app: update TopMost comment

TopMost is also supported on Windows.

Signed-off-by: qiannian <qianniancn@gmail.com>

app/internal/windows/windows.go

@@ -207,7 +207,9 @@ const (
 	CFS_POINT        = 0x0002
 	CFS_CANDIDATEPOS = 0x0040
 
-	HWND_TOPMOST = ^(uint32(1) - 1) // -1
+	HWND_TOP       = syscall.Handle(0)
+	HWND_TOPMOST   = ^(syscall.Handle(1) - 1) // -1
+	HWND_NOTOPMOST = ^(syscall.Handle(2) - 1) // -2
 
 	HTCAPTION     = 2
 	HTCLIENT      = 1
@@ -782,7 +784,7 @@ func SetWindowPlacement(hwnd syscall.Handle, wp *WindowPlacement) {
 	_SetWindowPlacement.Call(uintptr(hwnd), uintptr(unsafe.Pointer(wp)))
 }
 
-func SetWindowPos(hwnd syscall.Handle, hwndInsertAfter uint32, x, y, dx, dy int32, style uintptr) {
+func SetWindowPos(hwnd, hwndInsertAfter syscall.Handle, x, y, dx, dy int32, style uintptr) {
 	_SetWindowPos.Call(uintptr(hwnd), uintptr(hwndInsertAfter),
 		uintptr(x), uintptr(y),
 		uintptr(dx), uintptr(dy),

app/os_windows.go

@@ -369,8 +369,7 @@ func windowProc(hwnd syscall.Handle, msg uint32, wParam, lParam uintptr) uintptr
 		w.update()
 	case windows.WM_WINDOWPOSCHANGED:
 		w.update()
-	case windows.WM_SIZE:
-		w.update()
+		return 0
 	case windows.WM_GETMINMAXINFO:
 		mm := (*windows.MinMaxInfo)(unsafe.Pointer(lParam))
 
@@ -413,6 +412,7 @@ func windowProc(hwnd syscall.Handle, msg uint32, wParam, lParam uintptr) uintptr
 		icaret := image.Pt(int(caret.X+.5), int(caret.Y+.5))
 		windows.ImmSetCompositionWindow(imc, icaret.X, icaret.Y)
 		windows.ImmSetCandidateWindow(imc, icaret.X, icaret.Y)
+		return windows.TRUE
 	case windows.WM_IME_COMPOSITION:
 		imc := windows.ImmGetContext(w.hwnd)
 		if imc == 0 {
@@ -495,34 +495,32 @@ func getModifiers() key.Modifiers {
 // hitTest returns the non-client area hit by the point, needed to
 // process WM_NCHITTEST.
 func (w *window) hitTest(x, y int) uintptr {
-	if w.config.Mode != Windowed {
-		// Only windowed mode should allow resizing.
-		return windows.HTCLIENT
-	}
-	// Check for resize handle before system actions; otherwise it can be impossible to
-	// resize a custom-decorations window when the system move area is flush with the
-	// edge of the window.
-	top := y <= w.borderSize.Y
-	bottom := y >= w.config.Size.Y-w.borderSize.Y
-	left := x <= w.borderSize.X
-	right := x >= w.config.Size.X-w.borderSize.X
-	switch {
-	case top && left:
-		return windows.HTTOPLEFT
-	case top && right:
-		return windows.HTTOPRIGHT
-	case bottom && left:
-		return windows.HTBOTTOMLEFT
-	case bottom && right:
-		return windows.HTBOTTOMRIGHT
-	case top:
-		return windows.HTTOP
-	case bottom:
-		return windows.HTBOTTOM
-	case left:
-		return windows.HTLEFT
-	case right:
-		return windows.HTRIGHT
+	if w.config.Mode == Windowed {
+		// Check for resize handle before system actions; otherwise it can be impossible to
+		// resize a custom-decorations window when the system move area is flush with the
+		// edge of the window.
+		top := y <= w.borderSize.Y
+		bottom := y >= w.config.Size.Y-w.borderSize.Y
+		left := x <= w.borderSize.X
+		right := x >= w.config.Size.X-w.borderSize.X
+		switch {
+		case top && left:
+			return windows.HTTOPLEFT
+		case top && right:
+			return windows.HTTOPRIGHT
+		case bottom && left:
+			return windows.HTBOTTOMLEFT
+		case bottom && right:
+			return windows.HTBOTTOMRIGHT
+		case top:
+			return windows.HTTOP
+		case bottom:
+			return windows.HTBOTTOM
+		case left:
+			return windows.HTLEFT
+		case right:
+			return windows.HTRIGHT
+		}
 	}
 	p := f32.Pt(float32(x), float32(y))
 	if a, ok := w.w.ActionAt(p); ok && a == system.ActionMove {
@@ -701,7 +699,13 @@ func (w *window) ReadClipboard() {
 	w.readClipboard()
 }
 
