Add kas::theme::SelectionStyle

crates/kas-core/src/theme/draw.rs

@@ -5,7 +5,7 @@
 
 //! "Handle" types used by themes
 
-use super::{FrameStyle, MarkStyle, SizeMgr, TextClass, ThemeSize};
+use super::{FrameStyle, MarkStyle, SelectionStyle, SizeMgr, TextClass, ThemeSize};
 use crate::dir::Direction;
 use crate::draw::color::Rgb;
 use crate::draw::{Draw, DrawIface, DrawShared, DrawSharedImpl, ImageId, PassType};
@@ -194,13 +194,13 @@ impl<'a> DrawMgr<'a> {
         self.h.separator(rect);
     }
 
-    /// Draw a selection box
+    /// Draw a selection highlight / frame
     ///
-    /// This appears as a dashed box or similar around this `rect`. Note that
-    /// the selection indicator is drawn *outside* of this rect, within a margin
-    /// of size [`SizeMgr::inner_margins`] that is expected to be present around this box.
-    pub fn selection_box(&mut self, rect: Rect) {
-        self.h.selection_box(rect);
+    /// Adjusts the background color and/or draws a line around the given rect.
+    /// In the latter case, a margin of size [`SizeMgr::inner_margins`] around
+    /// `rect` is expected.
+    pub fn selection(&mut self, rect: Rect, style: SelectionStyle) {
+        self.h.selection(rect, style);
     }
 
     /// Draw text
@@ -412,12 +412,8 @@ pub trait ThemeDraw {
     /// Draw a separator in the given `rect`
     fn separator(&mut self, rect: Rect);
 
-    /// Draw a selection box
-    ///
-    /// This appears as a dashed box or similar around this `rect`. Note that
-    /// the selection indicator is drawn *outside* of this rect, within a margin
-    /// of size `inner_margin` that is expected to be present around this box.
-    fn selection_box(&mut self, rect: Rect);
+    /// Draw a selection highlight / frame
+    fn selection(&mut self, rect: Rect, style: SelectionStyle);
 
     /// Draw text
     ///

crates/kas-core/src/theme/simple_theme.rs

@@ -20,7 +20,7 @@ use kas::text::{fonts, Effect, TextApi, TextDisplay};
 use kas::theme::dimensions as dim;
 use kas::theme::{Background, FrameStyle, MarkStyle, TextClass};
 use kas::theme::{ColorsLinear, Config, InputState, Theme};
-use kas::theme::{ThemeControl, ThemeDraw, ThemeSize};
+use kas::theme::{SelectionStyle, ThemeControl, ThemeDraw, ThemeSize};
 use kas::{Action, WidgetId};
 
 /// A simple theme
@@ -362,12 +362,24 @@ where
         self.draw.rect(outer, self.cols.frame);
     }
 
-    fn selection_box(&mut self, rect: Rect) {
+    fn selection(&mut self, rect: Rect, style: SelectionStyle) {
         let inner = Quad::conv(rect);
-        let outer = inner.grow(self.w.dims.m_inner.into());
-        // TODO: this should use its own colour and a stippled pattern
-        let col = self.cols.text_sel_bg;
-        self.draw.frame(outer, inner, col);
+        match style {
+            SelectionStyle::Highlight => {
+                self.draw.rect(inner, self.cols.text_sel_bg);
+            }
+            SelectionStyle::Frame => {
+                let outer = inner.grow(self.w.dims.m_inner.into());
+                // TODO: this should use its own colour and a stippled pattern
+                let col = self.cols.accent;
+                self.draw.frame(outer, inner, col);
+            }
+            SelectionStyle::Both => {
+                let outer = inner.grow(self.w.dims.m_inner.into());
+                self.draw.rect(outer, self.cols.accent);
+                self.draw.rect(inner, self.cols.text_sel_bg);
+            }
+        }
     }
 
     fn text(&mut self, id: &WidgetId, rect: Rect, text: &TextDisplay, _: TextClass) {

