Keep process contribution editors fully visible in compact windows

crates/oa-desktop/src/behavior/topology/view.rs

@@ -305,6 +305,7 @@ pub(super) fn view<'a>(
             button("Back to caller").on_press(Message::TopologyCanvas(CanvasEvent::Back(context))),
         );
     }
+    let mut form_panel: Element<'_, Message> = iced::widget::Space::new().height(0).into();
     if let Some(d) = state.draft.as_ref().filter(|d| d.owner == owner) {
         let mut form = column![text(d.tool.title()).size(16)].spacing(8);
         if let Some(link) = d.insertion.link.and_then(|id| p.relations.get(&id)) {
@@ -473,21 +474,65 @@ pub(super) fn view<'a>(
             button("Cancel").on_press(event(Event::Cancel))
         ]
         .spacing(7);
-        out = out.push(
-            container(
-                column![
-                    actions,
-                    scrollable(form).height((app.window_size.height - 520.).clamp(150., 260.))
-                ]
-                .spacing(8),
-            )
-            .padding(12)
-            .style(style::card),
-        );
+        form_panel = editor_panel(actions.into(), form.into());
     }
-    super::super::scenario_scroll::observe_topology(
-        context,
-        scenario::ScrollArea::Page,
-        scrollable(out.padding(18)),
+    panes(
+        super::super::scenario_scroll::observe_topology(
+            context,
+            scenario::ScrollArea::Page,
+            scrollable(out.padding(18)),
+        ),
+        form_panel,
+        pending,
     )
 }
+
+/// Keep the diagram mounted while an independent editor uses the remaining
+/// workspace height. The editor must never be clipped by the page scrollable.
+fn panes<'a, R: iced::advanced::Renderer + 'a>(
+    diagram: iced::Element<'a, Message, iced::Theme, R>,
+    form: iced::Element<'a, Message, iced::Theme, R>,
+    pending: bool,
+) -> iced::Element<'a, Message, iced::Theme, R> {
+    column![
+        container(diagram).width(Fill).height(if pending {
+            iced::Length::FillPortion(1)
+        } else {
+            Fill
+        }),
+        container(form).width(Fill).height(if pending {
+            iced::Length::FillPortion(1)
+        } else {
+            iced::Length::Shrink
+        }),
+    ]
+    .width(Fill)
+    .height(Fill)
+    .into()
+}
+
+fn editor_panel<'a, R: iced::advanced::text::Renderer + 'a>(
+    actions: iced::Element<'a, Message, iced::Theme, R>,
+    fields: iced::Element<'a, Message, iced::Theme, R>,
+) -> iced::Element<'a, Message, iced::Theme, R> {
+    container(
+        container(column![actions, scrollable(fields).id("process-form").height(Fill)].spacing(8))
+            .width(Fill)
+            .height(Fill)
+            .padding(12)
+            .style(style::card),
+    )
+    .width(Fill)
+    .height(Fill)
+    .padding(iced::Padding {
+        top: 0.,
+        right: 18.,
+        bottom: 18.,
+        left: 18.,
+    })
+    .into()
+}
+
+#[cfg(all(test, debug_assertions))]
+#[path = "layout_tests.rs"]
+mod layout_tests;