Draft drawing logic for `Content` and `TitleBar`

3 files changed, 205 insertions, 27 deletions

diff --git a/native/src/widget/pane_grid.rs b/native/src/widget/pane_grid.rs
index 4c037ee9..bf9c76fd 100644
--- a/native/src/widget/pane_grid.rs
+++ b/native/src/widget/pane_grid.rs
@@ -29,8 +29,8 @@ pub use state::{Focus, State};
 pub use title_bar::TitleBar;
 
 use crate::{
-    keyboard, layout, mouse, Clipboard, Element, Event, Hasher, Layout, Length,
-    Point, Size, Widget,
+    container, keyboard, layout, mouse, row, Clipboard, Element, Event, Hasher,
+    Layout, Length, Point, Size, Widget,
 };
 
 /// A collection of panes distributed using either vertical or horizontal splits
@@ -86,7 +86,7 @@ use crate::{
 /// [`PaneGrid`]: struct.PaneGrid.html
 /// [`State`]: struct.State.html
 #[allow(missing_debug_implementations)]
-pub struct PaneGrid<'a, Message, Renderer> {
+pub struct PaneGrid<'a, Message, Renderer: container::Renderer> {
     state: &'a mut state::Internal,
     pressed_modifiers: &'a mut keyboard::ModifiersState,
     elements: Vec<(Pane, Content<'a, Message, Renderer>)>,
@@ -99,7 +99,10 @@ pub struct PaneGrid<'a, Message, Renderer> {
     on_key_press: Option<Box<dyn Fn(KeyPressEvent) -> Option<Message> + 'a>>,
 }
 
-impl<'a, Message, Renderer> PaneGrid<'a, Message, Renderer> {
+impl<'a, Message, Renderer> PaneGrid<'a, Message, Renderer>
+where
+    Renderer: container::Renderer,
+{
     /// Creates a [`PaneGrid`] with the given [`State`] and view function.
     ///
     /// The view function will be called to display each [`Pane`] present in the
@@ -362,7 +365,7 @@ pub struct KeyPressEvent {
 impl<'a, Message, Renderer> Widget<Message, Renderer>
     for PaneGrid<'a, Message, Renderer>
 where
-    Renderer: self::Renderer,
+    Renderer: self::Renderer + container::Renderer,
 {
     fn width(&self) -> Length {
         self.width
@@ -604,7 +607,8 @@ where
         layout: Layout<'_>,
         cursor_position: Point,
     ) -> Renderer::Output {
-        renderer.draw(
+        self::Renderer::draw(
+            renderer,
             defaults,
             &self.elements,
             self.state.picked_pane(),
@@ -636,7 +640,7 @@ where
 ///
 /// [`PaneGrid`]: struct.PaneGrid.html
 /// [renderer]: ../../renderer/index.html
-pub trait Renderer: crate::Renderer + Sized {
+pub trait Renderer: crate::Renderer + container::Renderer + Sized {
     /// Draws a [`PaneGrid`].
     ///
     /// It receives:
@@ -672,9 +676,17 @@ pub trait Renderer: crate::Renderer + Sized {
     fn draw_pane<Message>(
         &mut self,
         defaults: &Self::Defaults,
-        title_bar: Option<&TitleBar<'_, Message, Self>>,
-        body: &Element<'_, Message, Self>,
-        layout: Layout<'_>,
+        title_bar: Option<(&TitleBar<'_, Message, Self>, Layout<'_>)>,
+        body: (&Element<'_, Message, Self>, Layout<'_>),
+        cursor_position: Point,
+    ) -> Self::Output;
+
+    fn draw_title_bar<Message>(
+        &mut self,
+        defaults: &Self::Defaults,
+        style: &Self::Style,
+        title: (&Element<'_, Message, Self>, Layout<'_>),
+        controls: Option<(&Element<'_, Message, Self>, Layout<'_>)>,
         cursor_position: Point,
     ) -> Self::Output;
 }
@@ -682,7 +694,7 @@ pub trait Renderer: crate::Renderer + Sized {
 impl<'a, Message, Renderer> From<PaneGrid<'a, Message, Renderer>>
     for Element<'a, Message, Renderer>
 where
-    Renderer: 'a + self::Renderer,
+    Renderer: 'a + self::Renderer + row::Renderer,
     Message: 'a,
 {
     fn from(
diff --git a/native/src/widget/pane_grid/content.rs b/native/src/widget/pane_grid/content.rs
index e1374c82..a30b0e7d 100644
--- a/native/src/widget/pane_grid/content.rs
+++ b/native/src/widget/pane_grid/content.rs
@@ -1,16 +1,20 @@
+use crate::container;
 use crate::layout;
 use crate::pane_grid::{self, TitleBar};
-use crate::{Clipboard, Element, Event, Hasher, Layout, Point};
+use crate::{Clipboard, Element, Event, Hasher, Layout, Point, Size};
 