crates/kas-core/src/theme/style.rs

@@ -94,6 +94,28 @@ pub enum FrameStyle {
     Window,
 }
 
+/// Selection style hint
+///
+/// How to draw selections
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Ord, PartialOrd, Hash)]
+pub enum SelectionStyle {
+    /// Adjust background color
+    Highlight,
+    /// Draw a frame around the selection
+    Frame,
+    /// Both
+    Both,
+}
+
+impl SelectionStyle {
+    /// True if an external margin is required
+    ///
+    /// Margin size: [`SizeMgr::inner_margins`]
+    pub fn is_external(self) -> bool {
+        matches!(self, SelectionStyle::Frame | SelectionStyle::Both)
+    }
+}
+
 /// Class of text drawn
 ///
 /// Themes choose font, font size, colour, and alignment based on this.

crates/kas-macros/src/extends.rs

@@ -64,16 +64,16 @@ impl Extends {
                 (#base).get_clip_rect()
             }
 
-            fn frame(&mut self, id: &WidgetId, rect: Rect, style: FrameStyle, bg: Background) {
+            fn frame(&mut self, id: &WidgetId, rect: Rect, style: ::kas::theme::FrameStyle, bg: Background) {
                 (#base).frame(id, rect, style, bg);
             }
 
             fn separator(&mut self, rect: Rect) {
                 (#base).separator(rect);
             }
 
-            fn selection_box(&mut self, rect: Rect) {
-                (#base).selection_box(rect);
+            fn selection(&mut self, rect: Rect, style: ::kas::theme::SelectionStyle) {
+                (#base).selection(rect, style);
             }
 
             fn text(&mut self, id: &WidgetId, rect: Rect, text: &TextDisplay, class: TextClass) {

crates/kas-view/src/list_view.rs

@@ -12,6 +12,7 @@ use kas::layout::{solve_size_rules, AlignHints};
 #[allow(unused)] use kas::model::SharedData;
 use kas::model::{ListData, SharedDataMut};
 use kas::prelude::*;
+use kas::theme::SelectionStyle;
 #[allow(unused)] // doc links
 use kas_widgets::ScrollBars;
 use kas_widgets::SelectMsg;
@@ -72,6 +73,7 @@ impl_scope! {
         child_size: Size,
         scroll: ScrollComponent,
         sel_mode: SelectionMode,
+        sel_style: SelectionStyle,
         // TODO(opt): replace selection list with RangeOrSet type?
         selection: LinearSet<T::Key>,
         press_target: Option<(usize, T::Key)>,
@@ -139,6 +141,7 @@ impl_scope! {
                 child_size: Size::ZERO,
                 scroll: Default::default(),
                 sel_mode: SelectionMode::None,
+                sel_style: SelectionStyle::Highlight,
                 selection: Default::default(),
                 press_target: None,
             }
@@ -236,6 +239,32 @@ impl_scope! {
             self
         }
 
+        /// Get the current selection style
+        pub fn selection_style(&self) -> SelectionStyle {
+            self.sel_style
+        }
+        /// Set the current selection style
+        ///
+        /// By default, [`SelectionStyle::Highlight`] is used. Other modes may
+        /// add margin between elements.
+        pub fn set_selection_style(&mut self, style: SelectionStyle) -> Action {
+            let action = if style.is_external() != self.sel_style.is_external() {
+                Action::RESIZE
+            } else {
+                Action::empty()
+            };
+            self.sel_style = style;
+            action
+        }
+        /// Set the selection style (inline)
+        ///
+        /// See [`Self::set_selection_style`] documentation.
+        #[must_use]
+        pub fn with_selection_style(mut self, style: SelectionStyle) -> Self {
+            self.sel_style = style;
+            self
+        }
+
         /// Read the list of selected entries
         ///
         /// With mode [`SelectionMode::Single`] this may contain zero or one entry;
@@ -473,7 +502,11 @@ impl_scope! {
     impl Layout for Self {
         fn size_rules(&mut self, size_mgr: SizeMgr, mut axis: AxisInfo) -> SizeRules {
             // We use an invisible frame for highlighting selections, drawing into the margin
-            let inner_margin = size_mgr.inner_margins().extract(axis);
+            let inner_margin = if self.sel_style.is_external() {
+                size_mgr.inner_margins().extract(axis)
+            } else {
+                (0, 0)
+            };
             let frame = kas::layout::FrameRules::new(0, inner_margin, (0, 0));
 
