Make tour work with iced_web again 🎉

- Implements `TextInput`, `Scrollable`, and `Container`
- Adds basic style generation

web/src/widget/container.rs

@@ -0,0 +1,142 @@
+use crate::{bumpalo, style, Align, Bus, Element, Length, Style, Widget};
+
+/// An element decorating some content.
+///
+/// It is normally used for alignment purposes.
+#[allow(missing_debug_implementations)]
+pub struct Container<'a, Message> {
+    width: Length,
+    height: Length,
+    max_width: u32,
+    max_height: u32,
+    horizontal_alignment: Align,
+    vertical_alignment: Align,
+    content: Element<'a, Message>,
+}
+
+impl<'a, Message> Container<'a, Message> {
+    /// Creates an empty [`Container`].
+    ///
+    /// [`Container`]: struct.Container.html
+    pub fn new<T>(content: T) -> Self
+    where
+        T: Into<Element<'a, Message>>,
+    {
+        use std::u32;
+
+        Container {
+            width: Length::Shrink,
+            height: Length::Shrink,
+            max_width: u32::MAX,
+            max_height: u32::MAX,
+            horizontal_alignment: Align::Start,
+            vertical_alignment: Align::Start,
+            content: content.into(),
+        }
+    }
+
+    /// Sets the width of the [`Container`].
+    ///
+    /// [`Container`]: struct.Container.html
+    pub fn width(mut self, width: Length) -> Self {
+        self.width = width;
+        self
+    }
+
+    /// Sets the height of the [`Container`].
+    ///
+    /// [`Container`]: struct.Container.html
+    pub fn height(mut self, height: Length) -> Self {
+        self.height = height;
+        self
+    }
+
+    /// Sets the maximum width of the [`Container`].
+    ///
+    /// [`Container`]: struct.Container.html
+    pub fn max_width(mut self, max_width: u32) -> Self {
+        self.max_width = max_width;
+        self
+    }
+
+    /// Sets the maximum height of the [`Container`] in pixels.
+    ///
+    /// [`Container`]: struct.Container.html
+    pub fn max_height(mut self, max_height: u32) -> Self {
+        self.max_height = max_height;
+        self
+    }
+
+    /// Centers the contents in the horizontal axis of the [`Container`].
+    ///
+    /// [`Container`]: struct.Container.html
+    pub fn center_x(mut self) -> Self {
+        self.horizontal_alignment = Align::Center;
+
+        self
+    }
+
+    /// Centers the contents in the vertical axis of the [`Container`].
+    ///
+    /// [`Container`]: struct.Container.html
+    pub fn center_y(mut self) -> Self {
+        self.vertical_alignment = Align::Center;
+
+        self
+    }
+}
+
+impl<'a, Message> Widget<Message> for Container<'a, Message>
+where
+    Message: 'static,
+{
+    fn node<'b>(
+        &self,
+        bump: &'b bumpalo::Bump,
+        bus: &Bus<Message>,
+        style_sheet: &mut style::Sheet<'b>,
+    ) -> dodrio::Node<'b> {
+        use dodrio::builder::*;
+
+        let column_class = style_sheet.insert(bump, Style::Column);
+
+        let width = style::length(self.width);
+        let height = style::length(self.height);
+
+        let align_items = style::align(self.horizontal_alignment);
+        let justify_content = style::align(self.vertical_alignment);
+
+        let node = div(bump)
+            .attr(
+                "class",
+                bumpalo::format!(in bump, "{}", column_class).into_bump_str(),
+            )
+            .attr(
+                "style",
+                bumpalo::format!(
+                    in bump,
+                    "width: {}; height: {}; max-width: {}px; align-items: {}; justify-content: {}",
+                    width,
+                    height,
+                    self.max_width,
+                    align_items,
+                    justify_content
+                )
+                .into_bump_str(),
+            )
+            .children(vec![self.content.node(bump, bus, style_sheet)]);
+
+        // TODO: Complete styling
+
+        node.finish()
+    }
+}
+
+impl<'a, Message> From<Container<'a, Message>> for Element<'a, Message>
+where
+    Message: 'static + Clone,
+{
+    fn from(container: Container<'a, Message>) -> Element<'a, Message> {
+        Element::new(container)
+    }
+}