-func (w *window) readClipboard() error {
+func (w *window) readClipboard() (cerr error) {
+	defer func() {
+		if cerr != nil {
+			w.processDataEvent("")
+		}
+	}()
+
 	if err := windows.OpenClipboard(w.hwnd); err != nil {
 		return err
 	}
@@ -716,13 +720,17 @@ func (w *window) readClipboard() error {
 	}
 	defer windows.GlobalUnlock(mem)
 	content := gowindows.UTF16PtrToString((*uint16)(unsafe.Pointer(ptr)))
+	w.processDataEvent(content)
+	return nil
+}
+
+func (w *window) processDataEvent(content string) {
 	w.ProcessEvent(transfer.DataEvent{
 		Type: "application/text",
 		Open: func() io.ReadCloser {
 			return io.NopCloser(strings.NewReader(content))
 		},
 	})
-	return nil
 }
 
 func (w *window) Configure(options []Option) {
@@ -739,7 +747,16 @@ func (w *window) Configure(options []Option) {
 	style := windows.GetWindowLong(w.hwnd, windows.GWL_STYLE)
 	var showMode int32
 	var x, y, width, height int32
-	swpStyle := uintptr(windows.SWP_NOZORDER | windows.SWP_FRAMECHANGED)
+	swpStyle := uintptr(windows.SWP_FRAMECHANGED)
+	if cnf.TopMost == w.config.TopMost {
+		// Don't change the z-order if TopMost didn't change.
+		swpStyle |= windows.SWP_NOZORDER
+	}
+	hwndAfter := windows.HWND_NOTOPMOST
+	if cnf.TopMost {
+		hwndAfter = windows.HWND_TOPMOST
+	}
+	w.config.TopMost = cnf.TopMost
 	winStyle := uintptr(windows.WS_OVERLAPPEDWINDOW)
 	style &^= winStyle
 	switch cnf.Mode {
@@ -791,7 +808,7 @@ func (w *window) Configure(options []Option) {
 
 	// Note: these invocation all trigger the windows callback method which may process a pending system.ActionCenter
 	// action, so SetWindowPos should come first so as to not "overwrite" system.ActionCenter.
-	windows.SetWindowPos(w.hwnd, 0, x, y, width, height, swpStyle)
+	windows.SetWindowPos(w.hwnd, hwndAfter, x, y, width, height, swpStyle)
 	windows.SetWindowLong(w.hwnd, windows.GWL_STYLE, style)
 	windows.ShowWindow(w.hwnd, showMode)
 }
@@ -912,19 +929,15 @@ func (w *window) Perform(acts system.Action) {
 			y := (mi.Bottom - mi.Top - dy) / 2
 			windows.SetWindowPos(w.hwnd, 0, x, y, dx, dy, windows.SWP_NOZORDER|windows.SWP_FRAMECHANGED)
 		case system.ActionRaise:
-			w.raise()
+			windows.SetForegroundWindow(w.hwnd)
+			windows.SetWindowPos(w.hwnd, windows.HWND_TOP, 0, 0, 0, 0,
+				windows.SWP_NOMOVE|windows.SWP_NOSIZE|windows.SWP_SHOWWINDOW)
 		case system.ActionClose:
 			windows.PostMessage(w.hwnd, windows.WM_CLOSE, 0, 0)
 		}
 	})
 }
 
