color of the root container layer (RGBA, 0.0-1.0).

pub fn background_rgb(self, r: f64, g: f64, b: f64) -> Self

Set the background color of the root container layer (RGB with alpha=1.0).

pub fn style(self, style: WindowStyle) -> Self

Configure window style.

pub fn borderless(self) -> Self

Make the window borderless (no title bar, not resizable).

pub fn titled(self, titled: bool) -> Self

Set whether the window has a title bar.

pub fn closable(self, closable: bool) -> Self

Set whether the window is closable.

pub fn resizable(self, resizable: bool) -> Self

Set whether the window is resizable.

pub fn activation_policy(self, policy: NSApplicationActivationPolicy) -> Self

Set the application activation policy. Defaults to Accessory (no dock icon, no menu bar).

pub fn transparent(self) -> Self

Make the window fully transparent for overlay effects.

When enabled, this sets the NSWindow to be non-opaque with a clear background, allowing the content to be drawn on a fully transparent background. This is useful for creating floating overlay windows.

Example

use core_animation::prelude::*;

let window = WindowBuilder::new()
    .size(200.0, 200.0)
    .transparent()
    .borderless()
    .build();

pub fn corner_radius(self, radius: f64) -> Self

Set the corner radius on the container layer.

This applies rounded corners to the container layer that holds your content. Combine with .background_color() for a rounded panel effect.

Arguments

• radius - The corner radius in points

Example

use core_animation::prelude::*;

let window = WindowBuilder::new()
    .size(200.0, 200.0)
    .transparent()
    .borderless()
    .corner_radius(20.0)
    .background_color(Color::gray(0.1).with_alpha(0.85))
    .build();

pub fn level(self, level: WindowLevel) -> Self

Set the window level (z-order).

Controls where the window appears in the window stack relative to other windows. Higher levels appear above lower levels.

Arguments

• level - The window level to set

Example

use core_animation::prelude::*;

// Create an overlay that floats above all windows
let window = WindowBuilder::new()
    .size(200.0, 200.0)
    .level(WindowLevel::AboveAll)
    .build();

// Or use a custom level
let window = WindowBuilder::new()
    .level(WindowLevel::Custom(500))
    .build();

pub fn border_color(self, color: impl Into<Color>) -> Self

Set the border color on the container layer.

When set, this also applies a border width of 1.0 to the container layer. This creates a subtle visible border around the window content.

Arguments

• color - The border color

Example

use core_animation::prelude::*;

// Create a window with a subtle gray border
let window = WindowBuilder::new()
    .size(200.0, 200.0)
    .transparent()
    .borderless()
    .corner_radius(20.0)
    .background_color(Color::gray(0.1).with_alpha(0.85))
    .border_color(Color::rgba(0.3, 0.3, 0.35, 0.5))
    .build();

pub fn non_activating(self) -> Self

Make the window non-activating (won’t steal focus from other apps).

When enabled, showing the window will not make it the key window or activate the application. The previously focused app remains focused.

This is ideal for OSD-style overlays that should appear above other windows without interrupting the user’s workflow.

Example

use core_animation::prelude::*;

// Create an OSD that doesn't steal focus
let osd = WindowBuilder::new()
    .size(200.0, 80.0)
    .transparent()
    .borderless()
    .level(WindowLevel::ScreenSaver)
    .non_activating()
    .build();

osd.show_for(2.seconds()); // Shows without stealing focus

pub fn ignores_mouse_events(self) -> Self

Make the window ignore mouse events (click-through).

When enabled, mouse clicks pass through the window to whatever is behind it. Useful for pure display overlays.

Example

use core_animation::prelude::*;

// Create a click-through overlay
let overlay = WindowBuilder::new()
    .size(200.0, 80.0)
    .transparent()
    .borderless()
    .non_activating()
    .ignores_mouse_events()
    .build();

pub fn layer<F>(self, name: &str, configure: F) -> Self

where F: FnOnce(CAShapeLayerBuilder) -> CAShapeLayerBuilder,

Add a shape layer to the window.

The closure receives a CAShapeLayerBuilder for configuration. The built layer will be added to Window::container() when build() is called.

This allows configuring shape layers inline in the fluent API, creating a fully fluent flow from window to layers to animations.

Arguments

• name - A unique identifier for this layer
• configure - A closure that configures the layer builder

Examples

use core_animation::prelude::*;

let window = WindowBuilder::new()
    .title("Animation Demo")
    .size(400.0, 400.0)
    .centered()
    .transparent()
    .borderless()
    .background_color(Color::rgba(0.1, 0.1, 0.15, 0.85))
    .layer("circle", |s| {
        s.circle(80.0)
            .position(CGPoint::new(200.0, 200.0))
            .fill_color(Color::CYAN)
            .animate("pulse", KeyPath::TransformScale, |a| {
                a.values(0.85, 1.15)
                    .duration(2.seconds())
                    .autoreverses()
                    .repeat(Repeat::Forever)
            })
    })
    .build();

window.show_for(10.seconds());

Multiple layers can be added:

WindowBuilder::new()
    .size(400.0, 400.0)
    .layer("background_ring", |s| {
        s.circle(200.0)
            .position(CGPoint::new(200.0, 200.0))
            .fill_color(Color::TRANSPARENT)
            .stroke_color(Color::WHITE.with_alpha(0.3))
            .line_width(2.0)
    })
    .layer("main_circle", |s| {
        s.circle(80.0)
            .position(CGPoint::new(200.0, 200.0))
            .fill_color(Color::CYAN)
    })
    .build();

pub fn text_layer<F>(self, name: &str, configure: F) -> Self

where F: FnOnce(CATextLayerBuilder) -> CATextLayerBuilder,

Add a text layer to the window.

The closure receives a CATextLayerBuilder for configuration. The built layer will be added to Window::container() when build() is called.

Arguments

• name - A unique identifier for this layer
• configure - A closure that configures the text layer builder

Examples

use core_animation::prelude::*;

let window = WindowBuilder::new()
    .title("Text Demo")
    .size(400.0, 200.0)
    .centered()
    .transparent()
    .borderless()
    .background_color(Color::rgba(0.1, 0.1, 0.15, 0.85))
    .text_layer("label", |t| {
        t.text("Hello, World!")
            .font_size(24.0)
            .foreground_color(Color::WHITE)
            .alignment(TextAlign::Center)
            .position(CGPoint::new(200.0, 100.0))
    })
    .build();

window.show_for(5.seconds());

Combining text with shape layers:

WindowBuilder::new()
    .size(200.0, 100.0)
    .layer("background", |s| {
        s.circle(80.0)
            .position(CGPoint::new(50.0, 50.0))
            .fill_color(Color::BLUE)
    })
    .text_layer("label", |t| {
        t.text("85%")
            .font_size(16.0)
            .foreground_color(Color::WHITE)
            .position(CGPoint::new(150.0, 50.0))
    })
    .build();

pub fn build(self) -> Window

Build the window.

Panics

Panics if not called from the main thread.

Trait Implementations

impl Default for WindowBuilder

fn default() -> Self

Returns the “default value” for a type.