app work

src/core/position/span.rs

@@ -3,6 +3,7 @@ use crate::prelude::*;
 pub struct Span {
     pub children: Vec<(WidgetId, SpanLen)>,
     pub dir: Dir,
+    pub spacing: f32,
 }
 
 impl Widget for Span {
@@ -36,6 +37,7 @@ impl Widget for Span {
                 child_region.flip(self.dir.axis);
             }
             painter.widget_within(child, child_region);
+            start.abs += self.spacing;
         }
     }
 
@@ -45,7 +47,10 @@ impl Widget for Span {
         let dir_len = if total.ratio != 0.0 {
             UiScalar::rel_max()
         } else {
-            UiScalar::new(total.rel, total.abs)
+            UiScalar::new(
+                total.rel,
+                total.abs + self.spacing * self.children.len().saturating_sub(1) as f32,
+            )
         };
         let mut max_ortho = UiScalar::ZERO;
         for (child, _) in &self.children {
@@ -68,9 +73,15 @@ impl Span {
         Self {
             children: Vec::new(),
             dir,
+            spacing: 0.0,
         }
     }
 
+    pub fn spacing(mut self, spacing: impl UiNum) -> Self {
+        self.spacing = spacing.to_f32();
+        self
+    }
+
     fn setup(&mut self, ctx: &mut SizeCtx) -> SpanLenSums {
         self.children
             .iter_mut()