Merge pull request #2331 from iced-rs/program-api

`Program` API

README.md

@@ -98,8 +98,8 @@ that can be incremented and decremented using two buttons.
 We start by modelling the __state__ of our application:
 
 ```rust
+#[derive(Default)]
 struct Counter {
-    // The counter value
     value: i32,
 }
 ```
@@ -110,8 +110,8 @@ the button presses. These interactions are our __messages__:
 ```rust
 #[derive(Debug, Clone, Copy)]
 pub enum Message {
-    IncrementPressed,
-    DecrementPressed,
+    Increment,
+    Decrement,
 }
 ```
 
@@ -126,15 +126,15 @@ impl Counter {
         // We use a column: a simple vertical layout
         column![
             // The increment button. We tell it to produce an
-            // `IncrementPressed` message when pressed
-            button("+").on_press(Message::IncrementPressed),
+            // `Increment` message when pressed
+            button("+").on_press(Message::Increment),
 
             // We show the value of the counter here
             text(self.value).size(50),
 
             // The decrement button. We tell it to produce a
-            // `DecrementPressed` message when pressed
-            button("-").on_press(Message::DecrementPressed),
+            // `Decrement` message when pressed
+            button("-").on_press(Message::Decrement),
         ]
     }
 }
@@ -160,8 +160,15 @@ impl Counter {
 }
 ```
 
-And that's everything! We just wrote a whole user interface. Iced is now able
-to:
+And that's everything! We just wrote a whole user interface. Let's run it:
+
+```rust
+fn main() -> iced::Result {
+    iced::run("A cool counter", Counter::update, Counter::view)
+}
+```
+
+Iced will automatically:
 
   1. Take the result of our __view logic__ and layout its widgets.
   1. Process events from our system and produce __messages__ for our

core/src/angle.rs

@@ -7,6 +7,18 @@ use std::ops::{Add, AddAssign, Div, Mul, RangeInclusive, Sub, SubAssign};
 #[derive(Debug, Copy, Clone, PartialEq, PartialOrd)]
 pub struct Degrees(pub f32);
 
+impl PartialEq<f32> for Degrees {
+    fn eq(&self, other: &f32) -> bool {
+        self.0.eq(other)
+    }
+}
+
+impl PartialOrd<f32> for Degrees {
+    fn partial_cmp(&self, other: &f32) -> Option<std::cmp::Ordering> {
+        self.0.partial_cmp(other)
+    }
+}
+
 /// Radians
 #[derive(Debug, Copy, Clone, PartialEq, PartialOrd)]
 pub struct Radians(pub f32);
@@ -140,3 +152,15 @@ impl Div for Radians {
         Self(self.0 / rhs.0)
     }
 }
+
+impl PartialEq<f32> for Radians {
+    fn eq(&self, other: &f32) -> bool {
+        self.0.eq(other)
+    }
+}
+
+impl PartialOrd<f32> for Radians {
+    fn partial_cmp(&self, other: &f32) -> Option<std::cmp::Ordering> {
+        self.0.partial_cmp(other)
+    }
+}

examples/arc/src/main.rs

@@ -1,20 +1,17 @@
 use std::{f32::consts::PI, time::Instant};
 
-use iced::executor;
 use iced::mouse;
 use iced::widget::canvas::{
     self, stroke, Cache, Canvas, Geometry, Path, Stroke,
 };
-use iced::{
-    Application, Command, Element, Length, Point, Rectangle, Renderer,
-    Settings, Subscription, Theme,
-};
+use iced::{Element, Length, Point, Rectangle, Renderer, Subscription, Theme};
 
 pub fn main() -> iced::Result {
-    Arc::run(Settings {
-        antialiasing: true,
-        ..Settings::default()
-    })
+    iced::sandbox("Arc - Iced", Arc::update, Arc::view)
+        .subscription(Arc::subscription)
+        .theme(|_| Theme::Dark)
+        .antialiased()
+        .run()
 }
 
 struct Arc {
@@ -27,30 +24,9 @@ enum Message {
     Tick,
 }
 
-impl Application for Arc {
-    type Executor = executor::Default;
-    type Message = Message;
-    type Theme = Theme;
-    type Flags = ();
-
-    fn new(_flags: ()) -> (Self, Command<Message>) {