-func (w *window) raise() {
-	windows.SetForegroundWindow(w.hwnd)
-	windows.SetWindowPos(w.hwnd, windows.HWND_TOPMOST, 0, 0, 0, 0,
-		windows.SWP_NOMOVE|windows.SWP_NOSIZE|windows.SWP_SHOWWINDOW)
-}
-
 func convertKeyCode(code uintptr) (key.Name, bool) {
 	if '0' <= code && code <= '9' || 'A' <= code && code <= 'Z' {
 		return key.Name(rune(code)), true

app/window.go

@@ -439,6 +439,7 @@ func (c *callbacks) EditorState() editorState {
 
 func (c *callbacks) SetComposingRegion(r key.Range) {
 	c.w.imeState.compose = r
+	c.w.driver.ProcessEvent(key.CompositionEvent(r))
 }
 
 func (c *callbacks) EditorInsert(text string) {
@@ -971,7 +972,7 @@ func Decorated(enabled bool) Option {
 
 // TopMost windows will be rendered above all other non-top-most windows.
 //
-// TopMost windows are only supported on MacOS currently.
+// TopMost windows are supported on macOS, Windows.
 func TopMost(enabled bool) Option {
 	return func(_ unit.Metric, cnf *Config) {
 		cnf.TopMost = enabled

font/opentype/opentype.go

@@ -106,7 +106,7 @@ func parseLoader(ld *opentype.Loader) (*fontapi.Font, giofont.Font, error) {
 // Face many be invoked any number of times and is safe so long as each return value is
 // only used by one goroutine.
 func (f Face) Face() *fontapi.Face {
-	return &fontapi.Face{Font: f.face}
+	return fontapi.NewFace(f.face)
 }
 
 // FontFace returns a text.Font with populated font metadata for the

go.mod

@@ -5,7 +5,7 @@ go 1.24.0
 require (
 	eliasnaur.com/font v0.0.0-20230308162249-dd43949cb42d
 	gioui.org/shader v1.0.8
-	github.com/go-text/typesetting v0.3.0
+	github.com/go-text/typesetting v0.3.4
 	golang.org/x/exp v0.0.0-20250408133849-7e4ce0ab07d0
 	golang.org/x/exp/shiny v0.0.0-20250408133849-7e4ce0ab07d0
 	golang.org/x/image v0.26.0

go.sum

@@ -3,10 +3,10 @@ eliasnaur.com/font v0.0.0-20230308162249-dd43949cb42d/go.mod h1:OYVuxibdk9OSLX8v
 gioui.org/cpu v0.0.0-20210808092351-bfe733dd3334/go.mod h1:A8M0Cn5o+vY5LTMlnRoK3O5kG+rH0kWfJjeKd9QpBmQ=
 gioui.org/shader v1.0.8 h1:6ks0o/A+b0ne7RzEqRZK5f4Gboz2CfG+mVliciy6+qA=
 gioui.org/shader v1.0.8/go.mod h1:mWdiME581d/kV7/iEhLmUgUK5iZ09XR5XpduXzbePVM=
-github.com/go-text/typesetting v0.3.0 h1:OWCgYpp8njoxSRpwrdd1bQOxdjOXDj9Rqart9ML4iF4=
-github.com/go-text/typesetting v0.3.0/go.mod h1:qjZLkhRgOEYMhU9eHBr3AR4sfnGJvOXNLt8yRAySFuY=
-github.com/go-text/typesetting-utils v0.0.0-20241103174707-87a29e9e6066 h1:qCuYC+94v2xrb1PoS4NIDe7DGYtLnU2wWiQe9a1B1c0=
-github.com/go-text/typesetting-utils v0.0.0-20241103174707-87a29e9e6066/go.mod h1:DDxDdQEnB70R8owOx3LVpEFvpMK9eeH1o2r0yZhFI9o=
+github.com/go-text/typesetting v0.3.4 h1:YYurUOtEb9kGSOz4uE3k4OpBGsp1dDL8+fjCeaFamAU=
+github.com/go-text/typesetting v0.3.4/go.mod h1:4qZCQphq4KSgGTAeI0uMEkVbROgfah8BuyF5LRYr7XY=
+github.com/go-text/typesetting-utils v0.0.0-20260223113751-2d88ac90dae3 h1:drBZzMgdYPbmyXqOto4YhhJGrFIQCX94FpR4MzTCsos=
+github.com/go-text/typesetting-utils v0.0.0-20260223113751-2d88ac90dae3/go.mod h1:3/62I4La/HBRX9TcTpBj4eipLiwzf+vhI+7whTc9V7o=
 golang.org/x/exp v0.0.0-20250408133849-7e4ce0ab07d0 h1:R84qjqJb5nVJMxqWYb3np9L5ZsaDtB+a39EqjV0JSUM=
 golang.org/x/exp v0.0.0-20250408133849-7e4ce0ab07d0/go.mod h1:S9Xr4PYopiDyqSyp5NjCrhFrqg6A5zA2E/iPHPhqnS8=
 golang.org/x/exp/shiny v0.0.0-20250408133849-7e4ce0ab07d0 h1:tMSqXTK+AQdW3LpCbfatHSRPHeW6+2WuxaVQuHftn80=

