ltk/examples/widgets.rs

use std::time::Instant;

use ltk::{
	App, Element, Keysym, WidgetId,
	column, row, text, text_edit, spacer, separator, slider,
	toggle, checkbox, radio, progress_bar, scroll,
	spinner, tabs,
};

#[derive( Clone )]
enum Msg
{
	ToggleWifi,
	ToggleBluetooth,
	ToggleDarkMode,
	CheckNotifications,
	CheckUpdates,
	SelectThemeLight,
	SelectThemeDark,
	SelectThemeAuto,
	SliderChanged( f32 ),
	SelectTab( usize ),
	NoteChanged( String ),
	Tick,
}

struct WidgetsApp
{
	wifi:          bool,
	bluetooth:     bool,
	dark_mode:     bool,
	notifications: bool,
	updates:       bool,
	theme:         usize,
	progress:      f32,
	volume:        f32,
	tab:           usize,
	note:          String,
	started_at:    Instant,
}

impl WidgetsApp
{
	fn new() -> Self
	{
		Self
		{
			wifi:          true,
			bluetooth:     false,
			dark_mode:     true,
			notifications: true,
			updates:       false,
			theme:         2,
			progress:      0.65,
			volume:        0.7,
			tab:           0,
			note:          String::new(),
			started_at:    Instant::now(),
		}
	}
}

impl App for WidgetsApp
{
	type Message = Msg;

	fn view( &self ) -> Element<Msg>
	{
		// Pull text colours from the active theme so the example
		// reads correctly under both light and dark mode without
		// touching the example code.
		let palette   = ltk::theme_palette();
		let primary   = palette.text_primary;
		let secondary = palette.text_secondary;

		let title = text( "ltk widgets" ).size( 24.0 ).color( primary ).align_center();

		// Segmented tab strip — selection just rendered as a banner below.
		let tabs_strip: Element<Msg> = tabs( [ "General", "Audio", "Network" ] )
			.selected( self.tab )
			.on_select( Msg::SelectTab )
			.into();
		let tab_label = format!(
			"Active tab: {}",
			[ "General", "Audio", "Network" ][ self.tab.min( 2 ) ],
		);

		let toggles = column::<Msg>()
			.spacing( 0.0 )
			.push( text( "Toggle" ).size( 13.0 ).color( secondary ) )
			.push( toggle( self.wifi ).label( "Wi-Fi" ).on_toggle( Msg::ToggleWifi ) )
			.push( toggle( self.bluetooth ).label( "Bluetooth" ).on_toggle( Msg::ToggleBluetooth ) )
			.push( toggle( self.dark_mode ).label( "Dark mode" ).on_toggle( Msg::ToggleDarkMode ) );

		let checkboxes = column::<Msg>()
			.spacing( 0.0 )
			.push( text( "Checkbox" ).size( 13.0 ).color( secondary ) )
			.push( checkbox( self.notifications ).label( "Notifications" ).on_toggle( Msg::CheckNotifications ) )
			.push( checkbox( self.updates ).label( "Auto updates" ).on_toggle( Msg::CheckUpdates ) );

		let radios = column::<Msg>()
			.spacing( 0.0 )
			.push( text( "Radio" ).size( 13.0 ).color( secondary ) )
			.push( radio( self.theme == 0 ).label( "Light" ).on_select( Msg::SelectThemeLight ) )
			.push( radio( self.theme == 1 ).label( "Dark" ).on_select( Msg::SelectThemeDark ) )
			.push( radio( self.theme == 2 ).label( "Auto" ).on_select( Msg::SelectThemeAuto ) );

		let vol_label = format!( "Volume: {:.0}%", self.volume * 100.0 );
		let prog_label = format!( "Progress: {:.0}%", self.progress * 100.0 );

		// Spinner — animation phase derived from the wall clock so the
		// arc rotates at one revolution per second.
		let phase = self.started_at.elapsed().as_secs_f32();
		let spin_row: Element<Msg> = row::<Msg>()
			.spacing( 12.0 )
			.push( spinner().phase( phase ) )
			.push( text( "Loading…" ).size( 14.0 ).color( primary ) )
			.into();

		// Multiline text area — Enter inserts a newline, Tab leaves it.
		let textarea = text_edit( "Type a note (multi-line)", &self.note )
			.multiline( true )
			.rows( 4 )
			.id( WidgetId( "widgets/note" ) )
			.on_change( Msg::NoteChanged );

		let content = column::<Msg>()
			.padding( 32.0 )
			.spacing( 12.0 )
			.push( title )
			.push( tabs_strip )
			.push( text( tab_label ).size( 13.0 ).color( secondary ) )
			.push( separator() )
			.push( toggles )
			.push( separator() )
			.push( checkboxes )
			.push( separator() )
			.push( radios )
			.push( separator() )
			.push( text( vol_label ).size( 13.0 ).color( secondary ) )
			.push( slider( self.volume ).on_change( Msg::SliderChanged ) )
			.push( text( prog_label ).size( 13.0 ).color( secondary ) )
			.push( progress_bar( self.progress ) )
			.push( separator() )
			.push( text( "Spinner" ).size( 13.0 ).color( secondary ) )
			.push( spin_row )
			.push( separator() )
			.push( text( "Multiline text edit" ).size( 13.0 ).color( secondary ) )
			.push( textarea )
			.push( spacer() )
			.push(
				text( "Esc = quit" )
					.size( 12.0 )
					.color( secondary )
					.align_center(),
			);

		scroll( content ).into()
	}

	fn update( &mut self, msg: Msg )
	{
		match msg
		{
			Msg::ToggleWifi          => self.wifi = !self.wifi,
			Msg::ToggleBluetooth     => self.bluetooth = !self.bluetooth,
			Msg::ToggleDarkMode      => self.dark_mode = !self.dark_mode,
			Msg::CheckNotifications  => self.notifications = !self.notifications,
			Msg::CheckUpdates        => self.updates = !self.updates,
			Msg::SelectThemeLight    => self.theme = 0,
			Msg::SelectThemeDark     => self.theme = 1,
			Msg::SelectThemeAuto     => self.theme = 2,
			Msg::SliderChanged( v )  => self.volume = v,
			Msg::SelectTab( i )      => self.tab = i,
			Msg::NoteChanged( s )    => self.note = s,
			Msg::Tick                => {}
		}
	}

	fn on_key( &mut self, keysym: Keysym ) -> Option<Msg>
	{
		if keysym == Keysym::Escape { std::process::exit( 0 ); }
		None
	}

	// Drive the spinner — the runtime keeps redrawing while this returns
	// `true`, and `view()` reads the wall clock to compute the phase, so
	// no explicit Tick message is even needed for the visual to advance.
	fn is_animating( &self ) -> bool { true }

	fn poll_interval( &self ) -> Option<std::time::Duration>
	{
		// Suppress the dead-code warning on Msg::Tick; a real app would
		// also use the timer to drive non-visual periodic work here.
		Some( std::time::Duration::from_millis( 250 ) )
	}

	fn poll_external( &mut self ) -> Vec<Msg>
	{
		// Consumed: the timer above keeps the runtime warm, but the
		// spinner reads the wall clock directly so no Tick is required.
		// We still emit one occasionally so the message variant is
		// exercised — keeps the example honest about the pattern apps
		// usually use for clock work.
		if self.started_at.elapsed().as_millis() % 1_000 < 250
		{
			vec![ Msg::Tick ]
		} else {
			vec![]
		}
	}
}

fn main()
{
	ltk::run( WidgetsApp::new() );
}