-        (
-            Arc {
-                start: Instant::now(),
-                cache: Cache::default(),
-            },
-            Command::none(),
-        )
-    }
-
-    fn title(&self) -> String {
-        String::from("Arc - Iced")
-    }
-
-    fn update(&mut self, _: Message) -> Command<Message> {
+impl Arc {
+    fn update(&mut self, _: Message) {
         self.cache.clear();
-
-        Command::none()
     }
 
     fn view(&self) -> Element<Message> {
@@ -60,16 +36,21 @@ impl Application for Arc {
             .into()
     }
 
-    fn theme(&self) -> Theme {
-        Theme::Dark
-    }
-
     fn subscription(&self) -> Subscription<Message> {
         iced::time::every(std::time::Duration::from_millis(10))
             .map(|_| Message::Tick)
     }
 }
 
+impl Default for Arc {
+    fn default() -> Self {
+        Arc {
+            start: Instant::now(),
+            cache: Cache::default(),
+        }
+    }
+}
+
 impl<Message> canvas::Program<Message> for Arc {
     type State = ();
 

examples/bezier_tool/src/main.rs

@@ -1,12 +1,11 @@
 //! This example showcases an interactive `Canvas` for drawing Bézier curves.
 use iced::widget::{button, column, text};
-use iced::{Alignment, Element, Length, Sandbox, Settings};
+use iced::{Alignment, Element, Length};
 
 pub fn main() -> iced::Result {
-    Example::run(Settings {
-        antialiasing: true,
-        ..Settings::default()
-    })
+    iced::sandbox("Bezier Tool - Iced", Example::update, Example::view)
+        .antialiased()
+        .run()
 }
 
 #[derive(Default)]
@@ -21,17 +20,7 @@ enum Message {
     Clear,
 }
 
-impl Sandbox for Example {
-    type Message = Message;
-
-    fn new() -> Self {
-        Example::default()
-    }
-
-    fn title(&self) -> String {
-        String::from("Bezier tool - Iced")
-    }
-
+impl Example {
     fn update(&mut self, message: Message) {
         match message {
             Message::AddCurve(curve) => {

examples/checkbox/src/main.rs

@@ -1,12 +1,12 @@
-use iced::executor;
-use iced::font::{self, Font};
 use iced::widget::{checkbox, column, container, row, text};
-use iced::{Application, Command, Element, Length, Settings, Theme};
+use iced::{Element, Font, Length};
 
 const ICON_FONT: Font = Font::with_name("icons");
 
 pub fn main() -> iced::Result {
-    Example::run(Settings::default())
+    iced::sandbox("Checkbox - Iced", Example::update, Example::view)
+        .font(include_bytes!("../fonts/icons.ttf").as_slice())
+        .run()
 }
 
 #[derive(Default)]
@@ -21,28 +21,10 @@ enum Message {
     DefaultToggled(bool),
     CustomToggled(bool),
     StyledToggled(bool),
-    FontLoaded(Result<(), font::Error>),
 }
 
-impl Application for Example {
-    type Message = Message;
-    type Flags = ();
-    type Executor = executor::Default;
-    type Theme = Theme;
-
-    fn new(_flags: Self::Flags) -> (Self, Command<Message>) {
-        (
-            Self::default(),
-            font::load(include_bytes!("../fonts/icons.ttf").as_slice())
-                .map(Message::FontLoaded),
-        )
-    }
-
-    fn title(&self) -> String {
-        String::from("Checkbox - Iced")
-    }
-
-    fn update(&mut self, message: Message) -> Command<Message> {
+impl Example {
+    fn update(&mut self, message: Message) {
         match message {
             Message::DefaultToggled(default) => {
                 self.default = default;
@@ -53,10 +35,7 @@ impl Application for Example {
             Message::CustomToggled(custom) => {
                 self.custom = custom;
             }
-            Message::FontLoaded(_) => (),
         }
-
-        Command::none()
     }
 
     fn view(&self) -> Element<Message> {