Using tcell.Style for buttons, allowing us to control it better. Resolves #704

box.go

@@ -263,6 +263,12 @@ func (b *Box) SetBorder(show bool) *Box {
 	return b
 }
 
+// SetBorderStyle sets the box's border style.
+func (b *Box) SetBorderStyle(style tcell.Style) *Box {
+	b.borderStyle = style
+	return b
+}
+
 // SetBorderColor sets the box's border color.
 func (b *Box) SetBorderColor(color tcell.Color) *Box {
 	b.borderStyle = b.borderStyle.Foreground(color)

button.go

@@ -10,17 +10,14 @@ import (
 type Button struct {
 	*Box
 
-	// The text to be displayed before the input area.
+	// The text to be displayed inside the button.
-	label string
+	text string
 
-	// The label color.
+	// The button's style (when deactivated).
-	labelColor tcell.Color
+	style tcell.Style
 
-	// The label color when the button is in focus.
+	// The button's style (when activated).
-	labelColorActivated tcell.Color
+	activatedStyle tcell.Style
-
-	// The background color when the button is in focus.
-	backgroundColorActivated tcell.Color
 
 	// An optional function which is called when the button was selected.
 	selected func()
@@ -33,45 +30,56 @@ type Button struct {
 
 // NewButton returns a new input field.
 func NewButton(label string) *Button {
-	box := NewBox().SetBackgroundColor(Styles.ContrastBackgroundColor)
+	box := NewBox()
 	box.SetRect(0, 0, TaggedStringWidth(label)+4, 1)
 	return &Button{
-		Box:                      box,
+		Box:            box,
-		label:                    label,
+		text:           label,
-		labelColor:               Styles.PrimaryTextColor,
+		style:          tcell.StyleDefault.Background(Styles.ContrastBackgroundColor).Foreground(Styles.PrimaryTextColor),
-		labelColorActivated:      Styles.InverseTextColor,
+		activatedStyle: tcell.StyleDefault.Background(Styles.PrimaryTextColor).Foreground(Styles.InverseTextColor),
-		backgroundColorActivated: Styles.PrimaryTextColor,
 	}
 }
 
 // SetLabel sets the button text.
 func (b *Button) SetLabel(label string) *Button {
-	b.label = label
+	b.text = label
 	return b
 }
 
 // GetLabel returns the button text.
 func (b *Button) GetLabel() string {
-	return b.label
+	return b.text
 }
 
 // SetLabelColor sets the color of the button text.
 func (b *Button) SetLabelColor(color tcell.Color) *Button {
-	b.labelColor = color
+	b.style = b.style.Foreground(color)
+	return b
+}
+
+// SetStyle sets the style of the button used when it is not focused.
+func (b *Button) SetStyle(style tcell.Style) *Button {
+	b.style = style
 	return b
 }
 
 // SetLabelColorActivated sets the color of the button text when the button is
 // in focus.
 func (b *Button) SetLabelColorActivated(color tcell.Color) *Button {
-	b.labelColorActivated = color
+	b.activatedStyle = b.activatedStyle.Foreground(color)
 	return b
 }
 
 // SetBackgroundColorActivated sets the background color of the button text when
 // the button is in focus.
 func (b *Button) SetBackgroundColorActivated(color tcell.Color) *Button {
-	b.backgroundColorActivated = color
+	b.activatedStyle = b.activatedStyle.Background(color)
+	return b
+}
+
+// SetActivatedStyle sets the style of the button used when it is focused.
+func (b *Button) SetActivatedStyle(style tcell.Style) *Button {
+	b.activatedStyle = style
 	return b
 }
 
@@ -96,27 +104,27 @@ func (b *Button) SetExitFunc(handler func(key tcell.Key)) *Button {
 // Draw draws this primitive onto the screen.
 func (b *Button) Draw(screen tcell.Screen) {
 	// Draw the box.
-	borderColor := b.GetBorderColor()
+	style := b.style
-	backgroundColor := b.GetBackgroundColor()
+	_, backgroundColor, _ := style.Decompose()
 	if b.HasFocus() {
-		b.SetBackgroundColor(b.backgroundColorActivated)
+		style = b.activatedStyle
-		b.SetBorderColor(b.labelColorActivated)
+		_, backgroundColor, _ = style.Decompose()
+
+		// Highlight button for one drawing cycle.
+		borderColor := b.GetBorderColor()
+		b.SetBorderColor(backgroundColor)
 		defer func() {
 			b.SetBorderColor(borderColor)
 		}()
 	}
+	b.SetBackgroundColor(backgroundColor)
 	b.Box.DrawForSubclass(screen, b)
-	b.backgroundColor = backgroundColor
 
 	// Draw label.
 	x, y, width, height := b.GetInnerRect()
 	if width > 0 && height > 0 {
 		y = y + height/2
-		labelColor := b.labelColor
+		printWithStyle(screen, b.text, x, y, 0, width, AlignCenter, style, true)
-		if b.HasFocus() {
-			labelColor = b.labelColorActivated
-		}
-		Print(screen, b.label, x, y, width, AlignCenter, labelColor)
 	}
 }
 

form.go

@@ -84,11 +84,11 @@ type Form struct {
 	// The text color of the input area.
 	fieldTextColor tcell.Color
 
