From 8880865021747432987e7fa6eca25581efb5e05e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E9=9B=B7=E7=94=B5=E8=8A=BD=E8=A1=A3?=
 <zhangyanghaha0407@outlook.com>
Date: Mon, 5 Oct 2026 13:35:53 -0400
Subject: [PATCH] Refactor: results expose Element as a named field

Every component result type now names its element Element instead of
embedding *ui.Element. The eleven element-plus-changed results
(AccordionView, CarouselView, CollapsibleView, ImageViewerView,
PaginationResult, StepsResult, SidebarResult, TabsResult, RatingParts,
FileDropZoneParts, TransferParts) fold into ChoiceResult.

Fixes four Gallery demos where .Width(...).Changed() read the element's
flag instead of the component's: Accordion, MultiSelect, Cascader,
TreeSelect. TestDataAccordionDemoLogsChange covers the Accordion.
---
 accordion.go                               | 15 +++----------
 app_shell.go                               |  2 +-
 breadcrumb.go                              |  4 ++--
 button_group.go                            |  2 +-
 carousel.go                                | 25 +++++++---------------
 carousel_test.go                           |  6 +++---
 collapsible.go                             | 15 +++----------
 command_palette.go                         |  4 ++--
 data_table.go                              |  4 ++--
 data_table_test.go                         |  4 ++--
 datetime.go                                |  2 +-
 description_list.go                        | 10 ++++-----
 docs/components/001-app-shell.md           |  2 +-
 docs/components/008-split-pane.md          |  4 ++--
 docs/components/024-text-input.md          |  2 +-
 docs/components/046-rating.md              |  2 +-
 docs/components/049-file-drop-zone.md      |  2 +-
 docs/components/050-transfer.md            |  2 +-
 docs/components/051-calendar.md            |  2 +-
 docs/components/052-date-picker.md         |  2 +-
 docs/components/053-date-range-picker.md   |  2 +-
 docs/components/054-time-picker.md         |  2 +-
 docs/components/055-time-range-picker.md   |  2 +-
 docs/components/056-date-time-picker.md    |  2 +-
 docs/components/057-month-picker.md        |  2 +-
 docs/components/058-year-picker.md         |  2 +-
 docs/components/059-tabs.md                |  4 ++--
 docs/components/061-breadcrumb.md          |  2 +-
 docs/components/062-pagination.md          |  4 ++--
 docs/components/063-steps.md               |  4 ++--
 docs/components/064-sidebar.md             |  4 ++--
 docs/components/066-menubar.md             |  2 +-
 docs/components/070-list.md                |  4 ++--
 docs/components/071-data-table.md          |  2 +-
 docs/components/072-tree.md                |  2 +-
 docs/components/073-tree-table.md          |  2 +-
 docs/components/074-accordion.md           |  4 ++--
 docs/components/075-collapsible.md         |  4 ++--
 docs/components/079-image-viewer.md        |  4 ++--
 docs/components/080-carousel.md            |  6 +++---
 example_data_test.go                       | 10 ++++-----
 example_layout_test.go                     |  2 +-
 examples/gallery/composite_files.go        |  4 ++--
 examples/gallery/pages_choice.go           | 11 +++++++---
 examples/gallery/pages_data_collections.go |  8 +++----
 examples/gallery/pages_data_content.go     |  8 ++++---
 examples/gallery/pages_data_test.go        | 10 +++++++++
 examples/gallery/pages_input.go            | 10 ++++-----
 examples/gallery/pages_layout.go           |  2 +-
 file_drop_zone.go                          | 15 +++----------
 image_viewer.go                            | 15 +++----------
 list.go                                    |  4 ++--
 list_test.go                               |  6 +++---
 menubar.go                                 |  4 ++--
 pagination.go                              | 15 +++----------
 rating.go                                  | 13 ++---------
 rating_test.go                             |  2 +-
 sidebar.go                                 | 13 ++---------
 sidebar_test.go                            |  2 +-
 slider_test.go                             |  2 +-
 split_pane.go                              |  2 +-
 split_pane_test.go                         | 10 ++++-----
 status_bar.go                              |  2 +-
 steps.go                                   | 13 ++---------
 tabs.go                                    | 13 ++---------
 tabs_test.go                               |  2 +-
 text_input.go                              |  2 +-
 toggle_group.go                            |  2 +-
 transfer.go                                | 13 ++---------
 tree.go                                    |  4 ++--
 tree_table.go                              |  2 +-
 tree_table_test.go                         |  8 +++----
 tree_test.go                               |  8 +++----
 73 files changed, 163 insertions(+), 245 deletions(-)

diff --git a/accordion.go b/accordion.go
index a13e865..4e752f7 100644
--- a/accordion.go
+++ b/accordion.go
@@ -28,17 +28,8 @@ type AccordionOptions struct {
 	KeepOne bool
 }
 
-// AccordionView is a built Accordion and what happened to it in this frame.
-type AccordionView struct {
-	*ui.Element
-	changed bool
-}
-
-// Changed reports that a section opened or closed.
-func (v AccordionView) Changed() bool { return v.changed }
-
 // Accordion shows sections whose open IDs live in *open, which the caller controls.
-func Accordion(c *ui.Context, open *[]string, items []AccordionItem, opts AccordionOptions) AccordionView {
+func Accordion(c *ui.Context, open *[]string, items []AccordionItem, opts AccordionOptions) ChoiceResult {
 	seen := map[string]bool{}
 	for _, it := range items {
 		if it.ID == "" || seen[it.ID] || it.Content == nil {
@@ -49,10 +40,10 @@ func Accordion(c *ui.Context, open *[]string, items []AccordionItem, opts Accord
 	k := Tokens(c)
 	d := Density(c)
 	u := d.Unit()
-	var v AccordionView
+	var v ChoiceResult
 	v.Element = ui.Column(c).Background(k.Surface).Border(theme.BorderWidth, k.Border).Radius(theme.CardRadius)
 	focusTo := ui.Local(v.Element, "focus", func() int { return -1 })
-	v.Children(func() {
+	v.Element.Children(func() {
 		for i, it := range items {
 			ui.Column(c).Key(it.ID).Children(func() {
 				if i > 0 {
diff --git a/app_shell.go b/app_shell.go
index 36fdbb5..cce3dea 100644
--- a/app_shell.go
+++ b/app_shell.go
@@ -28,7 +28,7 @@ type AppShellOptions struct {
 
 // AppShellResult is an AppShell and its event in this frame.
 type AppShellResult struct {
-	*ui.Element
+	Element *ui.Element
 	// Toggled reports the sidebar opened or collapsed.
 	Toggled bool
 }
diff --git a/breadcrumb.go b/breadcrumb.go
index d0977fb..29f3e7d 100644
--- a/breadcrumb.go
+++ b/breadcrumb.go
@@ -28,8 +28,8 @@ type BreadcrumbOptions struct {
 
 // BreadcrumbResult is the built Breadcrumb.
 type BreadcrumbResult struct {
-	*ui.Element
-	chosen int
+	Element *ui.Element
+	chosen  int
 }
 
 // Chosen returns the index of the item the user activated in this frame.
diff --git a/button_group.go b/button_group.go
index ab3d6b8..061f635 100644
--- a/button_group.go
+++ b/button_group.go
@@ -28,7 +28,7 @@ type ButtonGroupOptions struct {
 
 // ButtonGroupResult is the group element and the item clicked this frame.
 type ButtonGroupResult struct {
-	*ui.Element
+	Element *ui.Element
 	clicked int
 }
 
diff --git a/carousel.go b/carousel.go
index 2b27b87..13c4406 100644
--- a/carousel.go
+++ b/carousel.go
@@ -24,15 +24,6 @@ type CarouselOptions struct {
 	Loop bool
 }
 
-// CarouselView is a built Carousel and what happened to it in this frame.
-type CarouselView struct {
-	*ui.Element
-	changed bool
-}
-
-// Changed reports a new slide.
-func (v CarouselView) Changed() bool { return v.changed }
-
 type carouselState struct {
 	paused bool
 	next   time.Time
@@ -41,7 +32,7 @@ type carouselState struct {
 }
 
 // Carousel shows slide *index of n with previous, next and position controls.
-func Carousel(c *ui.Context, index *int, n int, opts CarouselOptions, slide func(i int)) CarouselView {
+func Carousel(c *ui.Context, index *int, n int, opts CarouselOptions, slide func(i int)) ChoiceResult {
 	if n < 0 || opts.Interval < 0 {
 		panic("mujica: Carousel with negative count or Interval")
 	}
@@ -51,7 +42,7 @@ func Carousel(c *ui.Context, index *int, n int, opts CarouselOptions, slide func
 	}
 	k := Tokens(c)
 	u := Density(c).Unit()
-	var v CarouselView
+	var v ChoiceResult
 	v.Element = ui.Column(c).Gap(u * 2).Label(opts.Label)
 	st := ui.Local(v.Element, "state", func() carouselState { return carouselState{} })
 	if n > 0 && (*index < 0 || *index >= n) {
@@ -75,7 +66,7 @@ func Carousel(c *ui.Context, index *int, n int, opts CarouselOptions, slide func
 		slog.Debug("mujica: carousel slide", "index", i)
 	}
 	now := c.Now()
-	playing := opts.Autoplay && n > 1 && !st.paused && !v.Hovered() && !v.FocusWithin()
+	playing := opts.Autoplay && n > 1 && !st.paused && !v.Element.Hovered() && !v.Element.FocusWithin()
 	if !playing {
 		st.next = time.Time{}
 	} else if st.next.IsZero() {
@@ -89,16 +80,16 @@ func Carousel(c *ui.Context, index *int, n int, opts CarouselOptions, slide func
 	}
 	switch {
 	case st.dotFocus:
-	case v.Shortcut(0, ui.KeyLeft):
+	case v.Element.Shortcut(0, ui.KeyLeft):
 		goTo(*index - 1)
-	case v.Shortcut(0, ui.KeyRight):
+	case v.Element.Shortcut(0, ui.KeyRight):
 		goTo(*index + 1)
-	case v.Shortcut(0, ui.KeyHome):
+	case v.Element.Shortcut(0, ui.KeyHome):
 		goTo(0)
-	case v.Shortcut(0, ui.KeyEnd):
+	case v.Element.Shortcut(0, ui.KeyEnd):
 		goTo(n - 1)
 	}
-	v.Children(func() {
+	v.Element.Children(func() {
 		ui.Row(c).Grow(1).MinHeight(120).AlignItems(ui.Center).Gap(u * 2).Children(func() {
 			prev := Button(c, "", ButtonOptions{Variant: Ghost, Icon: icons.Must("chevron-left"), Label: msg(c, "carousel.prev"), Disabled: n < 2 || !wrap && *index == 0})
 			ui.Column(c).Grow(1).MinWidth(0).FillHeight().Clip().Background(k.Surface).Border(theme.BorderWidth, k.Border).Radius(theme.CardRadius).
diff --git a/carousel_test.go b/carousel_test.go
index 59d8435..c2c0bda 100644
--- a/carousel_test.go
+++ b/carousel_test.go
@@ -20,7 +20,7 @@ func (h *carouselHarness) view(c *ui.Context) {
 		v := Carousel(c, &h.index, 4, h.opts, func(i int) {
 			ui.Text(c, fmt.Sprintf("Window %d", i+1)).Padding(20)
 		})
-		v.Grow(1)
+		v.Element.Grow(1)
 		if v.Changed() {
 			h.changes++
 		}
@@ -126,7 +126,7 @@ func TestCarouselSnapshot(t *testing.T) {
 				ui.Column(c).Grow(1).Center().Children(func() {
 					ui.Text(c, fmt.Sprintf("Rose window %d", n+1)).FontSize(FontSize(c, 18))
 				})
-			}).Grow(1)
+			}).Element.Grow(1)
 		})
 	})
 }
@@ -135,7 +135,7 @@ func TestCarouselEmptyAutoplayKeys(t *testing.T) {
 	index := 0
 	tt := ui.NewTester(func(c *ui.Context) {
 		Use(c, Settings{})
-		Carousel(c, &index, 0, CarouselOptions{Autoplay: true}, func(int) {}).Size(300, 200)
+		Carousel(c, &index, 0, CarouselOptions{Autoplay: true}, func(int) {}).Element.Size(300, 200)
 	}, 320, 240)
 	for range 4 {
 		tt.Key(0, ui.KeyTab)
diff --git a/collapsible.go b/collapsible.go
index 262e7d2..bb9b6e5 100644
--- a/collapsible.go
+++ b/collapsible.go
@@ -19,25 +19,16 @@ type CollapsibleOptions struct {
 	Disabled bool
 }
 
