List selection visible on every backend; win32 layout propagates up, canvases grow, pickers report their selection

CHANGELOG.md

@@ -9,6 +9,39 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+- **win32: a canvas grows with its window, and `on_resize` fires.**
+  `canvas_create`'s width and height are the canvas's natural size on
+  every backend (GTK4 expands the drawing area past its content size,
+  AppKit holds the size at priority 150); win32 stored them as the pin
+  `width()`/`height()`/`canvas_size` set, so a canvas created 80x80 stayed
+  80x80 in a 700px window and `canvas_on_resize` never fired
+  (`tests/resizecb_demo` failed on Windows for that reason). The natural
+  size is the measure's answer now; a pin is still a pin.
+- **win32: a picker's text is its selection, and a programmatic selection
+  fires `on_change`.** The driver's `text` for a picker was always empty
+  (a combo box has no window text to cache), so `tests/picker` failed on
+  Windows; the selected item is cached after every change. `CB_SETCURSEL`
+  sends no `CBN_SELCHANGE`, so `picker_set_selected` invokes the closure
+  itself when the index changed, as GTK4, AppKit and UIKit do.
+- **A selected list row is visible on every backend.** `.aui-row-selected`
+  was painted by GTK4's stylesheet and, on AppKit, Win32 and UIKit, only
+  reported to the driver: a listbox's selection could be read by a spec
+  and not seen by a user. Each backend now paints its system's selection
+  tint over the row's own ground -- Win32 the accent colour as a tint the
+  labels stay legible on (`w32_selection_ground`, a quarter over white or
+  a good third over the dark ground), AppKit
+  `unemphasizedSelectedContentBackgroundColor`, UIKit
+  `tertiarySystemFillColor` -- and takes it off when the class leaves.
+- **win32 lays the containers above a changed stack out again.** A child
+  added to a nested stack (a listbox's rows go into the `each` container
+  inside the app's column) changes that stack's natural size, and the
+  column has to place what follows it lower; the layout request stopped at
+  the nested stack, the column kept the container at the height it had
+  when empty, and 200 rows were drawn over the buttons under it.
+  `w32_request_layout` now climbs to every container whose size can
+  change, stopping after a scrollview or a stack pinned in height, the
+  bounds `set_hidden`'s synchronous climb already used. rebuild_bench is
+  unchanged (0.88-0.95s on screen, 0.63-0.67s headless).
 - **win32 dark mode: fields and text areas wear a dark edge, the accent
   colour while focused.** The dark theme class darkens an EDIT and what it
   draws inside, but the sunken client edge around it is the system's and

backend/aether_ui_macos.m

@@ -2980,8 +2980,26 @@ static void aeui_apply_state_bg(NSView* v) {
         style = objc_getAssociatedObject(v, "aeui-active-style");
     if (!style && objc_getAssociatedObject(v, "aeui-hovered"))
         style = objc_getAssociatedObject(v, "aeui-hover-style");
+    // A selected list row (.aui-row-selected) paints the system's selection
+    // ground over whatever ground it has, the one the other backends paint
+    // too: the unemphasized one, which keeps the labels' own colours legible
+    // in both appearances (an emphasized selection wants white text, and
+    // the row's labels are the app's).
+    if (!style && objc_getAssociatedObject(v, "aeui-row-selected")) {
+        [v setWantsLayer:YES];
+        v.layer.backgroundColor = [[NSColor unemphasizedSelectedContentBackgroundColor] CGColor];
+        return;
+    }
     if (!style) style = objc_getAssociatedObject(v, "aeui_styled_bg");
-    if (!style) return;
+    if (!style) {
+        // Nothing to paint: a row that just lost its selection goes back to
+        // no ground of its own.
+        if (objc_getAssociatedObject(v, "aeui-row-selection-painted")) {
+            objc_setAssociatedObject(v, "aeui-row-selection-painted", nil, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
+            if (v.layer) v.layer.backgroundColor = NULL;
+        }
+        return;
+    }
     int packed = [style intValue];
     if (!(packed & 0x1000000)) return;
     [v setWantsLayer:YES];
@@ -4308,19 +4326,36 @@ static int class_list_has(const char* list, const char* cls) {
     return 0;
 }
 