 /// The content of a [`Pane`].
 ///
 /// [`Pane`]: struct.Pane.html
-pub struct Content<'a, Message, Renderer> {
+pub struct Content<'a, Message, Renderer: container::Renderer> {
     title_bar: Option<TitleBar<'a, Message, Renderer>>,
     body: Element<'a, Message, Renderer>,
 }
 
-impl<'a, Message, Renderer> Content<'a, Message, Renderer> {
+impl<'a, Message, Renderer> Content<'a, Message, Renderer>
+where
+    Renderer: container::Renderer,
+{
     pub fn new(body: impl Into<Element<'a, Message, Renderer>>) -> Self {
         Self {
             title_bar: None,
@@ -29,7 +33,7 @@ impl<'a, Message, Renderer> Content<'a, Message, Renderer> {
 
 impl<'a, Message, Renderer> Content<'a, Message, Renderer>
 where
-    Renderer: pane_grid::Renderer,
+    Renderer: pane_grid::Renderer + container::Renderer,
 {
     pub fn draw(
         &self,
@@ -38,13 +42,25 @@ where
         layout: Layout<'_>,
         cursor_position: Point,
     ) -> Renderer::Output {
-        renderer.draw_pane(
-            defaults,
-            self.title_bar.as_ref(),
-            &self.body,
-            layout,
-            cursor_position,
-        )
+        if let Some(title_bar) = &self.title_bar {
+            let mut children = layout.children();
+            let title_bar_layout = children.next().unwrap();
+            let body_layout = children.next().unwrap();
+
+            renderer.draw_pane(
+                defaults,
+                Some((title_bar, title_bar_layout)),
+                (&self.body, body_layout),
+                cursor_position,
+            )
+        } else {
+            renderer.draw_pane(
+                defaults,
+                None,
+                (&self.body, layout),
+                cursor_position,
+            )
+        }
     }
 
     pub(crate) fn is_over_drag_target(
@@ -60,7 +76,34 @@ where
         renderer: &Renderer,
         limits: &layout::Limits,
     ) -> layout::Node {
-        self.body.layout(renderer, limits)
+        if let Some(title_bar) = &self.title_bar {
+            let max_size = limits.max();
+
+            let title_bar_layout = title_bar
+                .layout(renderer, &layout::Limits::new(Size::ZERO, max_size));
+
+            let title_bar_size = title_bar_layout.size();
+
+            let mut body_layout = self.body.layout(
+                renderer,
+                &layout::Limits::new(
+                    Size::ZERO,
+                    Size::new(
+                        max_size.width,
+                        max_size.height - title_bar_size.height,
+                    ),
+                ),
+            );
+
+            body_layout.move_to(Point::new(0.0, title_bar_size.height));
+
+            layout::Node::with_children(
+                max_size,
+                vec![title_bar_layout, body_layout],
+            )
+        } else {
+            self.body.layout(renderer, limits)
+        }
     }
 
