Add arc widget

examples/Cargo.toml

@@ -26,3 +26,7 @@ path = "button_click.rs"
 [[example]]
 name = "gauge"
 path = "gauge.rs"
+
+[[example]]
+name = "arc"
+path = "arc.rs"

examples/arc.rs

@@ -0,0 +1,103 @@
+use embedded_graphics::pixelcolor::Rgb565;
+use embedded_graphics::prelude::*;
+use embedded_graphics_simulator::{
+    OutputSettingsBuilder, SimulatorDisplay, SimulatorEvent, Window,
+};
+use lvgl::style::Style;
+use lvgl::widgets::{Arc, ArcPart, Label, LabelAlign};
+use lvgl::Widget;
+use lvgl::{self, Align, Color, DisplayDriver, Event, Part, State, UI};
+use lvgl_sys;
+use std::sync::{mpsc, Arc as StdArc, Mutex};
+use std::thread::sleep;
+use std::time::Duration;
+
+fn main() -> Result<(), String> {
+    let mut display: SimulatorDisplay<Rgb565> = SimulatorDisplay::new(Size::new(
+        lvgl_sys::LV_HOR_RES_MAX,
+        lvgl_sys::LV_VER_RES_MAX,
+    ));
+
+    let output_settings = OutputSettingsBuilder::new().scale(2).build();
+    let mut window = Window::new("Arc Example", &output_settings);
+
+    let mut ui = UI::init().unwrap();
+
+    // Implement and register your display:
+    let display_driver = DisplayDriver::new(&mut display);
+    ui.disp_drv_register(display_driver);
+
+    // Create screen and widgets
+    let mut screen = ui.scr_act();
+
+    let mut screen_style = Style::default();
+    screen_style.set_bg_color(State::DEFAULT, Color::from_rgb((255, 255, 255)));
+    screen_style.set_radius(State::DEFAULT, 0);
+    screen.add_style(Part::Main, screen_style);
+
+    // Create the arc object
+    let mut arc = Arc::new(&mut screen);
+    arc.set_size(150, 150);
+    arc.set_align(&mut screen, Align::Center, 0, 10);
+    arc.set_start_angle(135, ArcPart::Indicator);
+    arc.set_end_angle(135, ArcPart::Indicator);
+
+    let mut loading_lbl = Label::new(&mut screen);
+    loading_lbl.set_text("Loading...");
+    loading_lbl.set_align(&mut arc, Align::OutTopMid, 0, -10);
+    loading_lbl.set_label_align(LabelAlign::Center);
+
+    let mut loading_style = Style::default();
+    loading_style.set_text_color(State::DEFAULT, Color::from_rgb((0, 0, 0)));
+    loading_lbl.add_style(Part::Main, loading_style);
+
+    let threaded_ui = StdArc::new(Mutex::new(ui));
+
+    let (stop_ch, read_ch) = mpsc::channel();
+    let closure_ui = threaded_ui.clone();
+    let tick_thr = std::thread::spawn(move || loop {
+        let period = Duration::from_millis(10);
+        closure_ui.lock().unwrap().tick_inc(period);
+
+        sleep(period);
+        if read_ch.try_recv().is_ok() {
+            break;
+        }
+    });
+
+    let mut angle = 0;
+    let mut forward = true;
+
+    let mut i = 0;
+    'running: loop {
+        if i > 270 {
+            forward = if forward { false } else { true };
+            i = 1;
+            threaded_ui
+                .lock()
+                .unwrap()
+                .event_send(&mut loading_lbl, Event::Clicked)
+        }
+        angle = if forward { angle + 1 } else { angle - 1 };
+        arc.set_end_angle(angle + 135, ArcPart::Indicator);
+        i += 1;
+
+        sleep(Duration::from_millis(10));
+
+        threaded_ui.lock().unwrap().task_handler();
+
+        window.update(&display);
+
+        for event in window.events() {
+            match event {
+                SimulatorEvent::Quit => break 'running,
+                _ => {}
+            }
+        }
+    }
+
+    stop_ch.send(true).unwrap();
+    tick_thr.join().unwrap();
+
+    Ok(())
+}

lvgl/src/widgets/arc.rs

@@ -0,0 +1,56 @@
+use crate::NativeObject;
+
+define_object!(Arc, lv_arc_create, part = ArcPart);
+
+impl Arc {
+    /// Set the start angle, for the given arc part.
+    /// 0 degrees for the right, 90 degrees for the bottom, etc.
+    pub fn set_start_angle(&mut self, angle: u16, part: ArcPart) {
+        match part {
+            ArcPart::Background => unsafe {
+                lvgl_sys::lv_arc_set_bg_start_angle(self.core.raw().as_mut(), angle)
+            },
+            ArcPart::Indicator => unsafe {
+                lvgl_sys::lv_arc_set_start_angle(self.core.raw().as_mut(), angle)
+            },
+        }
+    }
+
+    /// Set the end angle, for the given arc part.
+    /// 0 degrees for the right, 90 degrees for the bottom, etc.
+    pub fn set_end_angle(&mut self, angle: u16, part: ArcPart) {
+        match part {
+            ArcPart::Background => unsafe {
+                lvgl_sys::lv_arc_set_bg_start_angle(self.core.raw().as_mut(), angle)
+            },
+            ArcPart::Indicator => unsafe {
+                lvgl_sys::lv_arc_set_end_angle(self.core.raw().as_mut(), angle)
+            },
+        }
+    }
+
+    /// Rotate the arc, `angle` degrees clockwise.
+    pub fn set_rotation(&mut self, angle: u16) {
+        unsafe {
+            lvgl_sys::lv_arc_set_rotation(self.core.raw().as_mut(), angle);
+        }
+    }
+}
+
+/// The different parts, of an arc object.
+pub enum ArcPart {
+    /// The background of the arc.
+    Background,
+    /// The indicator of the arc.
+    /// This is what moves/changes, depending on the arc's value.
+    Indicator,
+}
+
+impl From<ArcPart> for u8 {
+    fn from(component: ArcPart) -> Self {
+        match component {
+            ArcPart::Background => lvgl_sys::LV_ARC_PART_BG as u8,
+            ArcPart::Indicator => lvgl_sys::LV_ARC_PART_INDIC as u8,
+        }
+    }
+}

lvgl/src/widgets/mod.rs

@@ -1,9 +1,11 @@
+mod arc;
 mod bar;
 mod btn;
 mod gauge;
 mod label;
 
-pub use self::bar::*;
-pub use self::btn::*;
-pub use self::gauge::*;
-pub use self::label::*;
+pub use arc::*;
+pub use bar::*;
+pub use btn::*;
+pub use gauge::*;
+pub use label::*;