Implement Widget::draw for Text

native/src/renderer.rs

@@ -19,13 +19,17 @@
 //! [`text::Renderer`]: crate::widget::text::Renderer
 //! [`Checkbox`]: crate::widget::Checkbox
 //! [`checkbox::Renderer`]: crate::widget::checkbox::Renderer
+pub mod text;
+
+pub use text::Text;
 
 #[cfg(debug_assertions)]
 mod null;
 #[cfg(debug_assertions)]
 pub use null::Null;
 
-use crate::{layout, Element, Rectangle};
+use crate::layout;
+use crate::{Element, Rectangle};
 
 /// A component that can take the state of a user interface and produce an
 /// output for its users.
@@ -48,4 +52,6 @@ pub trait Renderer: Sized {
     }
 
     fn with_layer(&mut self, bounds: Rectangle, f: impl FnOnce(&mut Self));
+
+    fn clear(&mut self);
 }

native/src/renderer/null.rs

@@ -4,12 +4,13 @@ use crate::container;
 use crate::pane_grid;
 use crate::progress_bar;
 use crate::radio;
+use crate::renderer::{self, Renderer};
 use crate::scrollable;
 use crate::slider;
 use crate::text;
 use crate::text_input;
 use crate::toggler;
-use crate::{Font, Padding, Point, Rectangle, Renderer, Size};
+use crate::{Font, Padding, Point, Rectangle, Size};
 
 /// A renderer that does nothing.
 ///
@@ -28,11 +29,17 @@ impl Renderer for Null {
     type Defaults = ();
 
     fn with_layer(&mut self, _bounds: Rectangle, _f: impl FnOnce(&mut Self)) {}
+
+    fn clear(&mut self) {}
+}
+
+impl renderer::Text for Null {
+    type Font = Font;
+
+    fn fill_text(&mut self, _text: renderer::text::Section<'_, Self::Font>) {}
 }
 
 impl text::Renderer for Null {
-    type Font = Font;
-
     fn default_size(&self) -> u16 {
         20
     }

native/src/renderer/text.rs

@@ -0,0 +1,20 @@
+use crate::alignment;
+use crate::{Color, Rectangle, Renderer};
+
+pub trait Text: Renderer {
+    /// The font type used.
+    type Font: Default + Copy;
+
+    fn fill_text(&mut self, section: Section<'_, Self::Font>);
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct Section<'a, Font> {
+    pub content: &'a str,
+    pub bounds: Rectangle,
+    pub size: Option<f32>,
+    pub color: Option<Color>,
+    pub font: Font,
+    pub horizontal_alignment: alignment::Horizontal,
+    pub vertical_alignment: alignment::Vertical,
+}

native/src/user_interface.rs

@@ -330,6 +330,9 @@ where
     /// }
     /// ```
     pub fn draw(&mut self, renderer: &mut Renderer, cursor_position: Point) {
+        // TODO: Move to shell level (?)
+        renderer.clear();
+
         let viewport = Rectangle::with_size(self.bounds);
 
         let overlay = if let Some(mut overlay) =

native/src/widget/text.rs

@@ -1,6 +1,7 @@
 //! Write some text for your users to read.
 use crate::alignment;
 use crate::layout;
+use crate::renderer;
 use crate::{
     Color, Element, Hasher, Layout, Length, Point, Rectangle, Size, Widget,
 };
@@ -133,13 +134,35 @@ where
 
     fn draw(
         &self,
-        _renderer: &mut Renderer,
+        renderer: &mut Renderer,
         _defaults: &Renderer::Defaults,
-        _layout: Layout<'_>,
+        layout: Layout<'_>,
         _cursor_position: Point,
         _viewport: &Rectangle,
     ) {
-        // TODO
+        let bounds = layout.bounds();
+
+        let x = match self.horizontal_alignment {
+            alignment::Horizontal::Left => bounds.x,
+            alignment::Horizontal::Center => bounds.center_x(),
+            alignment::Horizontal::Right => bounds.x + bounds.width,
+        };
+
+        let y = match self.vertical_alignment {
+            alignment::Vertical::Top => bounds.y,
+            alignment::Vertical::Center => bounds.center_y(),
+            alignment::Vertical::Bottom => bounds.y + bounds.height,
+        };
+
+        renderer.fill_text(renderer::text::Section {
+            content: &self.content,
+            size: self.size.map(f32::from),
+            bounds: Rectangle { x, y, ..bounds },
+            color: self.color,
+            font: self.font,
+            horizontal_alignment: self.horizontal_alignment,
+            vertical_alignment: self.vertical_alignment,
+        });
     }
 
     fn hash_layout(&self, state: &mut Hasher) {
@@ -159,10 +182,7 @@ where
 /// able to use [`Text`] in your user interface.
 ///
 /// [renderer]: crate::Renderer
-pub trait Renderer: crate::Renderer {
-    /// The font type used for [`Text`].
-    type Font: Default + Copy;
-
+pub trait Renderer: renderer::Text {
     /// Returns the default size of [`Text`].
     fn default_size(&self) -> u16;