diff --git a/widget/bool.go b/widget/bool.go
index fde8c323..5afaece4 100644
--- a/widget/bool.go
+++ b/widget/bool.go
@@ -7,17 +7,24 @@ import (
 
 type Bool struct {
 	Value bool
-
 	// Last is the last registered click.
 	Last Click
 
+	// changeVal tracks Value from the most recent call to Changed.
+	changeVal bool
+
 	gesture gesture.Click
 }
 
-// Update the checked state according to incoming events,
-// and reports whether Value changed.
-func (b *Bool) Update(gtx layout.Context) bool {
-	was := b.Value
+// Changed reports whether Value has changed since the last
+// call to Changed.
+func (b *Bool) Changed() bool {
+	changed := b.Value != b.changeVal
+	b.changeVal = b.Value
+	return changed
+}
+
+func (b *Bool) Layout(gtx layout.Context) {
 	for _, e := range b.gesture.Events(gtx) {
 		switch e.Type {
 		case gesture.TypeClick:
@@ -28,9 +35,5 @@ func (b *Bool) Update(gtx layout.Context) bool {
 			b.Value = !b.Value
 		}
 	}
-	return b.Value != was
-}
-
-func (b *Bool) Layout(gtx layout.Context) {
 	b.gesture.Add(gtx.Ops)
 }
diff --git a/widget/button.go b/widget/button.go
index 2f4b73f9..85c4a130 100644
--- a/widget/button.go
+++ b/widget/button.go
@@ -27,31 +27,24 @@ type Click struct {
 	Time     time.Time
 }
 
-// Clicked calls Update and reports whether the button was
-// clicked since the last call. Multiple clicks result in Clicked
-// returning true once per click.
-func (b *Clickable) Clicked(gtx layout.Context) bool {
-	b.Update(gtx)
+// Clicked and reports whether the button was clicked since the last
+// call to Clicked. Clicked returns true once per click.
+func (b *Clickable) Clicked() bool {
 	if b.clicks > 0 {
 		b.clicks--
-		if b.clicks > 0 {
-			// Ensure timely delivery of remaining clicks.
-			op.InvalidateOp{}.Add(gtx.Ops)
-		}
 		return true
 	}
 	return false
 }
 
-// History is the past clicks useful for drawing click markers.
-// Clicks are retained for a short duration (about a second).
+// History is the past pointer presses useful for drawing markers.
+// History is retained for a short duration (about a second).
 func (b *Clickable) History() []Click {
 	return b.history
 }
 
 func (b *Clickable) Layout(gtx layout.Context) layout.Dimensions {
-	// Flush clicks from before the previous frame.
-	b.Update(gtx)
+	b.update(gtx)
 	var st op.StackOp
 	st.Push(gtx.Ops)
 	pointer.Rect(image.Rectangle{Max: gtx.Constraints.Min}).Add(gtx.Ops)
@@ -68,11 +61,9 @@ func (b *Clickable) Layout(gtx layout.Context) layout.Dimensions {
 	return layout.Dimensions{Size: gtx.Constraints.Min}
 }
 
-// Update the button state by processing events. The underlying
-// gesture events are returned for use beyond what Clicked offers.
-func (b *Clickable) Update(gtx layout.Context) []gesture.ClickEvent {
-	evts := b.click.Events(gtx)
-	for _, e := range evts {
+// update the button state by processing events.
+func (b *Clickable) update(gtx layout.Context) {
+	for _, e := range b.click.Events(gtx) {
 		switch e.Type {
 		case gesture.TypeClick:
 			b.clicks++
@@ -83,5 +74,4 @@ func (b *Clickable) Update(gtx layout.Context) []gesture.ClickEvent {
 			})
 		}
 	}
-	return evts
 }
diff --git a/widget/editor.go b/widget/editor.go
index 01b5ddd7..b3fe246a 100644
--- a/widget/editor.go
+++ b/widget/editor.go
@@ -89,8 +89,7 @@ const (
 )
 