-	// The background color of the buttons.
+	// The style of the buttons when they are not focused.
-	buttonBackgroundColor tcell.Color
+	buttonStyle tcell.Style
 
-	// The color of the button text.
+	// The style of the buttons when they are focused.
-	buttonTextColor tcell.Color
+	buttonActivatedStyle tcell.Style
 
 	// The last (valid) key that wsa sent to a "finished" handler or -1 if no
 	// such key is known yet.
@@ -103,14 +103,14 @@ func NewForm() *Form {
 	box := NewBox().SetBorderPadding(1, 1, 1, 1)
 
 	f := &Form{
-		Box:                   box,
+		Box:                  box,
-		itemPadding:           1,
+		itemPadding:          1,
-		labelColor:            Styles.SecondaryTextColor,
+		labelColor:           Styles.SecondaryTextColor,
-		fieldBackgroundColor:  Styles.ContrastBackgroundColor,
+		fieldBackgroundColor: Styles.ContrastBackgroundColor,
-		fieldTextColor:        Styles.PrimaryTextColor,
+		fieldTextColor:       Styles.PrimaryTextColor,
-		buttonBackgroundColor: Styles.ContrastBackgroundColor,
+		buttonStyle:          tcell.StyleDefault.Background(Styles.ContrastBackgroundColor).Foreground(Styles.PrimaryTextColor),
-		buttonTextColor:       Styles.PrimaryTextColor,
+		buttonActivatedStyle: tcell.StyleDefault.Background(Styles.PrimaryTextColor).Foreground(Styles.ContrastBackgroundColor),
-		lastFinishedKey:       -1,
+		lastFinishedKey:      -1,
 	}
 
 	return f
@@ -158,15 +158,31 @@ func (f *Form) SetButtonsAlign(align int) *Form {
 	return f
 }
 
-// SetButtonBackgroundColor sets the background color of the buttons.
+// SetButtonBackgroundColor sets the background color of the buttons. This is
+// also the text color of the buttons when they are focused.
 func (f *Form) SetButtonBackgroundColor(color tcell.Color) *Form {
-	f.buttonBackgroundColor = color
+	f.buttonStyle = f.buttonStyle.Background(color)
+	f.buttonActivatedStyle = f.buttonActivatedStyle.Foreground(color)
 	return f
 }
 
-// SetButtonTextColor sets the color of the button texts.
+// SetButtonTextColor sets the color of the button texts. This is also the
+// background of the buttons when they are focused.
 func (f *Form) SetButtonTextColor(color tcell.Color) *Form {
-	f.buttonTextColor = color
+	f.buttonStyle = f.buttonStyle.Foreground(color)
+	f.buttonActivatedStyle = f.buttonActivatedStyle.Background(color)
+	return f
+}
+
+// SetButtonStyle sets the style of the buttons when they are not focused.
+func (f *Form) SetButtonStyle(style tcell.Style) *Form {
+	f.buttonStyle = style
+	return f
+}
+
+// SetButtonActivatedStyle sets the style of the buttons when they are focused.
+func (f *Form) SetButtonActivatedStyle(style tcell.Style) *Form {
+	f.buttonActivatedStyle = style
 	return f
 }
 
@@ -564,10 +580,8 @@ func (f *Form) Draw(screen tcell.Screen) {
 		if buttonWidth > space {
 			buttonWidth = space
 		}
-		button.SetLabelColor(f.buttonTextColor).
+		button.SetStyle(f.buttonStyle).
-			SetLabelColorActivated(f.buttonBackgroundColor).
+			SetActivatedStyle(f.buttonActivatedStyle)
-			SetBackgroundColorActivated(f.buttonTextColor).
-			SetBackgroundColor(f.buttonBackgroundColor)
 
 		buttonIndex := index + len(f.items)
 		positions[buttonIndex].x = x
@@ -671,16 +685,22 @@ func (f *Form) Focus(delegate func(p Primitive)) {
 		}
 	}
 
-	if f.focusedElement < len(f.items) {
+	// Set the handler for all items and buttons.
-		// We're selecting an item.
+	for index, item := range f.items {
-		item := f.items[f.focusedElement]
 		item.SetFinishedFunc(handler)
-		delegate(item)
+		if f.focusedElement == index {
-	} else {
+			func(i FormItem) { // Wrapping might not be necessary anymore in future Go versions.
-		// We're selecting a button.
+				defer delegate(i)
-		button := f.buttons[f.focusedElement-len(f.items)]
+			}(item)
+		}
+	}
+	for index, button := range f.buttons {
 		button.SetExitFunc(handler)
-		delegate(button)
+		if f.focusedElement == index+len(f.items) {
+			func(b *Button) { // Wrapping might not be necessary anymore in future Go versions.
+				defer delegate(b)
+			}(button)
+		}
 	}
 }
 

modal.go

@@ -148,7 +148,7 @@ func (m *Modal) Draw(screen tcell.Screen) {
 	// Calculate the width of this modal.
 	buttonsWidth := 0
 	for _, button := range m.form.buttons {
-		buttonsWidth += TaggedStringWidth(button.label) + 4 + 2
+		buttonsWidth += TaggedStringWidth(button.text) + 4 + 2
 	}
 	buttonsWidth -= 2
 	screenWidth, screenHeight := screen.Size()