-// CollapsibleView is a built Collapsible and what happened to it in this frame.
-type CollapsibleView struct {
-	*ui.Element
-	changed bool
-}
-
-// Changed reports that the trigger opened or closed the content.
-func (v CollapsibleView) Changed() bool { return v.changed }
-
 // Collapsible shows content below a trigger while *open; closed content is not built.
-func Collapsible(c *ui.Context, open *bool, opts CollapsibleOptions, content func()) CollapsibleView {
+func Collapsible(c *ui.Context, open *bool, opts CollapsibleOptions, content func()) ChoiceResult {
 	if opts.Title == "" && opts.Trigger == nil {
 		panic("mujica: Collapsible needs Title or Trigger")
 	}
 	k := Tokens(c)
 	u := Density(c).Unit()
-	var v CollapsibleView
+	var v ChoiceResult
 	v.Element = ui.Column(c).Shrink(0)
-	v.Children(func() {
+	v.Element.Children(func() {
 		was := *open
 		p := ui.CollapsibleBase(c, open)
 		tr := p.Trigger
diff --git a/command_palette.go b/command_palette.go
index 1237bbe..770411a 100644
--- a/command_palette.go
+++ b/command_palette.go
@@ -32,8 +32,8 @@ type CommandPaletteOptions struct {
 
 // CommandPaletteResult is the built CommandPalette; Element is nil while closed.
 type CommandPaletteResult struct {
-	*ui.Element
-	chosen string
+	Element *ui.Element
+	chosen  string
 }
 
 // Chosen returns the ID of the command run in this frame; running closes the palette.
diff --git a/data_table.go b/data_table.go
index 508b20a..b5ea36c 100644
--- a/data_table.go
+++ b/data_table.go
@@ -85,7 +85,7 @@ func (s *DataTableState[K]) Rows() int { return len(s.cache.view) }
 
 // DataTableView is a built DataTable and what happened to it in this frame.
 type DataTableView struct {
-	*ui.Element
+	Element                           *ui.Element
 	changed, submitted, sorted, retry bool
 }
 
@@ -114,7 +114,7 @@ func DataTable[R any, K comparable](c *ui.Context, s *DataTableState[K], rows []
 	before := s.Sort
 	var v DataTableView
 	v.Element = ui.Column(c).MinHeight(0).Gap(d.Unit() * 2)
-	v.Children(func() {
+	v.Element.Children(func() {
 		if len(rows) > 0 {
 			ui.Row(c).Justify(ui.End).Children(func() {
 				tableColumnMenu(c, dataTableMenu(opts), &s.Sort, &s.Layout, &s.Hidden)
diff --git a/data_table_test.go b/data_table_test.go
index c153dee..5929626 100644
--- a/data_table_test.go
+++ b/data_table_test.go
@@ -54,7 +54,7 @@ func (h *tableHarness) view(c *ui.Context) {
 			cols.Columns[i].Text = func(r relic) string { h.seen[r.Name]++; return text(r) }
 		}
 		v := DataTable(c, &h.st, h.rows, cols)
-		v.Size(360, 300)
+		v.Element.Size(360, 300)
 		if v.Changed() {
 			h.changes++
 		}
@@ -347,7 +347,7 @@ func TestDataTableSnapshot(t *testing.T) {
 			return h
 		})
 		ui.Column(c).Padding(16).Children(func() {
-			DataTable(c, &(*h).st, (*h).rows, (*h).opts).Size(600, 260)
+			DataTable(c, &(*h).st, (*h).rows, (*h).opts).Element.Size(600, 260)
 		})
 	})
 }
diff --git a/datetime.go b/datetime.go
index 6a9bf2c..2fff036 100644
--- a/datetime.go
+++ b/datetime.go
@@ -68,7 +68,7 @@ func (d Date) within(lo, hi Date) bool {
 
 // DateTimeResult is a date or time component and what happened to it this frame.
 type DateTimeResult struct {
-	*ui.Element
+	Element *ui.Element
 	// Input is the text field inside, for labels and focus; nil without one.
 	Input     *ui.Element
 	changed   bool
diff --git a/description_list.go b/description_list.go
index 9d89dca..93a7782 100644
--- a/description_list.go
+++ b/description_list.go
@@ -31,8 +31,8 @@ type DescriptionListOptions struct {
 
 // DescriptionListView is a built DescriptionList and what happened to it in this frame.
 type DescriptionListView struct {
-	*ui.Element
-	copied int
+	Element *ui.Element
+	copied  int
 }
 
 // Copied returns the index of the item whose value was copied in this frame.
@@ -69,15 +69,15 @@ func DescriptionList(c *ui.Context, items []DescriptionItem, opts DescriptionLis
 		}
 		return max(1, min(most, int(math.Floor(float64((w+gap)/(minW+gap))))))
 	}
-	cols := fit(v.Bounds().W)
-	v.Draw(func(p *ui.Painter, r ui.Rect) {
+	cols := fit(v.Element.Bounds().W)
+	v.Element.Draw(func(p *ui.Painter, r ui.Rect) {
 		if fit(r.W) != cols {
 			// The new width needs other columns: build again.
 			c.Invalidate()
 		}
 	})
 	now := c.Now()
-	v.Columns(cols).Children(func() {
+	v.Element.Columns(cols).Children(func() {
 		for i, it := range items {
 			cell := ui.Column(c).Gap(u).MinWidth(0)
 			if it.Span < 0 || it.Span > cols {
diff --git a/docs/components/001-app-shell.md b/docs/components/001-app-shell.md
index f3ccaca..699415f 100644
--- a/docs/components/001-app-shell.md
+++ b/docs/components/001-app-shell.md
@@ -29,7 +29,7 @@ mujica.AppShell(c, &collapsed, mujica.AppShellOptions{
 | `SidebarWidth` | `float32` | 240 | 展开时侧栏宽度（DIP）；负数 panic。 |
 | `ContentScroll` | `*ui.ScrollState` | nil | 保存主内容滚动位置；nil 时按位置保留。 |
 