             let other = axis.other().map(|mut size| {
@@ -579,12 +612,12 @@ impl_scope! {
             let offset = self.scroll_offset();
             draw.with_clip_region(self.core.rect, offset, |mut draw| {
                 for child in &mut self.widgets[..self.cur_len.cast()] {
-                    draw.recurse(&mut child.widget);
                     if let Some(ref key) = child.key {
                         if self.selection.contains(key) {
-                            draw.selection_box(child.widget.rect());
+                            draw.selection(child.widget.rect(), self.sel_style);
                         }
                     }
+                    draw.recurse(&mut child.widget);
                 }
             });
         }

crates/kas-view/src/matrix_view.rs

@@ -12,6 +12,7 @@ use kas::layout::{solve_size_rules, AlignHints};
 #[allow(unused)] use kas::model::SharedData;
 use kas::model::{MatrixData, SharedDataMut};
 use kas::prelude::*;
+use kas::theme::SelectionStyle;
 #[allow(unused)] // doc links
 use kas_widgets::ScrollBars;
 use kas_widgets::SelectMsg;
@@ -78,6 +79,7 @@ impl_scope! {
         child_size: Size,
         scroll: ScrollComponent,
         sel_mode: SelectionMode,
+        sel_style: SelectionStyle,
         // TODO(opt): replace selection list with RangeOrSet type?
         selection: LinearSet<T::Key>,
         press_target: Option<(usize, T::Key)>,
@@ -115,6 +117,7 @@ impl_scope! {
                 child_size: Size::ZERO,
                 scroll: Default::default(),
                 sel_mode: SelectionMode::None,
+                sel_style: SelectionStyle::Highlight,
                 selection: Default::default(),
                 press_target: None,
             }
@@ -212,6 +215,32 @@ impl_scope! {
             self
         }
 
+        /// Get the current selection style
+        pub fn selection_style(&self) -> SelectionStyle {
+            self.sel_style
+        }
+        /// Set the current selection style
+        ///
+        /// By default, [`SelectionStyle::Highlight`] is used. Other modes may
+        /// add margin between elements.
+        pub fn set_selection_style(&mut self, style: SelectionStyle) -> Action {
+            let action = if style.is_external() != self.sel_style.is_external() {
+                Action::RESIZE
+            } else {
+                Action::empty()
+            };
+            self.sel_style = style;
+            action
+        }
+        /// Set the selection style (inline)
+        ///
+        /// See [`Self::set_selection_style`] documentation.
+        #[must_use]
+        pub fn with_selection_style(mut self, style: SelectionStyle) -> Self {
+            self.sel_style = style;
+            self
+        }
+
         /// Read the list of selected entries
         ///
         /// With mode [`SelectionMode::Single`] this may contain zero or one entry;
@@ -451,7 +480,11 @@ impl_scope! {
     impl Layout for Self {
         fn size_rules(&mut self, size_mgr: SizeMgr, mut axis: AxisInfo) -> SizeRules {
             // We use an invisible frame for highlighting selections, drawing into the margin
-            let inner_margin = size_mgr.inner_margins().extract(axis);
+            let inner_margin = if self.sel_style.is_external() {
+                size_mgr.inner_margins().extract(axis)
+            } else {
+                (0, 0)
+            };
             let frame = kas::layout::FrameRules::new(0, inner_margin, (0, 0));
 
             let other = axis.other().map(|mut size| {
@@ -569,10 +602,10 @@ impl_scope! {
                     // visible, so check intersection before drawing:
                     if rect.intersection(&child.widget.rect()).is_some() {
                         if let Some(ref key) = child.key {
-                            draw.recurse(&mut child.widget);
                             if self.selection.contains(key) {
-                                draw.selection_box(child.widget.rect());
+                                draw.selection(child.widget.rect(), self.sel_style);
                             }
+                            draw.recurse(&mut child.widget);
                         }
                     }
                 }