add hoverable and tooltip widgets

ui/decredmaterial/hoverable.go

@@ -1,9 +1,62 @@
-package decredmaterial 
+package decredmaterial
+
+import (
+	"image"
+
+	"gioui.org/f32"
+	"gioui.org/io/pointer"
+	"gioui.org/layout"
+	"gioui.org/op"
+)
 
 type Hoverable struct {
-	hovered bool
+	hovered  bool
+	position *f32.Point
 }
 
 func (t *Theme) Hoverable() *Hoverable {
-
-}
+	return &Hoverable{}
+}
+
+func (h *Hoverable) Hovered() bool {
+	return h.hovered
+}
+
+func (h *Hoverable) Position() *f32.Point {
+	return h.position
+}
+
+func (h *Hoverable) update(gtx C) {
+	for _, e := range gtx.Events(h) {
+		ev, ok := e.(pointer.Event)
+		if !ok {
+			continue
+		}
+
+		switch ev.Type {
+		case pointer.Enter:
+			h.hovered = true
+			h.position = &ev.Position
+		case pointer.Leave:
+			h.hovered = false
+			h.position = &f32.Point{}
+		}
+	}
+}
+
+func (h *Hoverable) Layout(gtx C) D {
+	h.update(gtx)
+
+	defer op.Save(gtx.Ops).Load()
+
+	pointer.PassOp{Pass: true}.Add(gtx.Ops)
+	pointer.Rect(image.Rectangle{Max: gtx.Constraints.Min}).Add(gtx.Ops)
+	pointer.InputOp{
+		Tag:   h,
+		Types: pointer.Enter | pointer.Leave,
+	}.Add(gtx.Ops)
+
+	return layout.Dimensions{
+		Size: gtx.Constraints.Min,
+	}
+}

ui/decredmaterial/modal.go

@@ -32,7 +32,7 @@ func (t *Theme) Modal() *Modal {
 func (m *Modal) Layout(gtx layout.Context, widgets []func(gtx C) D, margin int) layout.Dimensions {
 	dims := layout.Stack{}.Layout(gtx,
 		layout.Expanded(func(gtx C) D {
-			fillMax(gtx, m.overlayColor)
+			fillMax(gtx, m.overlayColor, CornerRadius{})
 			return m.button.Layout(gtx)
 		}),
 		layout.Stacked(func(gtx C) D {

ui/decredmaterial/theme.go

@@ -168,14 +168,18 @@ func toPointF(p image.Point) f32.Point {
 	return f32.Point{X: float32(p.X), Y: float32(p.Y)}
 }
 
-func fillMax(gtx layout.Context, col color.NRGBA) D {
+func fillMax(gtx layout.Context, col color.NRGBA, radius CornerRadius) D {
 	cs := gtx.Constraints
 	d := image.Point{X: cs.Max.X, Y: cs.Max.Y}
 	st := op.Save(gtx.Ops)
-	track := image.Rectangle{
-		Max: image.Point{X: d.X, Y: d.Y},
+	track := f32.Rectangle{
+		Max: f32.Point{X: float32(d.X), Y: float32(d.Y)},
 	}
-	clip.Rect(track).Add(gtx.Ops)
+
+	clip.RRect{
+		Rect: track,
+		NE:   radius.NE, NW: radius.NW, SE: radius.SE, SW: radius.SW,
+	}.Add(gtx.Ops)
 	paint.Fill(gtx.Ops, col)
 	st.Load()
 

ui/decredmaterial/tooltip.go

@@ -0,0 +1,96 @@
+package decredmaterial
+
+import (
+	"image"
+	"image/color"
+
+	"gioui.org/layout"
+	"gioui.org/widget"
+	"gioui.org/f32"
+	"gioui.org/op"
+	"gioui.org/unit"
+
+	"github.com/planetdecred/godcr/ui/values"
+)
+
+type Tooltip struct {
+	textLabel                Label
+	position                 Position
+	hoverable                *Hoverable
+	card                     Card
+	hasCalculatedContentDims bool
+	contentDims              image.Point
+	borderColor              color.NRGBA
+}
+
+func (t *Theme) Tooltip(text string, position Position) *Tooltip {
+	return &Tooltip{
+		textLabel:   t.Caption(text),
+		position:    position,
+		hoverable:   t.Hoverable(),
+		card:        t.Card(),
+		borderColor: t.Color.Hint,
+	}
+}
+
+func (t *Tooltip) SetText(text string) {
+	t.textLabel.Text = text
+}
+
+func (t *Tooltip) update(gtx C) {
+	if t.hoverable.Hovered() {
+		t.layoutTooltip(gtx, t.hoverable.Position())
+	}
+}
+
+func (t *Tooltip) calculateContentDims(gtx C) {
+	dims := t.layoutText(gtx)
+	t.contentDims = dims.Size
+}
+
+func (t *Tooltip) layoutText(gtx C) D {
+	border := widget.Border{
+		Color:        t.borderColor,
+		CornerRadius: values.MarginPadding5,
+		Width:        values.MarginPadding1,
+	}
+
+	return layout.Stack{}.Layout(gtx,
+		layout.Stacked(func(gtx C) D {
+			return border.Layout(gtx, func(gtx C) D {
+				return t.card.Layout(gtx, func(gtx C) D {
+					return layout.UniformInset(values.MarginPadding10).Layout(gtx, t.textLabel.Layout)
+				})
+			})
+		}),
+	)
+
+}
+
+func (t *Tooltip) layoutTooltip(gtx C, hoverPosition *f32.Point) D {
+	inset := layout.Inset{}
+	switch t.position {
+	case Left:
+		inset.Left = unit.Dp(-float32(t.contentDims.X) - hoverPosition.X)
+		inset.Top = unit.Dp(hoverPosition.Y + 15)
+	}
+
+	m := op.Record(gtx.Ops)
+	dims := inset.Layout(gtx, t.layoutText)
+	op.Defer(gtx.Ops, m.Stop())
+	return dims
+}
+
+func (t *Tooltip) Layout(gtx C, wdgt layout.Widget) D {
+	if !t.hasCalculatedContentDims {
+		gtx.Constraints.Min = gtx.Constraints.Max
+		t.calculateContentDims(gtx)
+		t.hasCalculatedContentDims = true
+	}
+	t.update(gtx)
+
+	dims := wdgt(gtx)
+	gtx.Constraints.Min = dims.Size
+	t.hoverable.Layout(gtx)
+	return dims
+}