-返回 `AppShellResult`，内嵌 `*ui.Element`。
+返回 `AppShellResult`，`Element` 字段是组件元素。
 
 ## 状态
 
diff --git a/docs/components/008-split-pane.md b/docs/components/008-split-pane.md
index ea1e9b6..9a4659d 100644
--- a/docs/components/008-split-pane.md
+++ b/docs/components/008-split-pane.md
@@ -11,7 +11,7 @@ split := mujica.SplitPaneState{Size: 160}
 mujica.SplitPane(c, &split, mujica.SplitPaneOptions{MinFirst: 120, Collapsible: mujica.SplitPaneFirst},
 	func() { ui.Text(c, "Files") },
 	func() { ui.Text(c, "Editor") },
-).Fill()
+).Element.Fill()
 ```
 
 签名：`func SplitPane(c *ui.Context, state *SplitPaneState, opts SplitPaneOptions, first, second func()) SplitPaneResult`
@@ -33,7 +33,7 @@ mujica.SplitPane(c, &split, mujica.SplitPaneOptions{MinFirst: 120, Collapsible:
 | `MinFirst`, `MinSecond` | `float32` | 10 单位（默认 40 DIP） | 两栏最小尺寸；负数 panic。 |
 | `Collapsible` | `SplitPaneSide` | `SplitPaneNeither` | 可折叠的栏：`SplitPaneFirst` 或 `SplitPaneSecond`。 |
 
-返回 `SplitPaneResult`，内嵌 `*ui.Element`。
+返回 `SplitPaneResult`，`Element` 字段是组件元素。
 
 ## 状态
 
diff --git a/docs/components/024-text-input.md b/docs/components/024-text-input.md
index 32d4e5f..6cdd2f5 100644
--- a/docs/components/024-text-input.md
+++ b/docs/components/024-text-input.md
@@ -15,7 +15,7 @@ if r.Submitted() {
 
 签名：`func TextInput(c *ui.Context, value *string, opts TextInputOptions) InputResult`
 
-`InputResult` 内嵌外层 `*ui.Element`，`Input` 字段是内部编辑元素，`Changed()`、`Submitted()` 报告事件。
+`InputResult` 的 `Element` 字段是外层元素，`Input` 字段是内部编辑元素，`Changed()`、`Submitted()` 报告事件。
 
 ## 参数
 
diff --git a/docs/components/046-rating.md b/docs/components/046-rating.md
index 6e7dd1c..35f1ad1 100644
--- a/docs/components/046-rating.md
+++ b/docs/components/046-rating.md
@@ -35,7 +35,7 @@ ui.Render(view, 400, 300, 1)
 
 ## 事件
 
-`RatingParts.Changed()` 用户设置了新值；同值点击不触发。
+`ChoiceResult.Changed()` 用户设置了新值；同值点击不触发。
 
 ## 键盘操作
 
diff --git a/docs/components/049-file-drop-zone.md b/docs/components/049-file-drop-zone.md
index f285161..4168091 100644
--- a/docs/components/049-file-drop-zone.md
+++ b/docs/components/049-file-drop-zone.md
@@ -36,7 +36,7 @@ ui.Render(view, 400, 300, 1)
 
 ## 事件
 
-`FileDropZoneParts.Changed()` 添加或移除了文件。被拒绝的条目只显示在组件内，可单独关闭。
+`ChoiceResult.Changed()` 添加或移除了文件。被拒绝的条目只显示在组件内，可单独关闭。
 
 ## 键盘操作
 
diff --git a/docs/components/050-transfer.md b/docs/components/050-transfer.md
index 7ace8e6..7be5399 100644
--- a/docs/components/050-transfer.md
+++ b/docs/components/050-transfer.md
@@ -34,7 +34,7 @@ ui.Render(view, 400, 300, 1)
 
 ## 事件
 
-`TransferParts.Changed()` 有条目移动。
+`ChoiceResult.Changed()` 有条目移动。
 
 ## 键盘操作
 
diff --git a/docs/components/051-calendar.md b/docs/components/051-calendar.md
index e30d0cd..a971a8f 100644
--- a/docs/components/051-calendar.md
+++ b/docs/components/051-calendar.md
@@ -19,7 +19,7 @@ ui.Render(view, 400, 300, 1)
 
 ## 参数
 
-`func Calendar(c *ui.Context, value *Date, opts CalendarOptions) DateTimeResult`，返回值嵌入 `*ui.Element`。
+`func Calendar(c *ui.Context, value *Date, opts CalendarOptions) DateTimeResult`，返回值的 `Element` 字段是组件元素。
 
 | 字段 | 类型 | 默认值 | 含义 |
 | --- | --- | --- | --- |
diff --git a/docs/components/052-date-picker.md b/docs/components/052-date-picker.md
index 0a3352c..abe7c9a 100644
--- a/docs/components/052-date-picker.md
+++ b/docs/components/052-date-picker.md
@@ -21,7 +21,7 @@ ui.Render(view, 400, 300, 1)
 
 ## 参数
 
-`func DatePicker(c *ui.Context, value *Date, opts DatePickerOptions) DateTimeResult`，返回值嵌入 `*ui.Element`。
+`func DatePicker(c *ui.Context, value *Date, opts DatePickerOptions) DateTimeResult`，返回值的 `Element` 字段是组件元素。
 
 | 字段 | 类型 | 默认值 | 含义 |
 | --- | --- | --- | --- |
diff --git a/docs/components/053-date-range-picker.md b/docs/components/053-date-range-picker.md
index 9a50075..14549cd 100644
--- a/docs/components/053-date-range-picker.md
+++ b/docs/components/053-date-range-picker.md
@@ -20,7 +20,7 @@ ui.Render(view, 400, 300, 1)
 
 ## 参数
 
-`func DateRangePicker(c *ui.Context, value *DateRange, opts DateRangePickerOptions) DateTimeResult`，返回值嵌入 `*ui.Element`。
+`func DateRangePicker(c *ui.Context, value *DateRange, opts DateRangePickerOptions) DateTimeResult`，返回值的 `Element` 字段是组件元素。
 
 | 字段 | 类型 | 默认值 | 含义 |
 | --- | --- | --- | --- |
diff --git a/docs/components/054-time-picker.md b/docs/components/054-time-picker.md
index 0014447..8efb00d 100644
--- a/docs/components/054-time-picker.md
+++ b/docs/components/054-time-picker.md
@@ -20,7 +20,7 @@ ui.Render(view, 400, 300, 1)
 
 ## 参数
 
-`func TimePicker(c *ui.Context, value *TimeOfDay, opts TimePickerOptions) DateTimeResult`，返回值嵌入 `*ui.Element`。
+`func TimePicker(c *ui.Context, value *TimeOfDay, opts TimePickerOptions) DateTimeResult`，返回值的 `Element` 字段是组件元素。
 
 | 字段 | 类型 | 默认值 | 含义 |
 | --- | --- | --- | --- |
diff --git a/docs/components/055-time-range-picker.md b/docs/components/055-time-range-picker.md
index 4aac9bf..03f1a27 100644
--- a/docs/components/055-time-range-picker.md
+++ b/docs/components/055-time-range-picker.md
@@ -20,7 +20,7 @@ ui.Render(view, 400, 300, 1)
 
 ## 参数
 
-`func TimeRangePicker(c *ui.Context, value *TimeRange, opts TimeRangePickerOptions) DateTimeResult`，返回值嵌入 `*ui.Element`。
+`func TimeRangePicker(c *ui.Context, value *TimeRange, opts TimeRangePickerOptions) DateTimeResult`，返回值的 `Element` 字段是组件元素。
 
 | 字段 | 类型 | 默认值 | 含义 |
 | --- | --- | --- | --- |
diff --git a/docs/components/056-date-time-picker.md b/docs/components/056-date-time-picker.md
index d2a7efa..f3eaf42 100644
--- a/docs/components/056-date-time-picker.md
+++ b/docs/components/056-date-time-picker.md
@@ -24,7 +24,7 @@ ui.Render(view, 400, 300, 1)
 
 ## 参数
 
-`func DateTimePicker(c *ui.Context, value *time.Time, opts DateTimePickerOptions) DateTimeResult`，返回值嵌入 `*ui.Element`。
+`func DateTimePicker(c *ui.Context, value *time.Time, opts DateTimePickerOptions) DateTimeResult`，返回值的 `Element` 字段是组件元素。
 
 | 字段 | 类型 | 默认值 | 含义 |
 | --- | --- | --- | --- |
diff --git a/docs/components/057-month-picker.md b/docs/components/057-month-picker.md
index 562bf37..4179854 100644
--- a/docs/components/057-month-picker.md
+++ b/docs/components/057-month-picker.md
@@ -20,7 +20,7 @@ ui.Render(view, 400, 300, 1)
 
 ## 参数
 
-`func MonthPicker(c *ui.Context, value *YearMonth, opts MonthPickerOptions) DateTimeResult`，返回值嵌入 `*ui.Element`。
+`func MonthPicker(c *ui.Context, value *YearMonth, opts MonthPickerOptions) DateTimeResult`，返回值的 `Element` 字段是组件元素。
 
 | 字段 | 类型 | 默认值 | 含义 |
 | --- | --- | --- | --- |
diff --git a/docs/components/058-year-picker.md b/docs/components/058-year-picker.md
index d832172..4e1d204 100644
--- a/docs/components/058-year-picker.md
+++ b/docs/components/058-year-picker.md
@@ -20,7 +20,7 @@ ui.Render(view, 400, 300, 1)
 
 ## 参数
 
-`func YearPicker(c *ui.Context, value *int, opts YearPickerOptions) DateTimeResult`，返回值嵌入 `*ui.Element`。
+`func YearPicker(c *ui.Context, value *int, opts YearPickerOptions) DateTimeResult`，返回值的 `Element` 字段是组件元素。
 
 | 字段 | 类型 | 默认值 | 含义 |
 | --- | --- | --- | --- |
diff --git a/docs/components/059-tabs.md b/docs/components/059-tabs.md
index 436f668..ec6257e 100644
--- a/docs/components/059-tabs.md
+++ b/docs/components/059-tabs.md
@@ -14,7 +14,7 @@ mujica.Tabs(c, &tab, []mujica.Tab{
 }, mujica.TabsOptions{Label: "Settings"})
 ```
 
-签名：`func Tabs(c *ui.Context, selected *int, tabs []Tab, opts TabsOptions) TabsResult`
+签名：`func Tabs(c *ui.Context, selected *int, tabs []Tab, opts TabsOptions) ChoiceResult`
 
 ## 参数
 
@@ -36,7 +36,7 @@ mujica.Tabs(c, &tab, []mujica.Tab{
 | `Vertical` | `bool` | false | 标签竖排在左侧，面板在右侧。 |
 | `Label` | `string` | "" | 标签列表的无障碍名称。 |
 
-返回 `TabsResult`，内嵌包含标签与面板的 `*ui.Element`。
+返回 `ChoiceResult`，`Element` 字段是包含标签与面板的元素。
 
 ## 状态
 
diff --git a/docs/components/061-breadcrumb.md b/docs/components/061-breadcrumb.md
index 482f51a..31829d4 100644
--- a/docs/components/061-breadcrumb.md
+++ b/docs/components/061-breadcrumb.md
@@ -33,7 +33,7 @@ if i, ok := mujica.Breadcrumb(c, path, mujica.BreadcrumbOptions{}).Chosen(); ok
 | `MaxItemWidth` | `float32` | 0（即 160 DIP） | 单项文字最大宽度，超出以省略号截断。 |
 | `Label` | `string` | 内置“路径导航” | 整组的无障碍名称。 |
 
-返回 `BreadcrumbResult`，内嵌 `*ui.Element`。
+返回 `BreadcrumbResult`，`Element` 字段是组件元素。
 
 ## 状态
 
diff --git a/docs/components/062-pagination.md b/docs/components/062-pagination.md
index 3900d93..d4fa70e 100644
--- a/docs/components/062-pagination.md
+++ b/docs/components/062-pagination.md
@@ -12,7 +12,7 @@ if mujica.Pagination(c, &page, &size, mujica.PaginationOptions{Total: 420, PageS
 }
 ```
 
-签名：`func Pagination(c *ui.Context, page, pageSize *int, opts PaginationOptions) PaginationResult`
+签名：`func Pagination(c *ui.Context, page, pageSize *int, opts PaginationOptions) ChoiceResult`
 
 ## 参数
 
@@ -28,7 +28,7 @@ if mujica.Pagination(c, &page, &size, mujica.PaginationOptions{Total: 420, PageS
 | `Siblings` | `int` | 0（即 1） | 当前页两侧显示的页码数；为负 panic。 |
 | `Disabled` | `bool` | false | 整体禁用。 |
 
-返回 `PaginationResult`，内嵌 `*ui.Element`。
+返回 `ChoiceResult`，`Element` 字段是组件元素。
 
 ## 状态
 
diff --git a/docs/components/063-steps.md b/docs/components/063-steps.md
index b9e7051..3d83ccc 100644
--- a/docs/components/063-steps.md
+++ b/docs/components/063-steps.md
@@ -14,7 +14,7 @@ mujica.Steps(c, &current, []mujica.Step{
 }, mujica.StepsOptions{Label: "Sign-up"})
 ```
 
-签名：`func Steps(c *ui.Context, current *int, steps []Step, opts StepsOptions) StepsResult`
+签名：`func Steps(c *ui.Context, current *int, steps []Step, opts StepsOptions) ChoiceResult`
 
 ## 参数
 
@@ -36,7 +36,7 @@ mujica.Steps(c, &current, []mujica.Step{
 | `Vertical` | `bool` | false | 纵向排列，连接线在标记下方。 |
 | `Label` | `string` | "" | 整组的无障碍名称。 |
 
