Layout: review r3 fix

docs/components/003-status-bar.md

@@ -47,6 +47,7 @@ if bar.Clicked == "bell" {
 - 操作条目：悬停 SurfaceHover，按下 Selection，键盘焦点环。
 - 折叠：按“右组末项 → 左组首项”的顺序隐藏 `Secondary` 条目，直到放得下（按实际宽度计算，操作条目至少 28 DIP，含条目间距）；显示 `+N` 按钮，无障碍名称为“另有 N 项”，点击或 Enter/Space 打开弹层，列出被隐藏的条目，其中的操作照常可用，执行后弹层关闭。主要条目永不隐藏。
 - 文本放大时状态栏随文字增高。
+- 焦点所在条目被折叠时，焦点移到收纳它的 `+N` 按钮上，不会丢失。
 - 进度：AccentText 填充，Border 轨道，描述为百分比。
 
 ## 事件

status_bar.go

@@ -70,19 +70,25 @@ func StatusBar(c *ui.Context, opts StatusBarOptions) StatusBarResult {
 	hidden := statusBarHide(c, opts, was.W-d.Unit()*4, gap)
 	open := ui.Local(e, "status_bar.open", func() bool { return false })
 	*open = *open && len(hidden) > 0
+	// focused is the bar item that had the focus last frame, for moving it to "+N" when that item folds.
+	focused := ui.Local(e, "status_bar.focused", func() string { return "" })
+	wasFocused := *focused
+	*focused = ""
 	var res StatusBarResult
-	item := func(it StatusItem) {
-		if statusBarItem(c, it) {
+	item := func(it StatusItem) bool {
+		clicked, hasFocus := statusBarItem(c, it)
+		if clicked {
 			res.Clicked = it.ID
 			*open = false
 			slog.Debug("mujica: status_bar clicked", "id", it.ID)
 		}
+		return hasFocus
 	}
 	group := func(key string, items []StatusItem) {
 		ui.Row(c).Key(key).Gap(gap).Shrink(0).Dividers(theme.BorderWidth, k.Border).Children(func() {
 			for _, it := range items {
-				if !hidden[it.ID] {
-					item(it)
+				if !hidden[it.ID] && item(it) {
+					*focused = it.ID
 				}
 			}
 		})
@@ -92,6 +98,10 @@ func StatusBar(c *ui.Context, opts StatusBarOptions) StatusBarResult {
 		ui.Spacer(c).Key("status_bar.spacer")
 		if len(hidden) > 0 {
 			more := statusBarMore(c, len(hidden))
+			if wasFocused != "" && hidden[wasFocused] {
+				more.Focus()
+				slog.Debug("mujica: status_bar focus folded", "id", wasFocused)
+			}
 			if more.Clicked() {
 				*open = !*open
 				slog.Debug("mujica: status_bar hidden items", "open", *open)
@@ -217,8 +227,8 @@ func statusBarWidth(c *ui.Context, it StatusItem) float32 {
 	return w
 }
 
-// statusBarItem builds one item and reports whether its action was clicked.
-func statusBarItem(c *ui.Context, it StatusItem) bool {
+// statusBarItem builds one item and reports whether its action was clicked and whether it has the focus.
+func statusBarItem(c *ui.Context, it StatusItem) (clicked, focused bool) {
 	k := Tokens(c)
 	d := Density(c)
 	fg := k.TextMuted
@@ -265,7 +275,7 @@ func statusBarItem(c *ui.Context, it StatusItem) bool {
 			statusBarProgress(c, it.Progress)
 		}
 	})
-	return it.Action && e.Clicked()
+	return it.Action && e.Clicked(), e.FocusWithin()
 }
 
 func statusBarProgress(c *ui.Context, v float32) {

status_bar_test.go

@@ -286,3 +286,39 @@ func TestStatusBarKeepsFocusAcrossDensity(t *testing.T) {
 		t.Fatalf("Enter after the switch activated %d times, want 1", n)
 	}
 }
+
+func TestStatusBarFocusMovesToMoreWhenFocusedItemFolds(t *testing.T) {
+	density := theme.Default
+	var clicked []string
+	o := StatusBarOptions{
+		Left:  []StatusItem{{ID: "main", Text: "main"}, {ID: "fmt", Text: "Format", Action: true, Secondary: true}},
+		Right: []StatusItem{{ID: "bell", Label: "Notifications", Icon: icons.Must("bell"), Action: true}},
+	}
+	tt := ui.NewTester(func(c *ui.Context) {
+		Use(c, Settings{Density: density})
+		if id := StatusBar(c, o).Clicked; id != "" {
+			clicked = append(clicked, id)
+		}
+	}, 152, 300)
+	tt.Key(0, ui.KeyTab)
+	if !tt.Focused("Format") {
+		t.Fatal("Tab did not focus Format at Default density")
+	}
+	density = theme.Comfortable
+	tt.Frame()
+	if tt.HasText("Format") {
+		t.Fatal("Format did not fold at Comfortable density")
+	}
+	if !tt.Focused("1 more items") {
+		t.Fatal("focus did not move to the +N button that holds Format")
+	}
+	tt.Key(0, ui.KeyEnter)
+	if !tt.HasText("Format") {
+		t.Fatal("Enter on +N did not open the list with Format")
+	}
+	tt.Key(0, ui.KeyTab)
+	tt.Key(0, ui.KeyEnter)
+	if len(clicked) != 1 || clicked[0] != "fmt" {
+		t.Fatalf("clicked %v, want [fmt]", clicked)
+	}
+}