From 0715c801e236eb4826942b661ee10504a206f2e6 Mon Sep 17 00:00:00 2001
From: Elias Naur <mail@eliasnaur.com>
Date: Tue, 9 Jun 2020 22:05:13 +0200
Subject: [PATCH] widget,widget/material: convert Switch to use Clickable

Signed-off-by: Elias Naur <mail@eliasnaur.com>
---
 widget/bool.go            | 41 +++++++++++------------------------
 widget/material/switch.go | 45 +++++++++++++++++++--------------------
 2 files changed, 35 insertions(+), 51 deletions(-)

diff --git a/widget/bool.go b/widget/bool.go
index 9b37dda3..916cdadc 100644
--- a/widget/bool.go
+++ b/widget/bool.go
@@ -1,23 +1,15 @@
 package widget
 
 import (
-	"image"
-	"time"
-
-	"gioui.org/gesture"
-	"gioui.org/io/pointer"
 	"gioui.org/layout"
-	"gioui.org/op"
 )
 
 type Bool struct {
 	Value bool
-	// Last is the last registered click.
-	Last Press
+
+	clk Clickable
 
 	changed bool
-
-	gesture gesture.Click
 }
 
 // Changed reports whether Value has changed since the last
@@ -28,22 +20,15 @@ func (b *Bool) Changed() bool {
 	return changed
 }
 
-func (b *Bool) Layout(gtx layout.Context) layout.Dimensions {
-	for _, e := range b.gesture.Events(gtx) {
-		switch e.Type {
-		case gesture.TypeClick:
-			now := gtx.Now()
-			b.Last = Press{
-				Start:    now,
-				End:      now.Add(time.Second),
-				Position: e.Position,
-			}
-			b.Value = !b.Value
-			b.changed = true
-		}
-	}
-	defer op.Push(gtx.Ops).Pop()
-	pointer.Rect(image.Rectangle{Max: gtx.Constraints.Min}).Add(gtx.Ops)
-	b.gesture.Add(gtx.Ops)
-	return layout.Dimensions{Size: gtx.Constraints.Min}
+func (b *Bool) History() []Press {
+	return b.clk.History()
+}
+
+func (b *Bool) Layout(gtx layout.Context) layout.Dimensions {
+	dims := b.clk.Layout(gtx)
+	for b.clk.Clicked() {
+		b.Value = !b.Value
+		b.changed = true
+	}
+	return dims
 }
diff --git a/widget/material/switch.go b/widget/material/switch.go
index 45b38fe4..3630cff4 100644
--- a/widget/material/switch.go
+++ b/widget/material/switch.go
@@ -51,6 +51,27 @@ func (s SwitchStyle) Layout(gtx layout.Context) layout.Dimensions {
 	paint.PaintOp{Rect: trackRect}.Add(gtx.Ops)
 	stack.Pop()
 
+	// Draw thumb ink.
+	stack = op.Push(gtx.Ops)
+	inkSize := gtx.Px(unit.Dp(44))
+	rr := float32(inkSize) * .5
+	inkOff := f32.Point{
+		X: float32(trackWidth)*.5 - rr,
+		Y: -rr + float32(trackHeight)*.5 + trackOff,
+	}
+	op.TransformOp{}.Offset(inkOff).Add(gtx.Ops)
+	gtx.Constraints.Min = image.Pt(inkSize, inkSize)
+	clip.Rect{
+		Rect: f32.Rectangle{
+			Max: layout.FPt(gtx.Constraints.Min),
+		},
+		NE: rr, NW: rr, SE: rr, SW: rr,
+	}.Op(gtx.Ops).Add(gtx.Ops)
+	for _, p := range s.Switch.History() {
+		drawInk(gtx, p)
+	}
+	stack.Pop()
+
 	// Compute thumb offset and color.
 	stack = op.Push(gtx.Ops)
 	col := rgb(0xffffff)
@@ -73,29 +94,6 @@ func (s SwitchStyle) Layout(gtx layout.Context) layout.Dimensions {
 	drawDisc(gtx.Ops, float32(thumbSize), col)
 	stack.Pop()
 
-	// Draw thumb ink.
-	stack = op.Push(gtx.Ops)
-	inkSize := float32(gtx.Px(unit.Dp(44)))
-	rr := inkSize * .5
-	inkOff := f32.Point{
-		X: float32(trackWidth)*.5 - rr,
-		Y: -rr + float32(trackHeight)*.5 + trackOff,
-	}
-	op.TransformOp{}.Offset(inkOff).Add(gtx.Ops)
-	clip.Rect{
-		Rect: f32.Rectangle{
-			Max: f32.Point{
-				X: inkSize,
-				Y: inkSize,
-			},
-		},
-		NE: rr, NW: rr, SE: rr, SW: rr,
-	}.Op(gtx.Ops).Add(gtx.Ops)
-	dims := image.Point{X: trackWidth, Y: thumbSize}
-	gtx.Constraints.Min = dims
-	drawInk(gtx, s.Switch.Last)
-	stack.Pop()
-
 	// Set up click area.
 	stack = op.Push(gtx.Ops)
 	clickSize := gtx.Px(unit.Dp(40))
@@ -110,6 +108,7 @@ func (s SwitchStyle) Layout(gtx layout.Context) layout.Dimensions {
 	s.Switch.Layout(gtx)
 	stack.Pop()
 
+	dims := image.Point{X: trackWidth, Y: thumbSize}
 	return layout.Dimensions{Size: dims}
 }