internal/egl/egl_windows.go

@@ -41,14 +41,10 @@ var (
 	_eglWaitClient          *syscall.Proc
 )
 
-var loadOnce sync.Once
+var loadOnce = sync.OnceValue(loadDLLs)
 
 func loadEGL() error {
-	var err error
-	loadOnce.Do(func() {
-		err = loadDLLs()
-	})
-	return err
+	return loadOnce()
 }
 
 func loadDLLs() error {

io/input/pointer.go

@@ -760,6 +760,8 @@ func (q *pointerQueue) Push(handlers map[event.Tag]*handler, state pointerState,
 		if p.pressed {
 			p, evts = q.deliverDragEvent(handlers, p, evts)
 		}
+	case pointer.Leave:
+		p, evts, state.cursor, _ = q.deliverEnterLeaveEvents(handlers, state.cursor, p, evts, e)
 	case pointer.Release:
 		evts = q.deliverEvent(handlers, p, evts, e)
 		p.pressed = false
@@ -823,7 +825,7 @@ func (q *pointerQueue) deliverEvent(handlers map[event.Tag]*handler, p pointerIn
 func (q *pointerQueue) deliverEnterLeaveEvents(handlers map[event.Tag]*handler, cursor pointer.Cursor, p pointerInfo, evts []taggedEvent, e pointer.Event) (pointerInfo, []taggedEvent, pointer.Cursor, bool) {
 	changed := false
 	var hits []event.Tag
-	if e.Source != pointer.Mouse && !p.pressed && e.Kind != pointer.Press {
+	if e.Kind == pointer.Leave || e.Source != pointer.Mouse && !p.pressed && e.Kind != pointer.Press {
 		// Consider non-mouse pointers leaving when they're released.
 	} else {
 		var transSrc *pointerFilter

io/input/pointer_test.go

@@ -255,6 +255,45 @@ func TestPointerMove(t *testing.T) {
 	assertEventPointerTypeSequence(t, events(&r, -1, filter(handler2)), pointer.Enter, pointer.Move, pointer.Leave, pointer.Cancel)
 }
 
+func TestPointerLeave(t *testing.T) {
+	handler := new(int)
+	var ops op.Ops
+
+	filter := pointer.Filter{
+		Target: handler,
+		Kinds:  pointer.Move | pointer.Enter | pointer.Leave | pointer.Cancel,
+	}
+	defer clip.Rect(image.Rect(0, 0, 100, 100)).Push(&ops).Pop()
+	event.Op(&ops, handler)
+
+	var r Router
+	events(&r, -1, filter)
+	r.Frame(&ops)
+	r.Queue(
+		pointer.Event{
+			Kind:      pointer.Move,
+			Source:    pointer.Mouse,
+			PointerID: 1,
+			Position:  f32.Pt(50, 50),
+		},
+		pointer.Event{
+			Kind:      pointer.Leave,
+			Source:    pointer.Mouse,
+			PointerID: 1,
+			Position:  f32.Pt(50, 50),
+		},
+	)
+	assertEventPointerTypeSequence(t, events(&r, -1, filter), pointer.Enter, pointer.Move, pointer.Leave)
+
+	r.Queue(pointer.Event{
+		Kind:      pointer.Move,
+		Source:    pointer.Mouse,
+		PointerID: 1,
+		Position:  f32.Pt(50, 50),
+	})
+	assertEventPointerTypeSequence(t, events(&r, -1, filter), pointer.Enter, pointer.Move)
+}
+
 func TestPointerTypes(t *testing.T) {
 	handler := new(int)
 	var ops op.Ops

