GUI app for chapter2;

rust/Cargo.toml

@@ -1,3 +1,3 @@
 [workspace]
 
-members = ["ast_utils"]
+members = ["ast_utils", "chapter2"]

rust/chapter2/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "chapter2"
+version = "0.1.0"
+authors = ["Timo Sulg <[email protected]>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+orbtk = "0.3.1-alpha1"

rust/chapter2/src/main.rs

@@ -0,0 +1,142 @@
+extern crate orbtk;
+
+use orbtk::prelude::*;
+use std::cell::Cell;
+
+#[derive(Debug, Copy, Clone)]
+enum Action {
+    ClearText,
+    Convert,
+    InputChanged(entity),
+}
+
+#[derive(Default)]
+pub struct MainViewState {
+    action: Cell<Option<Action>>,
+}
+
+impl MainViewState {
+    fn action(&self, action: Action) {
+        self.action.set(Some(action));
+    }
+}
+
+impl State for MainViewState {
+    fn update(&self, ctx: &mut Context<'_>) {
+        if let Some(action) = self.action.get() {
+            match action {
+                Action::ClearText => {
+                    ctx.widget().set("text_input", String16::from(""));
+                    ctx.widget().set("text_result", String16::from(""));
+                }
+                Action::Convert => {
+                    let input = *ctx.widget().get::<f64>("input");
+                    let result_txt = format!("{:.9}", input);
+                    ctx.widget().set("text_result", String16::from(result_txt));
+                }
+                Action::InputChanged(entity) => {
+                    let value = *ctx.get_widget(entity).get::<f64>("text");
+                    *ctx.widget().get_mut::<f64>("input") = value;
+                    println!("entry changed: {}", value);
+                }
+                _ => {
+                    println!("unsupported action");
+                }
+            }
+
+            self.action.set(None);
+        }
+    }
+}
+
+fn create_header(ctx: &mut BuildContext, text: &str) -> Entity {
+    TextBlock::create()
+        .text(text)
+        .selector(Selector::new().with("text-block").class("h1"))
+        .build(ctx)
+}
+
+widget!(
+    MainView<MainViewState> {
+        input: f64,
+        text_input: String16,
+        text_result: String16
+    }
+);
+
+impl Template for MainView {
+    fn template(self, id: Entity, ctx: &mut BuildContext) -> Self {
+        let clear_state = self.clone_state();
+        let convert_state = self.clone_state();
+        let change_state = self.clone_state();
+
+        self.name("Chapter.2 - Unit conversion")
+            .input(0.0)
+            .text_input("0.0")
+            .text_result("Result: 0")
+            .child(
+                Grid::create()
+                    .margin(10.0)
+                    .columns(Columns::create().column(150.0).column(150.0).build())
+                    .child(
+                        Stack::create()
+                            .attach(Grid::column(0))
+                            .child(create_header(ctx, "From unit"))
+                            .child(
+                                TextBox::create()
+                                    .water_mark("From value")
+                                    .text(("text_input", id))
+                                    .on_changed(move |_, entity| {
+                                        change_state.action(Action::InputChanged(entity));
+                                    })
+                                    .build(ctx),
+                            )
+                            .child(
+                                Button::create()
+                                    .text("Clear")
+                                    .on_click(move |_| {
+                                        clear_state.action(Action::ClearText);
+                                        true
+                                    })
+                                    .build(ctx),
+                            )
+                            .build(ctx),
+                    )
+                    .child(
+                        Stack::create()
+                            .attach(Grid::column(1))
+                            .child(create_header(ctx, "To unit"))
+                            .child(
+                                TextBox::create()
+                                    .water_mark("Result")
+                                    .text(("text_result", id))
+                                    .build(ctx),
+                            )
+                            .child(
+                                Button::create()
+                                    .text("Convert")
+                                    .on_click(move |_| {
+                                        convert_state.action(Action::Convert);
+                                        true
+                                    })
+                                    .build(ctx),
+                            )
+                            .build(ctx),
+                    )
+                    .build(ctx),
+            )
+    }
+}
+
+fn main() {
+    Application::new()
+        .window(|ctx| {
+            Window::create()
+                .title("Chapter.2 - unit conversion")
+                .position((100.0, 100.0))
+                .size(450.0, 450.0)
+                .child(MainView::create().build(ctx))
+                .build(ctx)
+        })
+        .run()
+}