Decouple iced from coffee

src/widget/text.rs

@@ -0,0 +1,223 @@
+//! Write some text for your users to read.
+use crate::{
+    Element, Hasher, Layout, MouseCursor, Node, Point, Rectangle, Style, Widget,
+};
+
+use std::hash::Hash;
+
+/// A fragment of text.
+///
+/// It implements [`Widget`] when the associated [`core::Renderer`] implements
+/// the [`text::Renderer`] trait.
+///
+/// [`Widget`]: ../../core/trait.Widget.html
+/// [`core::Renderer`]: ../../core/trait.Renderer.html
+/// [`text::Renderer`]: trait.Renderer.html
+///
+/// # Example
+///
+/// ```
+/// use iced::Text;
+///
+/// Text::<(f32, f32, f32)>::new("I <3 iced!")
+///     .size(40)
+///     .color((0.0, 0.0, 1.0));
+/// ```
+#[derive(Debug, Clone)]
+pub struct Text<Color> {
+    content: String,
+    size: u16,
+    color: Color,
+    style: Style,
+    horizontal_alignment: HorizontalAlignment,
+    vertical_alignment: VerticalAlignment,
+}
+
+impl<Color> Text<Color>
+where
+    Color: Default,
+{
+    /// Create a new fragment of [`Text`] with the given contents.
+    ///
+    /// [`Text`]: struct.Text.html
+    pub fn new(label: &str) -> Self {
+        Text {
+            content: String::from(label),
+            size: 20,
+            color: Color::default(),
+            style: Style::default().fill_width(),
+            horizontal_alignment: HorizontalAlignment::Left,
+            vertical_alignment: VerticalAlignment::Top,
+        }
+    }
+
+    /// Sets the size of the [`Text`] in pixels.
+    ///
+    /// [`Text`]: struct.Text.html
+    pub fn size(mut self, size: u16) -> Self {
+        self.size = size;
+        self
+    }
+
+    /// Sets the [`Color`] of the [`Text`].
+    ///
+    /// [`Text`]: struct.Text.html
+    /// [`Color`]: ../../../graphics/struct.Color.html
+    pub fn color(mut self, color: Color) -> Self {
+        self.color = color;
+        self
+    }
+
+    /// Sets the width of the [`Text`] boundaries in pixels.
+    ///
+    /// [`Text`]: struct.Text.html
+    pub fn width(mut self, width: u32) -> Self {
+        self.style = self.style.width(width);
+        self
+    }
+
+    /// Sets the height of the [`Text`] boundaries in pixels.
+    ///
+    /// [`Text`]: struct.Text.html
+    pub fn height(mut self, height: u32) -> Self {
+        self.style = self.style.height(height);
+        self
+    }
+
+    /// Sets the [`HorizontalAlignment`] of the [`Text`].
+    ///
+    /// [`Text`]: struct.Text.html
+    /// [`HorizontalAlignment`]: ../../../graphics/enum.HorizontalAlignment.html
+    pub fn horizontal_alignment(
+        mut self,
+        alignment: HorizontalAlignment,
+    ) -> Self {
+        self.horizontal_alignment = alignment;
+        self
+    }
+
+    /// Sets the [`VerticalAlignment`] of the [`Text`].
+    ///
+    /// [`Text`]: struct.Text.html
+    /// [`VerticalAlignment`]: ../../../graphics/enum.VerticalAlignment.html
+    pub fn vertical_alignment(mut self, alignment: VerticalAlignment) -> Self {
+        self.vertical_alignment = alignment;
+        self
+    }
+}
+
+impl<Message, Renderer, Color> Widget<Message, Renderer> for Text<Color>
+where
+    Color: Copy + std::fmt::Debug,
+    Renderer: self::Renderer<Color>,
+{
+    fn node(&self, renderer: &Renderer) -> Node {
+        renderer.node(self.style, &self.content, self.size as f32)
+    }
+
+    fn draw(
+        &self,
+        renderer: &mut Renderer,
+        layout: Layout<'_>,
+        _cursor_position: Point,
+    ) -> MouseCursor {
+        renderer.draw(
+            layout.bounds(),
+            &self.content,
+            self.size as f32,
+            self.color,
+            self.horizontal_alignment,
+            self.vertical_alignment,
+        );
+
+        MouseCursor::OutOfBounds
+    }
+
+    fn hash(&self, state: &mut Hasher) {
+        self.style.hash(state);
+
+        self.content.hash(state);
+        self.size.hash(state);
+    }
+}
+
+/// The renderer of a [`Text`] fragment.
+///
+/// Your [`core::Renderer`] will need to implement this trait before being
+/// able to use a [`Text`] in your user interface.
+///
+/// [`Text`]: struct.Text.html
+/// [`core::Renderer`]: ../../core/trait.Renderer.html
+pub trait Renderer<Color> {
+    /// Creates a [`Node`] with the given [`Style`] for the provided [`Text`]
+    /// contents and size.
+    ///
+    /// You should probably use [`Node::with_measure`] to allow [`Text`] to
+    /// adapt to the dimensions of its container.
+    ///
+    /// [`Node`]: ../../core/struct.Node.html
+    /// [`Style`]: ../../core/struct.Style.html
+    /// [`Text`]: struct.Text.html
+    /// [`Node::with_measure`]: ../../core/struct.Node.html#method.with_measure
+    fn node(&self, style: Style, content: &str, size: f32) -> Node;
+
+    /// Draws a [`Text`] fragment.
+    ///
+    /// It receives:
+    ///   * the bounds of the [`Text`]
+    ///   * the contents of the [`Text`]
+    ///   * the size of the [`Text`]
+    ///   * the color of the [`Text`]
+    ///   * the [`HorizontalAlignment`] of the [`Text`]
+    ///   * the [`VerticalAlignment`] of the [`Text`]
+    ///
+    /// [`Text`]: struct.Text.html
+    /// [`HorizontalAlignment`]: ../../../graphics/enum.HorizontalAlignment.html
+    /// [`VerticalAlignment`]: ../../../graphics/enum.VerticalAlignment.html
+    fn draw(
+        &mut self,
+        bounds: Rectangle<f32>,
+        content: &str,
+        size: f32,
+        color: Color,
+        horizontal_alignment: HorizontalAlignment,
+        vertical_alignment: VerticalAlignment,
+    );
+}
+
+impl<'a, Message, Renderer, Color> From<Text<Color>>
+    for Element<'a, Message, Renderer>
+where
+    Color: 'static + Copy + std::fmt::Debug,
+    Renderer: self::Renderer<Color>,
+{
+    fn from(text: Text<Color>) -> Element<'a, Message, Renderer> {
+        Element::new(text)
+    }
+}
+
+/// The horizontal alignment of some resource.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum HorizontalAlignment {
+    /// Align left
+    Left,
+
+    /// Horizontally centered
+    Center,
+
+    /// Align right
+    Right,
+}
+
+/// The vertical alignment of some resource.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum VerticalAlignment {
+    /// Align top
+    Top,
+
+    /// Vertically centered
+    Center,
+
+    /// Align bottom
+    Bottom,
+}