io/input/router.go

@@ -419,7 +419,7 @@ func (f *filter) Merge(f2 filter) {
 
 func (f *filter) Matches(e event.Event) bool {
 	switch e.(type) {
-	case key.FocusEvent, key.SnippetEvent, key.EditEvent, key.SelectionEvent:
+	case key.FocusEvent, key.SnippetEvent, key.EditEvent, key.SelectionEvent, key.CompositionEvent:
 		return f.focusable
 	default:
 		return f.pointer.Matches(e)
@@ -463,6 +463,13 @@ func (q *Router) processEvent(e event.Event, system bool) {
 			evts = append(evts, taggedEvent{tag: f, event: e})
 		}
 		q.changeState(e, state, evts)
+	case key.CompositionEvent:
+		e = key.CompositionEvent(rangeNorm(key.Range(e)))
+		var evts []taggedEvent
+		if f := state.focus; f != nil {
+			evts = append(evts, taggedEvent{tag: f, event: e})
+		}
+		q.changeState(e, state, evts)
 	case key.EditEvent, key.FocusEvent, key.SelectionEvent:
 		var evts []taggedEvent
 		if f := state.focus; f != nil {

io/key/key.go

@@ -77,6 +77,9 @@ type Caret struct {
 // SelectionEvent is generated when an input method changes the selection.
 type SelectionEvent Range
 
+// CompositionEvent is generated when an input method changes the composing range.
+type CompositionEvent Range
+
 // SnippetEvent is generated when the snippet range is updated by an
 // input method.
 type SnippetEvent Range
@@ -243,11 +246,12 @@ func (h InputHintOp) Add(o *op.Ops) {
 	data[1] = byte(h.Hint)
 }
 
-func (EditEvent) ImplementsEvent()      {}
-func (Event) ImplementsEvent()          {}
-func (FocusEvent) ImplementsEvent()     {}
-func (SnippetEvent) ImplementsEvent()   {}
-func (SelectionEvent) ImplementsEvent() {}
+func (EditEvent) ImplementsEvent()        {}
+func (Event) ImplementsEvent()            {}
+func (FocusEvent) ImplementsEvent()       {}
+func (CompositionEvent) ImplementsEvent() {}
+func (SnippetEvent) ImplementsEvent()     {}
+func (SelectionEvent) ImplementsEvent()   {}
 
 func (FocusCmd) ImplementsCommand()        {}
 func (SoftKeyboardCmd) ImplementsCommand() {}

text/gotext.go

@@ -103,8 +103,7 @@ func (l *line) insertTrailingSyntheticNewline(newLineClusterIdx int) {
 		clusterIndex: newLineClusterIdx,
 		glyphCount:   0,
 		runeCount:    1,
-		xAdvance:     0,
-		yAdvance:     0,
+		advance:      0,
 		xOffset:      0,
 		yOffset:      0,
 	}
@@ -160,9 +159,9 @@ type glyph struct {
 	// runeCount is the quantity of runes in the source text that this glyph
 	// corresponds to.
 	runeCount int
-	// xAdvance and yAdvance describe the distance the dot moves when
-	// laying out the glyph on the X or Y axis.
-	xAdvance, yAdvance fixed.Int26_6
+	// advance is the distance the dot moves when laying out the glyph along
+	// the run's primary axis.
+	advance fixed.Int26_6
 	// xOffset and yOffset describe offsets from the dot that should be
 	// applied when rendering the glyph.
 	xOffset, yOffset fixed.Int26_6
@@ -270,8 +269,9 @@ func newShaperImpl(systemFonts bool, collection []FontFace) *shaperImpl {
 // in the order in which they are loaded, with the first face being the default.
 func (s *shaperImpl) Load(f FontFace) {
 	desc := opentype.FontToDescription(f.Font)
-	s.fontMap.AddFace(f.Face.Face(), fontscan.Location{File: fmt.Sprint(desc)}, desc)
-	s.addFace(f.Face.Face(), f.Font)
+	face := f.Face.Face()
+	s.fontMap.AddFace(face, fontscan.Location{File: fmt.Sprint(desc)}, desc)
+	s.addFace(face, f.Font)
 }
 