+// A class is a name the driver reads back, and on GTK4 a stylesheet's hook.
+// One has a look here as well: .aui-row-selected, the listbox's selection,
+// which every list on every backend has to show (see aeui_apply_state_bg).
+static void aeui_class_visual(int handle, const char* cls, int on) {
+    if (strcmp(cls, "aui-row-selected") != 0) return;
+    NSView* v = (__bridge NSView*)aether_ui_get_widget(handle);
+    if (!v) return;
+    objc_setAssociatedObject(v, "aeui-row-selected", on ? @(1) : nil,
+                             OBJC_ASSOCIATION_RETAIN_NONATOMIC);
+    if (on) objc_setAssociatedObject(v, "aeui-row-selection-painted", @(1),
+                                     OBJC_ASSOCIATION_RETAIN_NONATOMIC);
+    aeui_apply_state_bg(v);
+    [v setNeedsDisplay:YES];
+}
+
 void aether_ui_widget_add_css_class_impl(int handle, const char* cls) {
     if (handle < 1 || handle > widget_count || !cls || !*cls) return;
     char* cur = widget_classes[handle - 1];
     if (class_list_has(cur, cls)) return;  // idempotent, like GTK's
     if (!cur) {
         widget_classes[handle - 1] = strdup(cls);
+        aeui_class_visual(handle, cls, 1);
         return;
     }
     char* joined = (char*)malloc(strlen(cur) + strlen(cls) + 2);
     if (!joined) return;
     sprintf(joined, "%s %s", cur, cls);
     free(cur);
     widget_classes[handle - 1] = joined;
+    aeui_class_visual(handle, cls, 1);
 }
 
 void aether_ui_widget_remove_css_class_impl(int handle, const char* cls) {
@@ -4341,6 +4376,7 @@ void aether_ui_widget_remove_css_class_impl(int handle, const char* cls) {
     free(work);
     free(cur);
     widget_classes[handle - 1] = out;  // "" when the last class was removed
+    aeui_class_visual(handle, cls, 0);
 }
 // ---------------------------------------------------------------------------
 // The drawn tooltip — a vg-drawn shape's tooltip, rendered as an overlay

backend/aether_ui_uikit.m

@@ -2934,10 +2934,33 @@ void aether_ui_widget_weight_impl(int handle, int n) {
 }
 
 // --- CSS classes (per-widget, space-separated; drives selectors + the driver)
+// A class is a name the driver reads back, and on GTK4 a stylesheet's hook.
+// One has a look here as well: .aui-row-selected, the listbox's selection,
+// which every list on every backend has to show. The system fill is the
+// tint an iOS list draws under a selected cell; the row's own colour is
+// kept and comes back when the selection leaves.
+static void aeui_class_visual(int handle, const char* cls, int on) {
+    if (strcmp(cls, "aui-row-selected") != 0) return;
+    UIView* v = (__bridge UIView*)aether_ui_get_widget(handle);
+    if (!v) return;
+    if (on) {
+        if (!objc_getAssociatedObject(v, "aeui-row-orig"))
+            objc_setAssociatedObject(v, "aeui-row-orig", v.backgroundColor ?: [NSNull null],
+                                     OBJC_ASSOCIATION_RETAIN_NONATOMIC);
+        v.backgroundColor = [UIColor tertiarySystemFillColor];
+    } else {
+        id orig = objc_getAssociatedObject(v, "aeui-row-orig");
+        if (orig) {
+            v.backgroundColor = (orig == [NSNull null]) ? nil : orig;
+            objc_setAssociatedObject(v, "aeui-row-orig", nil, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
+        }
+    }
+}
+
 void aether_ui_widget_add_css_class_impl(int handle, const char* cls) {
     if (handle < 1 || handle > widget_count || !cls || !cls[0]) return;
     char* cur = widget_classes[handle - 1];
-    if (!cur) { widget_classes[handle - 1] = strdup(cls); return; }
+    if (!cur) { widget_classes[handle - 1] = strdup(cls); aeui_class_visual(handle, cls, 1); return; }
     // Already present? (whole-token match)
     size_t clen = strlen(cls);
     const char* p = cur;
@@ -2952,6 +2975,7 @@ void aether_ui_widget_add_css_class_impl(int handle, const char* cls) {
     snprintf(joined, n, "%s %s", cur, cls);
     free(cur);
     widget_classes[handle - 1] = joined;
+    aeui_class_visual(handle, cls, 1);
 }
 void aether_ui_widget_remove_css_class_impl(int handle, const char* cls) {
     if (handle < 1 || handle > widget_count || !cls || !cls[0]) return;
@@ -2973,6 +2997,7 @@ void aether_ui_widget_remove_css_class_impl(int handle, const char* cls) {
     }
     free(cur);
     widget_classes[handle - 1] = out[0] ? out : (free(out), (char*)NULL);
+    aeui_class_visual(handle, cls, 0);
 }
 const char* aether_ui_widget_classes_impl(int handle) {
     if (handle < 1 || handle > widget_count) return "";