-返回 `StepsResult`，内嵌 `*ui.Element`。
+返回 `ChoiceResult`，`Element` 字段是组件元素。
 
 ## 状态
 
diff --git a/docs/components/064-sidebar.md b/docs/components/064-sidebar.md
index ff174ed..3b76d6b 100644
--- a/docs/components/064-sidebar.md
+++ b/docs/components/064-sidebar.md
@@ -15,7 +15,7 @@ mujica.Sidebar(c, &selected, []mujica.SidebarSection{
 }, mujica.SidebarOptions{})
 ```
 
-签名：`func Sidebar(c *ui.Context, selected *string, sections []SidebarSection, opts SidebarOptions) SidebarResult`
+签名：`func Sidebar(c *ui.Context, selected *string, sections []SidebarSection, opts SidebarOptions) ChoiceResult`
 
 ## 参数
 
@@ -45,7 +45,7 @@ mujica.Sidebar(c, &selected, []mujica.SidebarSection{
 | `Compact` | `bool` | false | 图标栏：隐藏文字与组标题，组之间以旧金细线分隔，名称作为悬停提示。 |
 | `Width` | `float32` | 0（240，紧凑时 56） | 宽度，DIP。高度填满父容器。 |
 
-返回 `SidebarResult`，内嵌 `*ui.Element`。展开折叠状态由组件保存。
+返回 `ChoiceResult`，`Element` 字段是组件元素。展开折叠状态由组件保存。
 
 ## 状态
 
diff --git a/docs/components/066-menubar.md b/docs/components/066-menubar.md
index ea969cd..c78c291 100644
--- a/docs/components/066-menubar.md
+++ b/docs/components/066-menubar.md
@@ -45,7 +45,7 @@ if id, ok := res.Chosen(); ok && id == "wrap" {
 | --- | --- | --- | --- |
 | `Label` | `string` | 内置“菜单栏” | 菜单栏的无障碍名称。 |
 
-返回 `MenubarResult`，内嵌菜单栏 `*ui.Element`。
+返回 `MenubarResult`，`Element` 字段是菜单栏元素。
 
 ## 状态
 
diff --git a/docs/components/070-list.md b/docs/components/070-list.md
index 3623837..d8f9667 100644
--- a/docs/components/070-list.md
+++ b/docs/components/070-list.md
@@ -15,7 +15,7 @@ view := func(c *ui.Context) {
 		Key:   func(i int) string { return names[i] },
 		Label: func(i int) string { return names[i] },
 	}, func(i int) { ui.Text(c, names[i]) })
-	v.Size(240, 200)
+	v.Element.Size(240, 200)
 	if v.Changed() {
 		key, _ := state.Selected()
 		fmt.Println("chose", key)
@@ -26,7 +26,7 @@ ui.Render(view, 400, 300, 1)
 
 ## 参数
 
-`func List[K comparable](c *ui.Context, s *ListState[K], n int, opts ListOptions[K], item func(i int)) ListView`。`ListView` 嵌入 `*ui.Element`；`ListState` 由调用方持有，零值表示未选择。`state.Selected()` 返回所选键，多选时 `state.Selection` 保存全部键；`state.ScrollTo(i)` 滚动到第 i 项。
+`func List[K comparable](c *ui.Context, s *ListState[K], n int, opts ListOptions[K], item func(i int)) ListView`。`ListView` 的 `Element` 字段是列表元素；`ListState` 由调用方持有，零值表示未选择。`state.Selected()` 返回所选键，多选时 `state.Selection` 保存全部键；`state.ScrollTo(i)` 滚动到第 i 项。
 
 | 字段 | 类型 | 默认值 | 含义 |
 | --- | --- | --- | --- |
diff --git a/docs/components/071-data-table.md b/docs/components/071-data-table.md
index 68ab9d8..f62dbb4 100644
--- a/docs/components/071-data-table.md
+++ b/docs/components/071-data-table.md
@@ -27,7 +27,7 @@ opts := mujica.DataTableOptions[relic, int]{
 }
 view := func(c *ui.Context) {
 	mujica.Use(c, mujica.Settings{})
-	mujica.DataTable(c, &state, rows, opts).Size(360, 240)
+	mujica.DataTable(c, &state, rows, opts).Element.Size(360, 240)
 }
 ui.Render(view, 400, 300, 1)
 ```
diff --git a/docs/components/072-tree.md b/docs/components/072-tree.md
index 7b6c049..65d4244 100644
--- a/docs/components/072-tree.md
+++ b/docs/components/072-tree.md
@@ -15,7 +15,7 @@ view := func(c *ui.Context) {
 		Roots:    []string{"Nave", "Sacristy"},
 		Children: func(n string) []string { return kids[n] },
 		Label:    func(n string) string { return n },
-	}).Size(280, 240)
+	}).Element.Size(280, 240)
 }
 ui.Render(view, 400, 300, 1)
 ```
diff --git a/docs/components/073-tree-table.md b/docs/components/073-tree-table.md
index dac451b..ae408ad 100644
--- a/docs/components/073-tree-table.md
+++ b/docs/components/073-tree-table.md
@@ -22,7 +22,7 @@ view := func(c *ui.Context) {
 			{ID: "size", Title: "Size", Width: 80, Align: ui.End,
 				Cell: func(n string) { ui.Text(c, strconv.Itoa(size[n])) }},
 		},
-	}).Size(360, 240)
+	}).Element.Size(360, 240)
 }
 ui.Render(view, 400, 300, 1)
 ```
diff --git a/docs/components/074-accordion.md b/docs/components/074-accordion.md
index fe0a242..df78411 100644
--- a/docs/components/074-accordion.md
+++ b/docs/components/074-accordion.md
@@ -20,7 +20,7 @@ ui.Render(view, 400, 300, 1)
 
 ## 参数
 
-`func Accordion(c *ui.Context, open *[]string, items []AccordionItem, opts AccordionOptions) AccordionView`。`*open` 是展开区段的 ID 列表；`AccordionItem` 字段：`ID`（必填、唯一）、`Title`、`Content`（必填）、`Disabled`。
+`func Accordion(c *ui.Context, open *[]string, items []AccordionItem, opts AccordionOptions) ChoiceResult`。`*open` 是展开区段的 ID 列表；`AccordionItem` 字段：`ID`（必填、唯一）、`Title`、`Content`（必填）、`Disabled`。
 
 | 字段 | 类型 | 默认值 | 含义 |
 | --- | --- | --- | --- |
@@ -33,7 +33,7 @@ ui.Render(view, 400, 300, 1)
 
 ## 事件
 
-`AccordionView.Changed()`：某区段因用户操作而展开或关闭，`*open` 已更新。外部直接修改 `*open` 不触发事件。
+`ChoiceResult.Changed()`：某区段因用户操作而展开或关闭，`*open` 已更新。外部直接修改 `*open` 不触发事件。
 
 ## 键盘操作
 
diff --git a/docs/components/075-collapsible.md b/docs/components/075-collapsible.md
index 417263d..9747308 100644
--- a/docs/components/075-collapsible.md
+++ b/docs/components/075-collapsible.md
@@ -19,7 +19,7 @@ ui.Render(view, 400, 300, 1)
 
 ## 参数
 
-`func Collapsible(c *ui.Context, open *bool, opts CollapsibleOptions, content func()) CollapsibleView`。
+`func Collapsible(c *ui.Context, open *bool, opts CollapsibleOptions, content func()) ChoiceResult`。
 
 | 字段 | 类型 | 默认值 | 含义 |
 | --- | --- | --- | --- |
@@ -33,7 +33,7 @@ ui.Render(view, 400, 300, 1)
 
 ## 事件
 
-`CollapsibleView.Changed()`：用户点击或按键切换了展开状态。
+`ChoiceResult.Changed()`：用户点击或按键切换了展开状态。
 
 ## 键盘操作
 
diff --git a/docs/components/079-image-viewer.md b/docs/components/079-image-viewer.md
index c2a038c..d0f59b4 100644
--- a/docs/components/079-image-viewer.md
+++ b/docs/components/079-image-viewer.md
@@ -18,7 +18,7 @@ ui.Render(view, 400, 300, 1)
 
 ## 参数
 
-`func ImageViewer(c *ui.Context, open *bool, index *int, images []ViewerImage) ImageViewerView`。`ViewerImage` 字段：`Source`（`*ui.Bitmap` 或 `*ui.SVG`，必填）、`Alt`（说明文字与无障碍名称）。关闭时返回的 `Element` 为 nil。
+`func ImageViewer(c *ui.Context, open *bool, index *int, images []ViewerImage) ChoiceResult`。`ViewerImage` 字段：`Source`（`*ui.Bitmap` 或 `*ui.SVG`，必填）、`Alt`（说明文字与无障碍名称）。关闭时返回的 `Element` 为 nil。
 
 | 字段 | 类型 | 默认值 | 含义 |
 | --- | --- | --- | --- |
@@ -32,7 +32,7 @@ ui.Render(view, 400, 300, 1)
 
 ## 事件
 
-`ImageViewerView.Changed()`：切换了图片，`*index` 已更新。关闭通过 `*open` 变为 false 观察。
+`ChoiceResult.Changed()`：切换了图片，`*index` 已更新。关闭通过 `*open` 变为 false 观察。
 