 func (s *shaperImpl) addFace(f *font.Face, md giofont.Font) {
@@ -437,8 +437,7 @@ func (s *shaperImpl) shapeText(ppem fixed.Int26_6, lc system.Locale, txt []rune)
 						Height:       input.Size,
 						XBearing:     0,
 						YBearing:     0,
-						XAdvance:     input.Size,
-						YAdvance:     input.Size,
+						Advance:      input.Size,
 						XOffset:      0,
 						YOffset:      0,
 						ClusterIndex: input.RunStart,
@@ -854,11 +853,10 @@ func toGioGlyphs(in []shaping.Glyph, ppem fixed.Int26_6, faceIdx int) []glyph {
 		bounds.Max = bounds.Min.Add(fixed.Point26_6{X: g.Width, Y: -g.Height})
 		out = append(out, glyph{
 			id:           newGlyphID(ppem, faceIdx, g.GlyphID),
-			clusterIndex: g.ClusterIndex,
-			runeCount:    g.RuneCount,
-			glyphCount:   g.GlyphCount,
-			xAdvance:     g.XAdvance,
-			yAdvance:     g.YAdvance,
+			clusterIndex: g.TextIndex(),
+			runeCount:    g.RunesCount(),
+			glyphCount:   g.GlyphsCount(),
+			advance:      g.Advance,
 			xOffset:      g.XOffset,
 			yOffset:      g.YOffset,
 			bounds:       bounds,

text/shaper.go

@@ -464,7 +464,7 @@ func (l *Shaper) NextGlyph() (_ Glyph, ok bool) {
 		if rtl {
 			// Modify the advance prior to computing runOffset to ensure that the
 			// current glyph's width is subtracted in RTL.
-			l.advance += g.xAdvance
+			l.advance += g.advance
 		}
 		// runOffset computes how far into the run the dot should be positioned.
 		runOffset := l.advance
@@ -477,7 +477,7 @@ func (l *Shaper) NextGlyph() (_ Glyph, ok bool) {
 			Y:       int32(line.yOffset),
 			Ascent:  line.ascent,
 			Descent: line.descent,
-			Advance: g.xAdvance,
+			Advance: g.advance,
 			Runes:   uint16(g.runeCount),
 			Offset: fixed.Point26_6{
 				X: g.xOffset,
@@ -490,7 +490,7 @@ func (l *Shaper) NextGlyph() (_ Glyph, ok bool) {
 		}
 		l.glyph++
 		if !rtl {
-			l.advance += g.xAdvance
+			l.advance += g.advance
 		}
 
 		endOfRun := l.glyph == len(run.Glyphs)

text/shaper_test.go

@@ -450,8 +450,8 @@ func printLinePositioning(t *testing.T, lines []line, glyphs []Glyph) {
 			for g := start; ; g += inc {
 				glyph := run.Glyphs[g]
 				if glyphCursor < len(glyphs) {
-					t.Logf("glyph %2d, adv %3d, runes %2d, glyphs %d - glyphs[%2d] flags %s", g, glyph.xAdvance, glyph.runeCount, glyph.glyphCount, glyphCursor, glyphs[glyphCursor].Flags)
-					t.Logf("glyph %2d, adv %3d, runes %2d, glyphs %d - n/a", g, glyph.xAdvance, glyph.runeCount, glyph.glyphCount)
+					t.Logf("glyph %2d, adv %3d, runes %2d, glyphs %d - glyphs[%2d] flags %s", g, glyph.advance, glyph.runeCount, glyph.glyphCount, glyphCursor, glyphs[glyphCursor].Flags)
+					t.Logf("glyph %2d, adv %3d, runes %2d, glyphs %d - n/a", g, glyph.advance, glyph.runeCount, glyph.glyphCount)
 				}
 				glyphCursor++
 				if g == end {

