First commit. Version 0.1.0

examples/sliders.rs

@@ -0,0 +1,155 @@
+//! `cargo run --example sliders`
+//!
+//! Showcases the **Glass** effect on both axes of the slider widget. The
+//! horizontal `slider` at the top and the two vertical `vslider` pills
+//! below share the same composite surface — outer glow + four inset
+//! shadows (two `PlusLighter` light-catchers, one `Overlay` rim, one
+//! soft dark contact shadow) — over a translucent white-to-grey track
+//! and a flat cyan accent fill.
+//!
+//! Drag or tap anywhere inside the controls to change their values; Esc
+//! exits.
+//!
+//! NOTE: ltk is a Wayland layer-shell toolkit. This example requires a
+//! running Wayland compositor (e.g. sway, labwc, or a full desktop
+//! session). The Glass effect is rendered by the GPU (GLES2) backend —
+//! the software backend falls back to a flat fill.
+
+use ltk::
+{
+	App, Element, Color, Keysym,
+	column, row, text, spacer, slider, vslider,
+};
+
+#[ derive( Clone ) ]
+enum Msg
+{
+	SetHue( f32 ),
+	SetVolume( f32 ),
+	SetBrightness( f32 ),
+}
+
+struct SlidersApp
+{
+	hue:        f32,
+	volume:     f32,
+	brightness: f32,
+}
+
+impl SlidersApp
+{
+	fn new() -> Self
+	{
+		Self { hue: 0.30, volume: 0.48, brightness: 0.92 }
+	}
+}
+
+impl App for SlidersApp
+{
+	type Message = Msg;
+
+	fn view( &self ) -> Element<Msg>
+	{
+		// Pill dimensions chosen so the Glass insets read at their
+		// intended proportions. The insets (0.45–3.6 px offsets,
+		// 0.9–13.5 px blur radii) are absolute, so smaller pills
+		// produce relatively tighter highlights.
+		const PILL_W: f32 =  80.0;
+		const PILL_H: f32 = 176.0;
+
+		// Track text against the active theme so switching to dark mode
+		// (via `ltk::set_active_mode`) flips the labels automatically.
+		let palette   = ltk::theme_palette();
+		let primary   = palette.text_primary;
+		let secondary = palette.text_secondary;
+
+		// Horizontal slider — claims its row's full width.
+		let hue_slider = slider( self.hue ).on_change( Msg::SetHue );
+
+		// Two vertical pills.
+		let brgt = vslider( self.brightness ).size( PILL_W, PILL_H ).on_change( Msg::SetBrightness );
+		let vol  = vslider( self.volume     ).size( PILL_W, PILL_H ).on_change( Msg::SetVolume     );
+
+		let pills = row::<Msg>()
+			.spacing( 40.0 )
+			.padding( 0.0 )
+			.push( brgt )
+			.push( vol );
+
+		let pill_labels = row::<Msg>()
+			.spacing( 40.0 )
+			.padding( 0.0 )
+			.push(
+				text( format!( "Brightness {:>3.0}%", self.brightness * 100.0 ) )
+					.size( 14.0 )
+					.color( primary ),
+			)
+			.push(
+				text( format!( "Volume {:>3.0}%", self.volume * 100.0 ) )
+					.size( 14.0 )
+					.color( primary ),
+			);
+
+		column::<Msg>()
+			.padding( 32.0 )
+			.spacing( 16.0 )
+			.center_y( true )
+			.push(
+				text( "ltk — Glass sliders, both axes" )
+					.size( 24.0 )
+					.color( primary )
+					.align_center(),
+			)
+			.push( spacer() )
+			.push(
+				text( format!( "Hue {:>3.0}%", self.hue * 100.0 ) )
+					.size( 14.0 )
+					.color( primary ),
+			)
+			.push( hue_slider )
+			.push( spacer() )
+			.push( pills )
+			.push( pill_labels )
+			.push( spacer() )
+			.push(
+				text( "Drag or tap inside a control  ·  Esc = quit" )
+					.size( 12.0 )
+					.color( secondary )
+					.align_center(),
+			)
+			.into()
+	}
+
+	fn update( &mut self, msg: Msg )
+	{
+		match msg
+		{
+			Msg::SetHue( v )        => self.hue        = v,
+			Msg::SetVolume( v )     => self.volume     = v,
+			Msg::SetBrightness( v ) => self.brightness = v,
+		}
+	}
+
+	fn on_key( &mut self, keysym: Keysym ) -> Option<Msg>
+	{
+		if keysym == Keysym::Escape
+		{
+			std::process::exit( 0 );
+		}
+		None
+	}
+
+	// Track the active theme's background so the Glass highlights and
+	// the translucent track read correctly against it, and dark-mode
+	// runs (via `ltk::set_active_mode(ThemeMode::Dark)`) flip
+	// automatically.
+	fn background_color( &self ) -> Color
+	{
+		ltk::theme_palette().bg
+	}
+}
+
+fn main()
+{
+	ltk::run( SlidersApp::new() );
+}