ltk/examples/pickers.rs

//! `cargo run --example pickers`
//!
//! Showcases the four composition widgets added in this pass:
//! `notebook` (paginated tabs with a content area), `date_picker`,
//! `time_picker`, and `color_picker`. Each picker lives on its own
//! notebook page so the example doubles as a notebook demo.
//!
//! Esc exits.

use ltk::
{
	App, Element, Color, Keysym,
	column, text, scroll,
	notebook, date_picker, time_picker, color_picker,
	Date, Time,
};

#[ derive( Clone, Debug ) ]
enum Msg
{
	SelectTab( usize ),
	DateChanged( Date ),
	DateView( i32, u8 ),
	TimeChanged( Time ),
	ColorChanged( Color ),
}

struct PickerApp
{
	tab:        usize,
	date:       Date,
	view_year:  i32,
	view_month: u8,
	time:       Time,
	color:      Color,
}

impl PickerApp
{
	fn new() -> Self
	{
		let today = Date::new( 2026, 5, 2 );
		Self
		{
			tab:        0,
			date:       today,
			view_year:  today.year,
			view_month: today.month,
			time:       Time::new( 9, 30 ),
			color:      Color::hex( 0x14, 0xB8, 0xA6 ),
		}
	}

	fn date_page( &self ) -> Element<Msg>
	{
		let primary = ltk::theme_palette().text_primary;
		let summary = format!(
			"Selected: {}-{:02}-{:02}",
			self.date.year, self.date.month, self.date.day,
		);
		column::<Msg>()
			.padding( 0.0 )
			.spacing( 16.0 )
			.push( text( summary ).size( 14.0 ).color( primary ) )
			.push(
				date_picker( self.date )
					.view( self.view_year, self.view_month )
					.today( Date::new( 2026, 5, 2 ) )
					.on_change( Msg::DateChanged )
					.on_navigate( Msg::DateView )
			)
			.into()
	}

	fn time_page( &self ) -> Element<Msg>
	{
		let primary = ltk::theme_palette().text_primary;
		let summary = format!(
			"Selected: {:02}:{:02}",
			self.time.hour, self.time.minute,
		);
		column::<Msg>()
			.padding( 0.0 )
			.spacing( 16.0 )
			.push( text( summary ).size( 14.0 ).color( primary ) )
			.push(
				time_picker( self.time )
					.minute_step( 1 )
					.twelve_hour( true )
					.on_change( Msg::TimeChanged )
			)
			.into()
	}

	fn color_page( &self ) -> Element<Msg>
	{
		let primary = ltk::theme_palette().text_primary;
		let summary = format!(
			"R={:.2} G={:.2} B={:.2} A={:.2}",
			self.color.r, self.color.g, self.color.b, self.color.a,
		);
		column::<Msg>()
			.padding( 0.0 )
			.spacing( 16.0 )
			.push( text( summary ).size( 14.0 ).color( primary ) )
			.push(
				color_picker( self.color )
					.show_alpha( true )
					.on_change( Msg::ColorChanged )
			)
			.into()
	}
}

impl App for PickerApp
{
	type Message = Msg;

	fn app_id( &self ) -> &str { "net.liberux.ltk.example.pickers" }
	fn save_state( &self ) -> Option<Vec<u8>> { None }
	fn restore_state( &mut self, _state: Vec<u8> ) {}

	fn view( &self ) -> Element<Msg>
	{
		let header = text( "ltk pickers" )
			.size( 24.0 )
			.color( ltk::theme_palette().text_primary )
			.align_center();

		let body = column::<Msg>()
			.padding( 24.0 )
			.spacing( 16.0 )
			.push( header )
			.push(
				notebook::<Msg>()
					.page( "Date",  self.date_page() )
					.page( "Time",  self.time_page() )
					.page( "Color", self.color_page() )
					.selected( self.tab )
					.on_select( Msg::SelectTab )
			);

		// Wrap in a scroll so the calendar's 6×7 grid fits even on
		// modest window heights.
		scroll( body ).into()
	}

	fn update( &mut self, msg: Msg )
	{
		match msg
		{
			Msg::SelectTab( i )       => self.tab = i,
			Msg::DateChanged( d )     => { self.date = d; self.view_year = d.year; self.view_month = d.month; }
			Msg::DateView( y, m )     => { self.view_year = y; self.view_month = m; }
			Msg::TimeChanged( t )     => self.time = t,
			Msg::ColorChanged( c )    => self.color = c,
		}
	}

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

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