Add padding and margin layouts

screen/canvas.go

@@ -43,7 +43,9 @@ func (c Canvas) Build(
 		return
 	}
 
-	decorator = applyDecorators(e, cnv)
+	decorator = applyPadding(e, cnv)
+	decorator = applyDecorators(e, decorator)
+	decorator = applyMargins(e, decorator)
 
 	if e.Hidden {
 		decorator.Hide()

screen/container.go

@@ -67,7 +67,9 @@ func (cnt Container) Build(
 		return
 	}
 
-	decorator = applyDecorators(e, cont)
+	decorator = applyPadding(e, cont)
+	decorator = applyDecorators(e, decorator)
+	decorator = applyMargins(e, decorator)
 
 	if e.Hidden {
 		decorator.Hide()

screen/element.go

@@ -25,6 +25,28 @@ type Color struct {
 	Alpha uint8 `yaml:"alpha"`
 }
 
+type Margins struct {
+	Top    float32 `yaml:"top"`
+	Bottom float32 `yaml:"bottom"`
+	Left   float32 `yaml:"left"`
+	Right  float32 `yaml:"right"`
+}
+
+func (m *Margins) HasMargins() bool {
+	return m.Top > 0 || m.Bottom > 0 || m.Left > 0 || m.Right > 0
+}
+
+type Padding struct {
+	Top    float32 `yaml:"top"`
+	Bottom float32 `yaml:"bottom"`
+	Left   float32 `yaml:"left"`
+	Right  float32 `yaml:"right"`
+}
+
+func (p *Padding) HasPadding() bool {
+	return p.Top > 0 || p.Bottom > 0 || p.Left > 0 || p.Right > 0
+}
+
 // Element represents the yaml description of a ui element
 type Element struct {
 	ID string `yaml:"id"`
@@ -34,6 +56,9 @@ type Element struct {
 	Widget    Widget    `yaml:"widget"`
 	Canvas    Canvas    `yaml:"canvas"`
 
+	Padding Padding `yaml:"padding"`
+	Margins Margins `yaml:"margins"`
+
 	// Border Layout Elements
 	Top    *Element   `yaml:"top"`
 	Bottom *Element   `yaml:"bottom"`

screen/layout.go

@@ -112,7 +112,9 @@ func (l Layout) Build(
 		return
 	}
 
-	decorator = applyDecorators(e, lay)
+	decorator = applyPadding(e, lay)
+	decorator = applyDecorators(e, decorator)
+	decorator = applyMargins(e, decorator)
 
 	if e.Hidden {
 		decorator.Hide()

screen/margin.go

@@ -0,0 +1,25 @@
+package screen
+
+import (
+	"bitbucket.org/hevanto/ui/uilayout"
+	"fyne.io/fyne/v2"
+	"fyne.io/fyne/v2/container"
+)
+
+func applyMargins(
+	e *Element,
+	obj fyne.CanvasObject,
+) (
+	margin fyne.CanvasObject,
+) {
+	margin = obj
+	if e.Margins.HasMargins() {
+		margin = container.New(uilayout.NewMargin(
+			e.Margins.Top,
+			e.Margins.Bottom,
+			e.Margins.Left,
+			e.Margins.Right,
+		), obj)
+	}
+	return
+}

screen/padding.go

@@ -0,0 +1,25 @@
+package screen
+
+import (
+	"bitbucket.org/hevanto/ui/uilayout"
+	"fyne.io/fyne/v2"
+	"fyne.io/fyne/v2/container"
+)
+
+func applyPadding(
+	e *Element,
+	obj fyne.CanvasObject,
+) (
+	padding fyne.CanvasObject,
+) {
+	padding = obj
+	if e.Padding.HasPadding() {
+		padding = container.New(uilayout.NewPadding(
+			e.Padding.Top,
+			e.Padding.Bottom,
+			e.Padding.Left,
+			e.Padding.Right,
+		), obj)
+	}
+	return
+}

screen/widget.go

@@ -255,7 +255,9 @@ func (w Widget) Build(
 		return
 	}
 
-	decorator = applyDecorators(e, widget)
+	decorator = applyPadding(e, widget)
+	decorator = applyDecorators(e, decorator)
+	decorator = applyMargins(e, decorator)
 
 	if e.Hidden {
 		decorator.Hide()

uilayout/margin.go

@@ -0,0 +1,45 @@
+package uilayout
+
+import "fyne.io/fyne/v2"
+
+type Margin struct {
+	top    float32
+	bottom float32
+	left   float32
+	right  float32
+}
+
+func NewMargin(
+	top, bottom, left, right float32,
+) *Margin {
+	return &Margin{
+		top:    top,
+		bottom: bottom,
+		left:   left,
+		right:  right,
+	}
+}
+
+func (m *Margin) MinSize(objects []fyne.CanvasObject) fyne.Size {
+	w := m.left + m.right
+	h := m.top + m.bottom
+	if len(objects) > 0 {
+		w += objects[0].MinSize().Width
+		h += objects[0].MinSize().Height
+	}
+	return fyne.NewSize(w, h)
+}
+
+func (m *Margin) Layout(
+	objects []fyne.CanvasObject,
+	containerSize fyne.Size,
+) {
+	pos := fyne.NewPos(m.left, m.top)
+	if len(objects) > 0 {
+		o := objects[0]
+		size := containerSize.Subtract(
+			fyne.NewSize(m.left+m.right, m.top+m.bottom))
+		o.Resize(size)
+		o.Move(pos)
+	}
+}

uilayout/padding.go

@@ -0,0 +1,45 @@
+package uilayout
+
+import "fyne.io/fyne/v2"
+
+type Padding struct {
+	top    float32
+	bottom float32
+	left   float32
+	right  float32
+}
+
+func NewPadding(
+	top, bottom, left, right float32,
+) *Padding {
+	return &Padding{
+		top:    top,
+		bottom: bottom,
+		left:   left,
+		right:  right,
+	}
+}
+
+func (p *Padding) MinSize(objects []fyne.CanvasObject) fyne.Size {
+	w := p.left + p.right
+	h := p.top + p.bottom
+	if len(objects) > 0 {
+		w += objects[0].MinSize().Width
+		h += objects[0].MinSize().Height
+	}
+	return fyne.NewSize(w, h)
+}
+
+func (p *Padding) Layout(
+	objects []fyne.CanvasObject,
+	containerSize fyne.Size,
+) {
+	pos := fyne.NewPos(p.left, p.top)
+	if len(objects) > 0 {
+		o := objects[0]
+		size := containerSize.Subtract(
+			fyne.NewSize(p.left+p.right, p.top+p.bottom))
+		o.Resize(size)
+		o.Move(pos)
+	}
+}