 ## 键盘操作
 
diff --git a/docs/components/080-carousel.md b/docs/components/080-carousel.md
index e9db9e3..6233f17 100644
--- a/docs/components/080-carousel.md
+++ b/docs/components/080-carousel.md
@@ -12,14 +12,14 @@ view := func(c *ui.Context) {
 	mujica.Use(c, mujica.Settings{})
 	mujica.Carousel(c, &index, 3, mujica.CarouselOptions{Label: "Windows", Autoplay: true}, func(i int) {
 		ui.Text(c, fmt.Sprintf("Rose window %d", i+1)).Padding(24)
-	}).Size(360, 220)
+	}).Element.Size(360, 220)
 }
 ui.Render(view, 400, 300, 1)
 ```
 
 ## 参数
 
-`func Carousel(c *ui.Context, index *int, n int, opts CarouselOptions, slide func(i int)) CarouselView`。
+`func Carousel(c *ui.Context, index *int, n int, opts CarouselOptions, slide func(i int)) ChoiceResult`。
 
 | 字段 | 类型 | 默认值 | 含义 |
 | --- | --- | --- | --- |
@@ -34,7 +34,7 @@ ui.Render(view, 400, 300, 1)
 
 ## 事件
 
-`CarouselView.Changed()`：当前项变化，`*index` 已更新；同时向读屏软件播报“第 N 项，共 M 项”。
+`ChoiceResult.Changed()`：当前项变化，`*index` 已更新；同时向读屏软件播报“第 N 项，共 M 项”。
 
 ## 键盘操作
 
diff --git a/example_data_test.go b/example_data_test.go
index a79859c..81cd578 100644
--- a/example_data_test.go
+++ b/example_data_test.go
@@ -31,7 +31,7 @@ func ExampleList() {
 			Key:   func(i int) string { return names[i] },
 			Label: func(i int) string { return names[i] },
 		}, func(i int) { ui.Text(c, names[i]) })
-		v.Size(240, 200)
+		v.Element.Size(240, 200)
 		if v.Changed() {
 			key, _ := state.Selected()
 			fmt.Println("chose", key)
@@ -61,7 +61,7 @@ func ExampleDataTable() {
 	}
 	view := func(c *ui.Context) {
 		mujica.Use(c, mujica.Settings{})
-		mujica.DataTable(c, &state, rows, opts).Size(360, 240)
+		mujica.DataTable(c, &state, rows, opts).Element.Size(360, 240)
 	}
 	ui.Render(view, 400, 300, 1)
 }
@@ -75,7 +75,7 @@ func ExampleTree() {
 			Roots:    []string{"Nave", "Sacristy"},
 			Children: func(n string) []string { return kids[n] },
 			Label:    func(n string) string { return n },
-		}).Size(280, 240)
+		}).Element.Size(280, 240)
 	}
 	ui.Render(view, 400, 300, 1)
 }
@@ -96,7 +96,7 @@ func ExampleTreeTable() {
 				{ID: "size", Title: "Size", Width: 80, Align: ui.End,
 					Cell: func(n string) { ui.Text(c, strconv.Itoa(size[n])) }},
 			},
-		}).Size(360, 240)
+		}).Element.Size(360, 240)
 	}
 	ui.Render(view, 400, 300, 1)
 }
@@ -176,7 +176,7 @@ func ExampleCarousel() {
 		mujica.Use(c, mujica.Settings{})
 		mujica.Carousel(c, &index, 3, mujica.CarouselOptions{Label: "Windows", Autoplay: true}, func(i int) {
 			ui.Text(c, fmt.Sprintf("Rose window %d", i+1)).Padding(24)
-		}).Size(360, 220)
+		}).Element.Size(360, 220)
 	}
 	ui.Render(view, 400, 300, 1)
 }
diff --git a/example_layout_test.go b/example_layout_test.go
index 2926e55..e3e4b19 100644
--- a/example_layout_test.go
+++ b/example_layout_test.go
@@ -100,7 +100,7 @@ func ExampleSplitPane() {
 		mujica.SplitPane(c, &split, mujica.SplitPaneOptions{MinFirst: 120, Collapsible: mujica.SplitPaneFirst},
 			func() { ui.Text(c, "Files") },
 			func() { ui.Text(c, "Editor") },
-		).Fill()
+		).Element.Fill()
 	}
 	ui.Render(view, 400, 300, 1)
 }
diff --git a/examples/gallery/composite_files.go b/examples/gallery/composite_files.go
index b42b472..0ceda62 100644
--- a/examples/gallery/composite_files.go
+++ b/examples/gallery/composite_files.go
@@ -152,7 +152,7 @@ func (g *gallery) filesView(c *ui.Context, log func(string)) {
 		v := mujica.DataTable(c, &s.table, s.entries, mujica.DataTableOptions[fileEntry, int]{
 			Columns: cols, Key: func(f fileEntry) int { return f.ID }, Multiple: true, Version: s.version,
 		})
-		v.FillWidth().Height(430)
+		v.Element.FillWidth().Height(430)
 		mujica.ContextMenu(c, v.Element, mujica.ContextMenuOptions{}, func(m *mujica.PopupMenu) { g.fileMenu(m, log, targets) })
 		if v.Changed() {
 			log(fmt.Sprintf("selection %d checked", s.table.Selection.Len()))
@@ -174,7 +174,7 @@ func (g *gallery) filesView(c *ui.Context, log func(string)) {
 			{ID: "shown", Text: fmt.Sprintf(g.t("%d shown", "显示 %d 个"), shown), Secondary: true},
 		},
 		Right: []mujica.StatusItem{{ID: "selected", Text: fmt.Sprintf(g.t("%d selected", "已选 %d 个"), s.table.Selection.Len())}},
-	}).Radius(theme.CardRadius).Border(theme.BorderWidth, k.Border)
+	}).Element.Radius(theme.CardRadius).Border(theme.BorderWidth, k.Border)
 	g.fileAdders(c, log)
 	g.renameDialog(c, log)
 	g.deleteDialog(c, log)
diff --git a/examples/gallery/pages_choice.go b/examples/gallery/pages_choice.go
index 05adf56..d703472 100644
--- a/examples/gallery/pages_choice.go
+++ b/examples/gallery/pages_choice.go
@@ -330,7 +330,8 @@ func multiSelectDemo(c *ui.Context, log func(string)) {
 		}
 		choiceLabeled(c, "Fruits", func() {
 			r := mujica.MultiSelect(c, &s.values, choiceFruits, mujica.MultiSelectOptions{Max: limit, MaxTags: 2, Disabled: s.disable, Label: "Fruits"})
-			if r.Width(320).Changed() {
+			r.Element.Width(320)
+			if r.Changed() {
 				log(fmt.Sprintf("Fruits: %v", s.values))
 			}
 		})
@@ -435,7 +436,9 @@ func cascaderDemo(c *ui.Context, log func(string)) {
 	}, func() {
 		choiceLabeled(c, "City (children load on demand)", func() {
 			opts := mujica.CascaderOptions{Level: level, Load: load, AnyLevel: s.anyLevel, Disabled: s.ds, Label: "City"}
-			if mujica.Cascader(c, &s.path, opts).Width(320).Changed() {
+			r := mujica.Cascader(c, &s.path, opts)
+			r.Element.Width(320)
+			if r.Changed() {
 				log(fmt.Sprintf("path: %v", s.path))
 			}
 		})
@@ -471,7 +474,9 @@ func treeSelectDemo(c *ui.Context, log func(string)) {
 		}
 		choiceLabeled(c, "Roles", func() {
 			opts := mujica.TreeSelectOptions{Multiple: s.multiple, Rule: rule, MaxTags: 2, Disabled: s.disabled, Label: "Roles"}
-			if mujica.TreeSelect(c, &s.sel, choiceRoles, opts).Width(320).Changed() {
+			r := mujica.TreeSelect(c, &s.sel, choiceRoles, opts)
+			r.Element.Width(320)
+			if r.Changed() {
 				log(fmt.Sprintf("Roles: %v", s.sel))
 			}
 		})
diff --git a/examples/gallery/pages_data_collections.go b/examples/gallery/pages_data_collections.go
index 0b37378..4d469d5 100644
--- a/examples/gallery/pages_data_collections.go
+++ b/examples/gallery/pages_data_collections.go
@@ -58,7 +58,7 @@ func dataListDemo(c *ui.Context, log func(string)) {
 				ui.Text(c, "Office").TextColor(mujica.Tokens(c).TextMuted)
 			}
 		})
-		v.Size(480, 320)
+		v.Element.Size(480, 320)
 		if v.Changed() {
 			k, _ := s.list.Selected()
 			log(fmt.Sprintf("selected %d, %d chosen", k, s.list.Selection.Len()))
@@ -138,7 +138,7 @@ func dataTableDemo(c *ui.Context, log func(string)) {
 		v := mujica.DataTable(c, &s.table, rows, mujica.DataTableOptions[dataRelic, int]{
 			Columns: cols, Key: func(r dataRelic) int { return r.ID }, Multiple: s.multiple, Status: st,
 		})
-		v.Size(620, 360)
+		v.Element.Size(620, 360)
 		ui.Text(c, fmt.Sprintf("%d of %d rows shown", s.table.Rows(), len(rows))).TextColor(k.TextMuted)
 		if v.SortChanged() {
 			log(fmt.Sprintf("sort %s descending=%v", s.table.Sort.Column, s.table.Sort.Descending))
@@ -224,7 +224,7 @@ func dataTreeDemo(c *ui.Context, log func(string)) {
 			ui.Checkbox(c, &s.multiple, "Multiple")
 		})
 		v := mujica.Tree(c, ts, opts)
-		v.Size(420, 340)
+		v.Element.Size(420, 340)
 		if v.Changed() {
 			n, _ := ts.Selected()
 			log(fmt.Sprintf("selected %s, %d chosen", n, ts.Selection.Len()))
@@ -290,7 +290,7 @@ func dataTreeTableDemo(c *ui.Context, log func(string)) {
 				{ID: "kids", Title: "Rooms", Width: 80, Align: ui.End, Cell: func(n string) { ui.Text(c, strconv.Itoa(len(s.lazy.kids[n]))) }},
 			},
 		})
-		v.Size(520, 320)
+		v.Element.Size(520, 320)
 		if v.SortChanged() {
 			log(fmt.Sprintf("sort %s descending=%v", s.table.Sort.Column, s.table.Sort.Descending))
 		}
diff --git a/examples/gallery/pages_data_content.go b/examples/gallery/pages_data_content.go
index 92d1b95..6e93449 100644
--- a/examples/gallery/pages_data_content.go
+++ b/examples/gallery/pages_data_content.go
@@ -58,7 +58,7 @@ func dataAccordionDemo(c *ui.Context, log func(string)) {
 				log("closed all from outside")
 			}
 		})
-		if mujica.Accordion(c, &s.open, []mujica.AccordionItem{
+		r := mujica.Accordion(c, &s.open, []mujica.AccordionItem{
 			{ID: "choir", Title: "Choir", Content: func() { ui.Text(c, "Twelve voices, two at the altar.") }},
 			{ID: "nave", Title: "Nave", Content: func() { ui.Text(c, "Pews of black oak, polished for the feast.") }},
 			{ID: "crypt", Title: "Crypt (disabled)", Disabled: true, Content: func() {}},
@@ -67,7 +67,9 @@ func dataAccordionDemo(c *ui.Context, log func(string)) {
 					log("ring the bells")
 				}
 			}},
-		}, mujica.AccordionOptions{Multiple: s.multiple, KeepOne: s.keepOne}).Width(420).Changed() {
+		}, mujica.AccordionOptions{Multiple: s.multiple, KeepOne: s.keepOne})