widget/editor.go

@@ -25,6 +25,7 @@ import (
 	"gioui.org/layout"
 	"gioui.org/op"
 	"gioui.org/op/clip"
+	"gioui.org/op/paint"
 	"gioui.org/text"
 	"gioui.org/unit"
 )
@@ -107,8 +108,9 @@ type imeState struct {
 		rng   key.Range
 		caret key.Caret
 	}
-	snippet    key.Snippet
-	start, end int
+	snippet     key.Snippet
+	composition key.Range
+	start, end  int
 }
 
 type maskReader struct {
@@ -398,9 +400,12 @@ func (e *Editor) processKey(gtx layout.Context) (EditorEvent, bool) {
 		case key.FocusEvent:
 			// Reset IME state.
 			e.ime.imeState = imeState{}
+			e.ime.composition = key.Range{Start: -1, End: -1}
 			if ke.Focus && !e.ReadOnly {
 				gtx.Execute(key.SoftKeyboardCmd{Show: true})
 			}
+		case key.CompositionEvent:
+			e.ime.composition = key.Range(ke)
 		case key.Event:
 			if !gtx.Focused(e) || ke.State != key.Press {
 				break
@@ -735,6 +740,7 @@ func (e *Editor) layout(gtx layout.Context, textMaterial, selectMaterial op.Call
 	if e.Len() > 0 {
 		e.paintSelection(gtx, selectMaterial)
 		e.paintText(gtx, textMaterial)
+		e.paintComposition(gtx, textMaterial)
 	}
 	if gtx.Enabled() {
 		e.paintCaret(gtx, textMaterial)
@@ -759,6 +765,28 @@ func (e *Editor) paintText(gtx layout.Context, material op.CallOp) {
 	e.text.PaintText(gtx, material)
 }
 
+func (e *Editor) paintComposition(gtx layout.Context, material op.CallOp) {
+	e.initBuffer()
+	r := e.ime.composition
+	if r.Start == -1 || r.Start == r.End {
+		return
+	}
+	e.text.regions = e.text.Regions(r.Start, r.End, e.text.regions)
+	thickness := max(gtx.Dp(unit.Dp(1)), 1)
+	for _, region := range e.text.regions {
+		y := region.Bounds.Max.Y - max(region.Baseline/3, thickness)
+		underline := image.Rect(region.Bounds.Min.X, y, region.Bounds.Max.X, y+thickness)
+		underline = underline.Intersect(image.Rectangle{Max: e.text.viewSize})
+		if underline.Empty() {
+			continue
+		}
+		stack := clip.Rect(underline).Push(gtx.Ops)
+		material.Add(gtx.Ops)
+		paint.PaintOp{}.Add(gtx.Ops)
+		stack.Pop()
+	}
+}
+
 // paintCaret paints the text glyphs using the provided material to set the fill material
 // of the caret rectangle.
 func (e *Editor) paintCaret(gtx layout.Context, material op.CallOp) {

widget/material/decorations.go

@@ -5,7 +5,6 @@ import (
 	"image/color"
 
 	"gioui.org/f32"
-	"gioui.org/io/semantic"
 	"gioui.org/io/system"
 	"gioui.org/layout"
 	"gioui.org/op"
@@ -86,21 +85,10 @@ func (d DecorationsStyle) layoutDecorations(gtx layout.Context) layout.Dimension
 					continue
 				}
 				cl := d.Decorations.Clickable(a)
-				dims := cl.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
-					semantic.Button.Add(gtx.Ops)
-					return layout.Background{}.Layout(gtx,
-						func(gtx layout.Context) layout.Dimensions {
-							defer clip.Rect{Max: gtx.Constraints.Min}.Push(gtx.Ops).Pop()
-							for _, c := range cl.History() {
-								drawInk(gtx, c)
-							}
-							return layout.Dimensions{Size: gtx.Constraints.Min}
-						},
-						func(gtx layout.Context) layout.Dimensions {
-							paint.ColorOp{Color: d.Foreground}.Add(gtx.Ops)
-							return inset.Layout(gtx, w)
-						},
-					)
+				dims := Clickable(gtx, cl, func(gtx layout.Context) layout.Dimensions {
+					system.ActionInputOp(a).Add(gtx.Ops)
+					paint.ColorOp{Color: d.Foreground}.Add(gtx.Ops)
+					return inset.Layout(gtx, w)
 				})
 				size.X += dims.Size.X
 				if size.Y < dims.Size.Y {