 // Events returns available editor events.
-func (e *Editor) Events(gtx layout.Context) []EditorEvent {
-	e.processEvents(gtx)
+func (e *Editor) Events() []EditorEvent {
 	events := e.events
 	e.events = nil
 	e.prevEvents = 0
diff --git a/widget/enum.go b/widget/enum.go
index 7b38931d..f2d1199e 100644
--- a/widget/enum.go
+++ b/widget/enum.go
@@ -8,6 +8,8 @@ import (
 type Enum struct {
 	Value string
 
+	changeVal string
+
 	clicks []gesture.Click
 	values []string
 }
@@ -21,19 +23,12 @@ func index(vs []string, t string) int {
 	return -1
 }
 
-// Update the Value according to incoming events, and
-// reports whether Value changed.
-func (e *Enum) Update(gtx layout.Context) bool {
-	was := e.Value
-	for i := range e.clicks {
-		for _, ev := range e.clicks[i].Events(gtx) {
-			switch ev.Type {
-			case gesture.TypeClick:
-				e.Value = e.values[i]
-			}
-		}
-	}
-	return e.Value != was
+// Changed reports whether Value has changed since the last
+// call to Changed.
+func (e *Enum) Changed() bool {
+	changed := e.changeVal != e.Value
+	e.changeVal = e.Value
+	return changed
 }
 
 // Layout adds the event handler for key.
@@ -44,6 +39,13 @@ func (e *Enum) Layout(gtx layout.Context, key string) {
 		e.clicks[len(e.clicks)-1].Add(gtx.Ops)
 	} else {
 		idx := index(e.values, key)
-		e.clicks[idx].Add(gtx.Ops)
+		clk := &e.clicks[idx]
+		for _, ev := range clk.Events(gtx) {
+			switch ev.Type {
+			case gesture.TypeClick:
+				e.Value = e.values[idx]
+			}
+		}
+		clk.Add(gtx.Ops)
 	}
 }
diff --git a/widget/material/checkbox.go b/widget/material/checkbox.go
index 25b45614..f52456c0 100644
--- a/widget/material/checkbox.go
+++ b/widget/material/checkbox.go
@@ -31,7 +31,6 @@ func CheckBox(th *Theme, checkBox *widget.Bool, label string) CheckBoxStyle {
 
 // Layout updates the checkBox and displays it.
 func (c CheckBoxStyle) Layout(gtx layout.Context) layout.Dimensions {
-	c.CheckBox.Update(gtx)
 	dims := c.layout(gtx, c.CheckBox.Value)
 	c.CheckBox.Layout(gtx)
 	return dims
diff --git a/widget/material/radiobutton.go b/widget/material/radiobutton.go
index 58d95881..4b14b06e 100644
--- a/widget/material/radiobutton.go
+++ b/widget/material/radiobutton.go
@@ -36,7 +36,6 @@ func RadioButton(th *Theme, group *widget.Enum, key, label string) RadioButtonSt
 
 // Layout updates enum and displays the radio button.
 func (r RadioButtonStyle) Layout(gtx layout.Context) layout.Dimensions {
-	r.Group.Update(gtx)
 	dims := r.layout(gtx, r.Group.Value == r.Key)
 	r.Group.Layout(gtx, r.Key)
 	return dims
diff --git a/widget/material/switch.go b/widget/material/switch.go
index 04ab3369..23425a06 100644
--- a/widget/material/switch.go
+++ b/widget/material/switch.go
@@ -30,8 +30,6 @@ func Switch(th *Theme, swtch *widget.Bool) SwitchStyle {
 
 // Layout updates the checkBox and displays it.
 func (s SwitchStyle) Layout(gtx layout.Context) layout.Dimensions {
-	s.Switch.Update(gtx)
-
 	trackWidth := gtx.Px(unit.Dp(36))
 	trackHeight := gtx.Px(unit.Dp(16))
 	thumbSize := gtx.Px(unit.Dp(20))