+		r.Element.Width(420)
+		if r.Changed() {
 			log(fmt.Sprintf("open %v", s.open))
 		}
 	})
@@ -235,7 +237,7 @@ func dataCarouselDemo(c *ui.Context, log func(string)) {
 		v := mujica.Carousel(c, &s.index, len(dataPictures), mujica.CarouselOptions{Label: "Windows", Autoplay: s.autoplay, Loop: s.loop, Interval: d}, func(i int) {
 			ui.Image(c, dataPictures[i].Source).Grow(1).Label(dataPictures[i].Alt)
 		})
-		v.Size(520, 300)
+		v.Element.Size(520, 300)
 		if v.Changed() {
 			log(fmt.Sprintf("slide %d", s.index+1))
 		}
diff --git a/examples/gallery/pages_data_test.go b/examples/gallery/pages_data_test.go
index 8593aeb..d278852 100644
--- a/examples/gallery/pages_data_test.go
+++ b/examples/gallery/pages_data_test.go
@@ -47,3 +47,13 @@ func TestDataDemoButtonsLog(t *testing.T) {
 		t.Fatalf("Light candles not logged: %q", *events)
 	}
 }
+
+func TestDataAccordionDemoLogsChange(t *testing.T) {
+	tt, events := dataDemo(t, "074")
+	if err := tt.Click("Bells"); err != nil {
+		t.Fatal(err)
+	}
+	if !slices.Contains(*events, "open [bells]") {
+		t.Fatalf("Accordion change not logged: %q", *events)
+	}
+}
diff --git a/examples/gallery/pages_input.go b/examples/gallery/pages_input.go
index f1db221..19f4ea2 100644
--- a/examples/gallery/pages_input.go
+++ b/examples/gallery/pages_input.go
@@ -180,9 +180,9 @@ if r.Submitted() {
 			inputSection(c, "States", func() {
 				ui.Row(c).Gap(12).Children(func() {
 					e, ro, off := "1789-13-01", "Read only", "Disabled"
-					mujica.TextInput(c, &e, mujica.TextInputOptions{Label: "Error state", Error: "No such date"}).Grow(1)
-					mujica.TextInput(c, &ro, mujica.TextInputOptions{Label: "Read-only state", ReadOnly: true}).Grow(1)
-					mujica.TextInput(c, &off, mujica.TextInputOptions{Label: "Disabled state", Disabled: true}).Grow(1)
+					mujica.TextInput(c, &e, mujica.TextInputOptions{Label: "Error state", Error: "No such date"}).Element.Grow(1)
+					mujica.TextInput(c, &ro, mujica.TextInputOptions{Label: "Read-only state", ReadOnly: true}).Element.Grow(1)
+					mujica.TextInput(c, &off, mujica.TextInputOptions{Label: "Disabled state", Disabled: true}).Element.Grow(1)
 				})
 			})
 		}},
@@ -244,8 +244,8 @@ if r.Submitted() {
 				ui.Row(c).Gap(12).AlignItems(ui.Start).Children(func() {
 					a, b, e := 4.0, 2.0, 7.5
 					mujica.NumberInput(c, &a, mujica.NumberInputOptions{Min: 1, Max: 8, StepperOnly: true, Label: "Stepper state"})
-					mujica.NumberInput(c, &b, mujica.NumberInputOptions{Label: "Disabled state", Disabled: true}).Width(160)
-					mujica.NumberInput(c, &e, mujica.NumberInputOptions{Step: 0.5, Label: "Error state", Error: "Must be whole"}).Width(160)
+					mujica.NumberInput(c, &b, mujica.NumberInputOptions{Label: "Disabled state", Disabled: true}).Element.Width(160)
+					mujica.NumberInput(c, &e, mujica.NumberInputOptions{Step: 0.5, Label: "Error state", Error: "Must be whole"}).Element.Width(160)
 				})
 			})
 		}},
diff --git a/examples/gallery/pages_layout.go b/examples/gallery/pages_layout.go
index a6ebd67..04d90a2 100644
--- a/examples/gallery/pages_layout.go
+++ b/examples/gallery/pages_layout.go
@@ -417,7 +417,7 @@ func layoutSplitPaneDemo(c *ui.Context, log func(string)) {
 				Collapsible: sides[s.collapsible]},
 				pane("Files", "Drag the divider, or focus it and use the arrows.", k.Surface),
 				pane("Editor", "Enter on the divider folds the collapsible pane.", k.Background))
-			r.Fill()
+			r.Element.Fill()
 			if r.Resized {
 				log(fmt.Sprintf("resized to %.0f", s.split.Size))
 			}
diff --git a/file_drop_zone.go b/file_drop_zone.go
index 5420580..828b88e 100644
--- a/file_drop_zone.go
+++ b/file_drop_zone.go
@@ -37,15 +37,6 @@ type FileDropZoneOptions struct {
 	Disabled bool
 }
 
-// FileDropZoneParts are the parts of a FileDropZone.
-type FileDropZoneParts struct {
-	Element *ui.Element
-	changed bool
-}
-
-// Changed reports whether files were added or removed this frame.
-func (p FileDropZoneParts) Changed() bool { return p.changed }
-
 // fileDropZoneReject is a file that failed a check, shown until dismissed.
 type fileDropZoneReject struct {
 	path, reason string
@@ -66,7 +57,7 @@ type fileDropZoneState struct {
 }
 
 // FileDropZone checks dropped or browsed files and lists them; it never reads or uploads them.
-func FileDropZone(c *ui.Context, files *[]DroppedFile, opts FileDropZoneOptions) FileDropZoneParts {
+func FileDropZone(c *ui.Context, files *[]DroppedFile, opts FileDropZoneOptions) ChoiceResult {
 	if opts.MaxFiles < 0 || opts.MaxSize < 0 {
 		panic("mujica: FileDropZone limits must not be negative")
 	}
@@ -77,7 +68,7 @@ func FileDropZone(c *ui.Context, files *[]DroppedFile, opts FileDropZoneOptions)
 	}
 	k := Tokens(c)
 	d := Density(c)
-	parts := FileDropZoneParts{}
+	parts := ChoiceResult{}
 	col := ui.Column(c).Gap(d.Unit() * 2)
 	parts.Element = col
 	st := ui.Local(col, "zone", func() fileDropZoneState { return fileDropZoneState{} })
@@ -213,7 +204,7 @@ func fileDropZoneCheck(c *ui.Context, st *fileDropZoneState) {
 }
 
 // fileDropZoneList shows accepted, checking and rejected files.
-func fileDropZoneList(c *ui.Context, st *fileDropZoneState, files *[]DroppedFile, parts *FileDropZoneParts, disabled bool) {
+func fileDropZoneList(c *ui.Context, st *fileDropZoneState, files *[]DroppedFile, parts *ChoiceResult, disabled bool) {
 	k := Tokens(c)
 	d := Density(c)
 	row := func(key string, icon string, color ui.Color, name, detail string, remove func()) {
diff --git a/image_viewer.go b/image_viewer.go
index 2f2fa69..a5c3ee5 100644
--- a/image_viewer.go
+++ b/image_viewer.go
@@ -20,15 +20,6 @@ type ViewerImage struct {
 	Alt string
 }
 
-// ImageViewerView is a built ImageViewer; Element is nil while closed.
-type ImageViewerView struct {
-	*ui.Element
-	changed bool
-}
-
-// Changed reports that another image was chosen.
-func (v ImageViewerView) Changed() bool { return v.changed }
-
 // Zoom limits, as multiples of the fitted size.
 const (
 	viewerMinZoom  = 0.25
@@ -42,9 +33,9 @@ type viewerState struct {
 	zoom, x, y float32
 }
 
-// ImageViewer shows images[*index] over the window while *open, with zoom, pan and switching.
-func ImageViewer(c *ui.Context, open *bool, index *int, images []ViewerImage) ImageViewerView {
-	var v ImageViewerView
+// ImageViewer shows images[*index] over the window while *open, with zoom, pan and switching; Element is nil while closed.
+func ImageViewer(c *ui.Context, open *bool, index *int, images []ViewerImage) ChoiceResult {
+	var v ChoiceResult
 	if !*open {
 		return v
 	}
diff --git a/list.go b/list.go
index 0275742..32205b0 100644
--- a/list.go
+++ b/list.go
@@ -65,7 +65,7 @@ func (s *ListState[K]) ScrollTo(i int) {
 
 // ListView is a built List and what happened to it in this frame.
 type ListView struct {
-	*ui.Element
+	Element                   *ui.Element
 	changed, submitted, retry bool
 }
 
@@ -93,7 +93,7 @@ func List[K comparable](c *ui.Context, s *ListState[K], n int, opts ListOptions[
 	k := Tokens(c)
 	var v ListView
 	v.Element = ui.Column(c).MinHeight(0)
-	v.Children(func() {
+	v.Element.Children(func() {
 		if n == 0 {
 			v.retry = dataPlaceholder(c, opts.Status, opts.Error, opts.Empty, msg(c, "list.empty"))
 			return
diff --git a/list_test.go b/list_test.go
index a3eeacb..6b8c4f8 100644
--- a/list_test.go
+++ b/list_test.go
@@ -40,7 +40,7 @@ func (h *listHarness) view(c *ui.Context) {
 			h.built++
 			ui.Text(c, h.opts.Label(i)).SingleLine()
 		})
-		v.Size(h.listSize[0], h.listSize[1])
+		v.Element.Size(h.listSize[0], h.listSize[1])
 		if v.Changed() {
 			h.changes++
 		}
@@ -207,13 +207,13 @@ func TestListSnapshot(t *testing.T) {
 		g := ui.Local(c.Root(), "g", func() *ListState[int] { return &ListState[int]{started: true, cursor: 4} })
 		opts := ListOptions[int]{Key: func(i int) int { return i }, Label: func(i int) string { return names[i] }, Multiple: true}
 		ui.Row(c).Padding(16).Gap(16).Children(func() {
-			List(c, *st, len(names), opts, func(i int) { ui.Text(c, names[i]) }).Size(220, 228)
+			List(c, *st, len(names), opts, func(i int) { ui.Text(c, names[i]) }).Element.Size(220, 228)
 			gopts := opts
 			gopts.Grid, gopts.Multiple, gopts.ItemWidth, gopts.ItemHeight = true, false, 100, 64
 			List(c, *g, len(names), gopts, func(i int) {
 				ui.Text(c, names[i]).FontWeight(600)
 				ui.Text(c, "Office").TextColor(Tokens(c).TextMuted)
-			}).Size(360, 228)
+			}).Element.Size(360, 228)
 		})
 	})
 }
diff --git a/menubar.go b/menubar.go
index e1e6189..00ce82d 100644
--- a/menubar.go
+++ b/menubar.go
@@ -56,8 +56,8 @@ type MenubarOptions struct {
 
 // MenubarResult is the built Menubar.
 type MenubarResult struct {