     pub(crate) fn on_event(
@@ -86,3 +129,13 @@ where
         self.body.hash_layout(state);
     }
 }
+
+impl<'a, T, Message, Renderer> From<T> for Content<'a, Message, Renderer>
+where
+    T: Into<Element<'a, Message, Renderer>>,
+    Renderer: pane_grid::Renderer + container::Renderer,
+{
+    fn from(element: T) -> Self {
+        Self::new(element)
+    }
+}
diff --git a/native/src/widget/pane_grid/title_bar.rs b/native/src/widget/pane_grid/title_bar.rs
index fa868a20..1fd06411 100644
--- a/native/src/widget/pane_grid/title_bar.rs
+++ b/native/src/widget/pane_grid/title_bar.rs
@@ -1,6 +1,119 @@
-use crate::Element;
+use crate::container;
+use crate::layout;
+use crate::pane_grid;
+use crate::{Element, Layout, Point, Size};
 
-pub struct TitleBar<'a, Message, Renderer> {
-    title: String,
-    buttons: Option<Element<'a, Message, Renderer>>,
+pub struct TitleBar<'a, Message, Renderer: container::Renderer> {
+    title: Element<'a, Message, Renderer>,
+    controls: Option<Element<'a, Message, Renderer>>,
+    padding: u16,
+    style: Renderer::Style,
+}
+
+impl<'a, Message, Renderer> TitleBar<'a, Message, Renderer>
+where
+    Renderer: container::Renderer,
+{
+    pub fn new(title: impl Into<Element<'a, Message, Renderer>>) -> Self {
+        Self {
+            title: title.into(),
+            controls: None,
+            padding: 0,
+            style: Renderer::Style::default(),
+        }
+    }
+
+    pub fn controls(
+        mut self,
+        controls: impl Into<Element<'a, Message, Renderer>>,
+    ) -> Self {
+        self.controls = Some(controls.into());
+        self
+    }
+
+    /// Sets the padding of the [`TitleBar`].
+    ///
+    /// [`TitleBar`]: struct.TitleBar.html
+    pub fn padding(mut self, units: u16) -> Self {
+        self.padding = units;
+        self
+    }
+}
+
+impl<'a, Message, Renderer> TitleBar<'a, Message, Renderer>
+where
+    Renderer: pane_grid::Renderer,
+{
+    pub fn draw(
+        &self,
+        renderer: &mut Renderer,
+        defaults: &Renderer::Defaults,
+        layout: Layout<'_>,
+        cursor_position: Point,
+    ) -> Renderer::Output {
+        if let Some(controls) = &self.controls {
+            let mut children = layout.children();
+            let title_layout = children.next().unwrap();
+            let controls_layout = children.next().unwrap();
+
+            renderer.draw_title_bar(
+                defaults,
+                &self.style,
+                (&self.title, title_layout),
+                Some((controls, controls_layout)),
+                cursor_position,
+            )
+        } else {
+            renderer.draw_title_bar(
+                defaults,
+                &self.style,
+                (&self.title, layout),
+                None,
+                cursor_position,
+            )
+        }
+    }
+
+    pub(crate) fn layout(
+        &self,
+        renderer: &Renderer,
+        limits: &layout::Limits,
+    ) -> layout::Node {
+        let padding = f32::from(self.padding);
+        let limits = limits.pad(padding);
+
+        let mut node = if let Some(controls) = &self.controls {
+            let max_size = limits.max();
+
+            let title_layout = self
+                .title
+                .layout(renderer, &layout::Limits::new(Size::ZERO, max_size));
+
+            let title_size = title_layout.size();
+
+            let mut controls_layout = controls.layout(
+                renderer,
+                &layout::Limits::new(
+                    Size::ZERO,
+                    Size::new(
+                        max_size.width - title_size.width,
+                        max_size.height,
+                    ),
+                ),
+            );
+
+            controls_layout.move_to(Point::new(title_size.width, 0.0));
+
+            layout::Node::with_children(
+                max_size,
+                vec![title_layout, controls_layout],
+            )
+        } else {
+            self.title.layout(renderer, &limits)
+        };
+
+        node.move_to(Point::new(padding, padding));
+
+        node
+    }
 }