-	*ui.Element
-	chosen string
+	Element *ui.Element
+	chosen  string
 }
 
 // Chosen returns the ID of the item the user chose in this frame.
diff --git a/pagination.go b/pagination.go
index f73b1aa..45c2dfb 100644
--- a/pagination.go
+++ b/pagination.go
@@ -27,17 +27,8 @@ type PaginationOptions struct {
 	Disabled bool
 }
 
-// PaginationResult is the built Pagination.
-type PaginationResult struct {
-	*ui.Element
-	changed bool
-}
-
-// Changed reports a new page or page size in this frame, from the user or a correction.
-func (r PaginationResult) Changed() bool { return r.changed }
-
 // Pagination pages *page (from 1) through Total records, clamping it when Total shrinks.
-func Pagination(c *ui.Context, page, pageSize *int, opts PaginationOptions) PaginationResult {
+func Pagination(c *ui.Context, page, pageSize *int, opts PaginationOptions) ChoiceResult {
 	if opts.Total < 0 {
 		panic("mujica: Pagination Total is negative")
 	}
@@ -58,7 +49,7 @@ func Pagination(c *ui.Context, page, pageSize *int, opts PaginationOptions) Pagi
 	d := Density(c)
 	u := d.Unit()
 	row := ui.Row(c).AlignItems(ui.Center).Gap(u * 3).Wrap().Role(ui.RoleGroup).Label(msg(c, "pagination.label")).Disabled(opts.Disabled)
-	res := PaginationResult{Element: row}
+	res := ChoiceResult{Element: row}
 	pages := paginationPages(opts.Total, *pageSize)
 	if p := max(1, min(*page, pages)); p != *page {
 		slog.Debug("mujica: pagination correct", "from", *page, "to", p, "pages", pages)
@@ -166,7 +157,7 @@ func paginationButton(c *ui.Context, text string, icon *ui.SVG, name string, on,
 	return b
 }
 
-func paginationSizes(c *ui.Context, page, pageSize *int, sizes []int, res *PaginationResult) {
+func paginationSizes(c *ui.Context, page, pageSize *int, sizes []int, res *ChoiceResult) {
 	k := Tokens(c)
 	d := Density(c)
 	u := d.Unit()
diff --git a/rating.go b/rating.go
index f0110f9..1f3dea4 100644
--- a/rating.go
+++ b/rating.go
@@ -25,17 +25,8 @@ type RatingOptions struct {
 	ShowValue bool
 }
 
-// RatingParts are the parts of a Rating.
-type RatingParts struct {
-	Element *ui.Element
-	changed bool
-}
-
-// Changed reports whether the user set a new value this frame.
-func (p RatingParts) Changed() bool { return p.changed }
-
 // Rating shows *value as stars and lets the pointer and arrows set it in steps.
-func Rating(c *ui.Context, value *float64, opts RatingOptions) RatingParts {
+func Rating(c *ui.Context, value *float64, opts RatingOptions) ChoiceResult {
 	n, step := opts.Max, opts.Step
 	if n == 0 {
 		n = 5
@@ -54,7 +45,7 @@ func Rating(c *ui.Context, value *float64, opts RatingOptions) RatingParts {
 	if label == "" {
 		label = msg(c, "rating.label")
 	}
-	parts := RatingParts{}
+	parts := ChoiceResult{}
 	set := func(v float64) {
 		v = math.Max(0, math.Min(float64(n), math.Round(v/step)*step))
 		if v != *value {
diff --git a/rating_test.go b/rating_test.go
index c48634e..57d90e5 100644
--- a/rating_test.go
+++ b/rating_test.go
@@ -105,7 +105,7 @@ func TestRatingSnapshot(t *testing.T) {
 
 func TestRatingHitAreaCompact(t *testing.T) {
 	v := 2.0
-	var r RatingParts
+	var r ChoiceResult
 	tt := ui.NewTester(func(c *ui.Context) {
 		Use(c, Settings{Density: theme.Compact})
 		ui.Column(c).AlignItems(ui.Start).Children(func() {
diff --git a/sidebar.go b/sidebar.go
index fa0398d..5e5a5c5 100644
--- a/sidebar.go
+++ b/sidebar.go
@@ -37,17 +37,8 @@ type SidebarOptions struct {
 	Width float32
 }
 
-// SidebarResult is the built Sidebar.
-type SidebarResult struct {
-	*ui.Element
-	changed bool
-}
-
-// Changed reports a new choice in this frame.
-func (r SidebarResult) Changed() bool { return r.changed }
-
 // Sidebar is a source list choosing an item ID into *selected, built on MyGo's Sidebar.
-func Sidebar(c *ui.Context, selected *string, sections []SidebarSection, opts SidebarOptions) SidebarResult {
+func Sidebar(c *ui.Context, selected *string, sections []SidebarSection, opts SidebarOptions) ChoiceResult {
 	k := Tokens(c)
 	width := opts.Width
 	if width == 0 {
@@ -58,7 +49,7 @@ func Sidebar(c *ui.Context, selected *string, sections []SidebarSection, opts Si
 	}
 	wrap := ui.Column(c).Width(width).FillHeight().AlignItems(ui.Stretch).Shrink(0)
 	closed := ui.Local(wrap, "closed", func() map[string]*bool { return map[string]*bool{} })
-	res := SidebarResult{Element: wrap}
+	res := ChoiceResult{Element: wrap}
 	prev := *selected
 	wrap.Children(func() {
 		// MyGo draws icons in Accent: swap in readable state colors for the sidebar.
diff --git a/sidebar_test.go b/sidebar_test.go
index 0ae2c17..bd55bf4 100644
--- a/sidebar_test.go
+++ b/sidebar_test.go
@@ -82,7 +82,7 @@ func TestSidebarCompact(t *testing.T) {
 	tt := ui.NewTester(func(c *ui.Context) {
 		Use(c, Settings{})
 		ui.Row(c).FillHeight().Children(func() {
-			w = Sidebar(c, &sel, sidebarSample(), SidebarOptions{Compact: true}).Bounds().W
+			w = Sidebar(c, &sel, sidebarSample(), SidebarOptions{Compact: true}).Element.Bounds().W
 		})
 	}, 400, 500)
 	tt.Frame()
diff --git a/slider_test.go b/slider_test.go
index 2ebaf2e..284606f 100644
--- a/slider_test.go
+++ b/slider_test.go
@@ -90,7 +90,7 @@ func TestSliderSnapshot(t *testing.T) {
 		ui.Column(c).Padding(20).Gap(8).Width(380).Children(func() {
 			Slider(c, &a, SliderOptions{Step: 5})
 			s := Slider(c, &b, SliderOptions{Step: 25, Marks: marks, ShowValue: true, Format: func(v float64) string { return fmt.Sprintf("%.0f%%", v) }})
-			s.Focus()
+			s.Element.Focus()
 			Slider(c, &d, SliderOptions{Disabled: true})
 		})
 	})
diff --git a/split_pane.go b/split_pane.go
index 3851056..0b90209 100644
--- a/split_pane.go
+++ b/split_pane.go
@@ -39,7 +39,7 @@ type SplitPaneOptions struct {
 
 // SplitPaneResult is a SplitPane and its events in this frame.
 type SplitPaneResult struct {
-	*ui.Element
+	Element *ui.Element
 	Resized bool
 	Toggled bool
 }
diff --git a/split_pane_test.go b/split_pane_test.go
index 47fb4a2..f263d8f 100644
--- a/split_pane_test.go
+++ b/split_pane_test.go
@@ -14,7 +14,7 @@ func splitPaneTester(st *SplitPaneState, opts SplitPaneOptions, p *splitPaneProb
 	return ui.NewTester(func(c *ui.Context) {
 		Use(c, Settings{})
 		r := SplitPane(c, st, opts, func() { ui.Text(c, "Files") }, func() { ui.Text(c, "Editor") })
-		r.Fill()
+		r.Element.Fill()
 		if r.Resized {
 			p.resized++
 		}
@@ -136,7 +136,7 @@ func TestSplitPaneCollapseSecondVertical(t *testing.T) {
 	tt := ui.NewTester(func(c *ui.Context) {
 		Use(c, Settings{})
 		SplitPane(c, st, SplitPaneOptions{Vertical: true, MinSecond: 60, Collapsible: SplitPaneSecond},
-			func() { ui.Text(c, "Editor") }, func() { ui.Text(c, "Console") }).Fill()
+			func() { ui.Text(c, "Editor") }, func() { ui.Text(c, "Console") }).Element.Fill()
 	}, 300, 201)
 	tt.Key(0, ui.KeyTab)
 	tt.Key(0, ui.KeyDown)
@@ -184,7 +184,7 @@ func TestSplitPaneSnapshot(t *testing.T) {
 		}
 		ui.Column(c).Padding(16).Children(func() {
 			SplitPane(c, st, SplitPaneOptions{}, pane("Files", k.Surface), pane("Editor", k.Background)).
-				Height(128).Border(1, k.Border).Radius(4).Clip()
+				Element.Height(128).Border(1, k.Border).Radius(4).Clip()
 		})
 	})
 }
@@ -196,7 +196,7 @@ func TestSplitPaneSizesInsideBorder(t *testing.T) {
 		Use(c, Settings{})
 		SplitPane(c, st, SplitPaneOptions{MinSecond: 120}, func() { ui.Text(c, "Files") }, func() {
 			second = ui.Box(c).Fill().Absolute().Bounds()
-		}).Fill().Border(1, ui.RGB(0, 0, 0))
+		}).Element.Fill().Border(1, ui.RGB(0, 0, 0))
 	}, 401, 200)
 	tt.Key(0, ui.KeyTab)
 	tt.Key(0, ui.KeyEnd)
@@ -216,7 +216,7 @@ func TestSplitPaneClampsOnResizeAlone(t *testing.T) {
 	st := &SplitPaneState{Size: 299}
 	tt := ui.NewTester(func(c *ui.Context) {
 		Use(c, Settings{})
-		SplitPane(c, st, SplitPaneOptions{}, func() { ui.Text(c, "Files") }, func() { ui.Text(c, "Editor") }).Fill()
+		SplitPane(c, st, SplitPaneOptions{}, func() { ui.Text(c, "Files") }, func() { ui.Text(c, "Editor") }).Element.Fill()
 	}, 400, 200)
 	tt.SetSize(250, 200)
 	// 250 less the divider and the 40 DIP second minimum.
diff --git a/status_bar.go b/status_bar.go
index 8e9d1a2..4bec842 100644
--- a/status_bar.go
+++ b/status_bar.go
@@ -46,7 +46,7 @@ type StatusBarOptions struct {
 
 // StatusBarResult is a StatusBar and its event in this frame.
 type StatusBarResult struct {
-	*ui.Element
+	Element *ui.Element
 	// Clicked is the ID of the action item clicked, or empty.
 	Clicked string
 }
diff --git a/steps.go b/steps.go
index cae4dde..7ffbddb 100644
--- a/steps.go
+++ b/steps.go
@@ -29,15 +29,6 @@ type StepsOptions struct {
 	Label string
 }
 
-// StepsResult is the built Steps.
-type StepsResult struct {
-	*ui.Element
-	changed bool
-}
-
-// Changed reports that the user chose a clickable step in this frame.
-func (r StepsResult) Changed() bool { return r.changed }
-
 type stepsState int
 
 const (
@@ -48,7 +39,7 @@ const (
 )
 
 // Steps shows a process whose step *current is under way: earlier steps are done.
-func Steps(c *ui.Context, current *int, steps []Step, opts StepsOptions) StepsResult {
+func Steps(c *ui.Context, current *int, steps []Step, opts StepsOptions) ChoiceResult {
 	if len(steps) == 0 {
 		panic("mujica: Steps needs at least one step")
 	}
@@ -63,7 +54,7 @@ func Steps(c *ui.Context, current *int, steps []Step, opts StepsOptions) StepsRe
 	if opts.Label != "" {
 		root.Label(opts.Label)
 	}
-	res := StepsResult{Element: root}
+	res := ChoiceResult{Element: root}
 	root.Children(func() {
 		for i, s := range steps {
 			if s.Title == "" {
diff --git a/tabs.go b/tabs.go
index 36afb61..1b89d6d 100644
--- a/tabs.go
+++ b/tabs.go
@@ -27,17 +27,8 @@ type TabsOptions struct {
 	Label string
 }
 
-// TabsResult is the built Tabs: the element holding tabs and panel.
-type TabsResult struct {
-	*ui.Element
-	changed bool
-}
-
-// Changed reports a new choice made by the user in this frame.
-func (r TabsResult) Changed() bool { return r.changed }
-
 // Tabs shows tabs choosing *selected and the chosen tab's panel. Disabled tabs are skipped by the arrows.
-func Tabs(c *ui.Context, selected *int, tabs []Tab, opts TabsOptions) TabsResult {
+func Tabs(c *ui.Context, selected *int, tabs []Tab, opts TabsOptions) ChoiceResult {
 	if len(tabs) == 0 {
 		panic("mujica: Tabs needs at least one tab")
 	}
@@ -66,7 +57,7 @@ func Tabs(c *ui.Context, selected *int, tabs []Tab, opts TabsOptions) TabsResult
 	if opts.Vertical {
 		root.Row()
 	}
-	res := TabsResult{Element: root}
+	res := ChoiceResult{Element: root}
 	root.Children(func() {
 		var strip *ui.Element
 		if opts.Vertical {
diff --git a/tabs_test.go b/tabs_test.go
index 5148ea5..f6beb01 100644
--- a/tabs_test.go
+++ b/tabs_test.go
@@ -87,7 +87,7 @@ func TestTabsOverflowScrolls(t *testing.T) {
 	tt := ui.NewTester(func(c *ui.Context) {
 		Use(c, Settings{})
 		ui.Column(c).Width(240).Children(func() {
-			w = Tabs(c, &sel, tabs, TabsOptions{}).Bounds().W
+			w = Tabs(c, &sel, tabs, TabsOptions{}).Element.Bounds().W
 		})
 	}, 400, 200)
 	tt.Key(0, ui.KeyTab)
diff --git a/text_input.go b/text_input.go
index 961e082..4f5fecb 100644
--- a/text_input.go
+++ b/text_input.go
@@ -12,7 +12,7 @@ import (
 
 // InputResult is a value input's outer element and its events.
 type InputResult struct {
-	*ui.Element
+	Element *ui.Element
 	// Input is the text field inside, for focus and keys.
 	Input     *ui.Element
 	changed   bool
diff --git a/toggle_group.go b/toggle_group.go
index 246344e..e8617ec 100644
--- a/toggle_group.go
+++ b/toggle_group.go
@@ -12,7 +12,7 @@ import (
 
 // ChoiceResult is a choice control's element and whether its value changed this frame.
 type ChoiceResult struct {
-	*ui.Element
+	Element *ui.Element
 	changed bool
 }
 
diff --git a/transfer.go b/transfer.go
index 64771b2..4292457 100644
--- a/transfer.go
+++ b/transfer.go
@@ -29,22 +29,13 @@ type TransferOptions struct {
 	Disabled bool
 }
 
-// TransferParts are the parts of a Transfer.
-type TransferParts struct {
-	Element *ui.Element
-	changed bool
-}
-
-// Changed reports whether items moved this frame.
-func (p TransferParts) Changed() bool { return p.changed }
-
 type transferState struct {
 	checked map[string]bool
 	query   [2]string
 }
 
 // Transfer moves items between a source list and *target, the chosen IDs in order.
-func Transfer(c *ui.Context, target *[]string, items []TransferItem, opts TransferOptions) TransferParts {
+func Transfer(c *ui.Context, target *[]string, items []TransferItem, opts TransferOptions) ChoiceResult {
 	byID := make(map[string]TransferItem, len(items))
 	for _, it := range items {
 		if _, dup := byID[it.ID]; dup || it.ID == "" {
@@ -58,7 +49,7 @@ func Transfer(c *ui.Context, target *[]string, items []TransferItem, opts Transf
 		}
 	}
 	d := Density(c)
-	parts := TransferParts{}
+	parts := ChoiceResult{}
 	row := ui.Row(c).Gap(d.Unit() * 3).AlignItems(ui.Center).Disabled(opts.Disabled)
 	parts.Element = row
 	st := ui.Local(row, "transfer", func() transferState { return transferState{checked: map[string]bool{}} })
diff --git a/tree.go b/tree.go
index efd0c91..e7c745c 100644
--- a/tree.go
+++ b/tree.go
@@ -160,7 +160,7 @@ func (t *treeCore[K]) itemStatus(c *ui.Context, item K, status func(K) DataStatu
 
 // TreeView is a built Tree and what happened to it in this frame.
 type TreeView struct {
-	*ui.Element
+	Element                   *ui.Element
 	changed, submitted, retry bool
 }
 
@@ -185,7 +185,7 @@ func Tree[K comparable](c *ui.Context, s *TreeState[K], opts TreeOptions[K]) Tre
 	t.begin(opts.Label, &s.Selection, opts.Multiple)
 	var v TreeView
 	v.Element = ui.Column(c).MinHeight(0)
-	v.Children(func() {
+	v.Element.Children(func() {
 		if len(opts.Roots) == 0 {
 			t.clear(&s.Selection)
 			v.retry = dataPlaceholder(c, opts.Status, opts.Error, opts.Empty, msg(c, "list.empty"))
diff --git a/tree_table.go b/tree_table.go
index 41e4ba7..ddbb3f5 100644
--- a/tree_table.go
+++ b/tree_table.go
@@ -122,7 +122,7 @@ func TreeTable[K comparable](c *ui.Context, s *TreeTableState[K], opts TreeTable
 	before := s.Sort
 	var v DataTableView
 	v.Element = ui.Column(c).MinHeight(0).Gap(d.Unit() * 2)
-	v.Children(func() {
+	v.Element.Children(func() {
 		if len(opts.Roots) == 0 {
 			t.clear(&s.Selection)
 			v.retry = dataPlaceholder(c, opts.Status, opts.Error, opts.Empty, msg(c, "list.empty"))
diff --git a/tree_table_test.go b/tree_table_test.go
index 8a3c572..efacea2 100644
--- a/tree_table_test.go
+++ b/tree_table_test.go
@@ -50,7 +50,7 @@ func (h *ttHarness) view(c *ui.Context) {
 	h.c = c
 	ui.Column(c).Padding(10).Children(func() {
 		v := TreeTable(c, &h.st, h.opts)
-		v.Size(360, 320)
+		v.Element.Size(360, 320)
 		if v.SortChanged() {
 			h.sorts++
 		}
@@ -154,7 +154,7 @@ func TestTreeTableLargeIsVirtualized(t *testing.T) {
 		Use(c, Settings{})
 		clear(rows)
 		TreeTable(c, &st, TreeTableOptions[int]{Roots: roots, Children: kids, Label: strconv.Itoa,
-			Columns: []TreeColumn[int]{{ID: "n", Title: "N", Cell: cell(c), Compare: cmp.Compare[int]}, {ID: "m", Title: "M", Cell: cell(c)}}}).Size(320, 360)
+			Columns: []TreeColumn[int]{{ID: "n", Title: "N", Cell: cell(c), Compare: cmp.Compare[int]}, {ID: "m", Title: "M", Cell: cell(c)}}}).Element.Size(320, 360)
 	}
 	tt := ui.NewTester(view, 400, 400)
 	const bound = 26 // see TestTreeLargeIsVirtualized
@@ -187,7 +187,7 @@ func TestTreeTableSnapshot(t *testing.T) {
 		})
 		(*h).c = c
 		ui.Column(c).Padding(16).Children(func() {
-			TreeTable(c, &(*h).st, (*h).opts).Size(388, 208)
+			TreeTable(c, &(*h).st, (*h).opts).Element.Size(388, 208)
 		})
 	})
 }
@@ -208,7 +208,7 @@ func TestTreeTableSelectionFollowsLargeSort(t *testing.T) {
 				return nil
 			},
 			Columns: []TreeColumn[int]{{ID: "n", Title: "N", Cell: func(n int) { ui.Text(c, "#"+strconv.Itoa(n)) }, Compare: cmp.Compare[int]}},
-		}).Size(320, 360)
+		}).Element.Size(320, 360)
 	}
 	st.SetOpen(0, true)
 	tt := ui.NewTester(view, 400, 400)
diff --git a/tree_test.go b/tree_test.go
index e238b3a..02408e7 100644
--- a/tree_test.go
+++ b/tree_test.go
@@ -53,7 +53,7 @@ func (h *treeHarness) view(c *ui.Context) {
 	opts.Label = func(n string) string { h.built[n] = true; return label(n) }
 	ui.Column(c).Padding(10).Children(func() {
 		v := Tree(c, &h.st, opts)
-		v.Size(320, 360)
+		v.Element.Size(320, 360)
 		if v.Changed() {
 			h.changes++
 		}
@@ -186,7 +186,7 @@ func TestTreeLargeIsVirtualized(t *testing.T) {
 		Tree(c, &st, TreeOptions[int]{Roots: roots, Children: kids, Label: func(n int) string {
 			built++
 			return fmt.Sprintf("Node %d", n)
-		}}).Size(320, 360)
+		}}).Element.Size(320, 360)
 	}
 	tt := ui.NewTester(view, 400, 400)
 	// Two Label calls per row; a jump builds 2×(10 rows + 2 overscan) + 2 edges.
@@ -220,7 +220,7 @@ func TestTreeSnapshot(t *testing.T) {
 			return h
 		})
 		ui.Column(c).Padding(16).Children(func() {
-			Tree(c, &(*h).st, (*h).opts).Size(360, 228)
+			Tree(c, &(*h).st, (*h).opts).Element.Size(360, 228)
 		})
 	})
 }
@@ -234,7 +234,7 @@ func TestTreeSelectionFollowsLargeReorder(t *testing.T) {
 	view := func(c *ui.Context) {
 		Use(c, Settings{Mode: Light})
 		Tree(c, &st, TreeOptions[int]{Roots: roots, Children: func(int) []int { return nil },
-			Label: func(n int) string { return fmt.Sprintf("Node %d", n) }}).Size(320, 360)
+			Label: func(n int) string { return fmt.Sprintf("Node %d", n) }}).Element.Size(320, 360)
 	}
 	tt := ui.NewTester(view, 400, 400)
 	if err := tt.Click("Node 2"); err != nil {