Fixed a number of bugs and added missing useful functions.

application.go

@@ -23,6 +23,9 @@ type Application struct {
 	// The root primitive to be seen on the screen.
 	root Primitive
 
+	// Whether or not the application resizes the root primitive.
+	rootAutoSize bool
+
 	// Key overrides.
 	keyOverrides map[tcell.Key]func(p Primitive) bool
 
@@ -103,6 +106,10 @@ func (a *Application) Run() error {
 	}()
 
 	// Draw the screen for the first time.
+	if a.rootAutoSize && a.root != nil {
+		width, height := a.screen.Size()
+		a.root.SetRect(0, 0, width, height)
+	}
 	a.Unlock()
 	a.Draw()
 
@@ -158,6 +165,13 @@ func (a *Application) Run() error {
 				}
 			}
 		case *tcell.EventResize:
+			if a.rootAutoSize && a.root != nil {
+				a.Lock()
+				width, height := a.screen.Size()
+				a.root.SetRect(0, 0, width, height)
+				a.Unlock()
+				a.Draw()
+			}
 			a.Draw()
 		}
 	}
@@ -198,15 +212,26 @@ func (a *Application) Draw() *Application {
 
 // SetRoot sets the root primitive for this application. This function must be
 // called or nothing will be displayed when the application starts.
-func (a *Application) SetRoot(root Primitive) *Application {
+func (a *Application) SetRoot(root Primitive, autoSize bool) *Application {
 	a.Lock()
 	defer a.Unlock()
 
 	a.root = root
+	a.rootAutoSize = autoSize
 
 	return a
 }
 
+// ResizeToFullScreen resizes the given primitive such that it fills the entire
+// screen.
+func (a *Application) ResizeToFullScreen(p Primitive) *Application {
+	a.RLock()
+	width, height := a.screen.Size()
+	a.RUnlock()
+	p.SetRect(0, 0, width, height)
+	return a
+}
+
 // SetFocus sets the focus on a new primitive. All key events will be redirected
 // to that primitive. Callers must ensure that the primitive will handle key
 // events.

button.go

@@ -31,6 +31,7 @@ type Button struct {
 // NewButton returns a new input field.
 func NewButton(label string) *Button {
 	box := NewBox().SetBackgroundColor(tcell.ColorBlue)
+	box.SetRect(0, 0, len([]rune(label))+4, 1)
 	return &Button{
 		Box:                      box,
 		label:                    label,
@@ -92,21 +93,28 @@ func (b *Button) SetBlurFunc(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.borderColor
 	backgroundColor := b.backgroundColor
 	if b.focus.HasFocus() {
 		b.backgroundColor = b.backgroundColorActivated
+		b.borderColor = b.labelColorActivated
+		defer func() {
+			b.borderColor = borderColor
+		}()
 	}
 	b.Box.Draw(screen)
 	b.backgroundColor = backgroundColor
 
 	// Draw label.
 	x, y, width, height := b.GetInnerRect()
-	y = y + height/2
-	labelColor := b.labelColor
-	if b.focus.HasFocus() {
-		labelColor = b.labelColorActivated
+	if width > 0 && height > 0 {
+		y = y + height/2
+		labelColor := b.labelColor
+		if b.focus.HasFocus() {
+			labelColor = b.labelColorActivated
+		}
+		Print(screen, b.label, x, y, width, AlignCenter, labelColor)
 	}
-	Print(screen, b.label, x, y, width, AlignCenter, labelColor)
 
 	if b.focus.HasFocus() {
 		screen.HideCursor()

frame.go

@@ -12,7 +12,7 @@ type frameText struct {
 	Color  tcell.Color // The text color.
 }
 
-// Frame is a wrapper which adds a border around another box. The top area
+// Frame is a wrapper which adds a border around another primitive. The top area
 // (header) and the bottom area (footer) may also contain text.
 type Frame struct {
 	*Box

inputfield.go

@@ -3,52 +3,10 @@ package tview
 import (
 	"math"
 	"regexp"
-	"strconv"
 
 	"github.com/gdamore/tcell"
 )
 
-var (
-	// InputFieldInteger accepts integers.
-	InputFieldInteger func(text string, ch rune) bool
-
-	// InputFieldFloat accepts floating-point numbers.
-	InputFieldFloat func(text string, ch rune) bool
-
-	// InputFieldMaxLength returns an input field accept handler which accepts
-	// input strings up to a given length. Use it like this:
-	//
-	//   inputField.SetAcceptanceFunc(InputFieldMaxLength(10)) // Accept up to 10 characters.
-	InputFieldMaxLength func(maxLength int) func(text string, ch rune) bool
-)
-
-// Package initialization.
-func init() {
-	// Initialize the predefined handlers.
-
-	InputFieldInteger = func(text string, ch rune) bool {
-		if text == "-" {
-			return true
-		}
-		_, err := strconv.Atoi(text)
-		return err == nil
-	}
-
-	InputFieldFloat = func(text string, ch rune) bool {
-		if text == "-" || text == "." {
-			return true
-		}
-		_, err := strconv.ParseFloat(text, 64)
-		return err == nil
-	}
-
-	InputFieldMaxLength = func(maxLength int) func(text string, ch rune) bool {
-		return func(text string, ch rune) bool {
-			return len([]rune(text)) <= maxLength
-		}
-	}
-}
-
 // InputField is a one-line box (three lines if there is a title) where the
 // user can enter text.
 type InputField struct {
@@ -229,7 +187,7 @@ func (i *InputField) setCursor(screen tcell.Screen) {
 		rightLimit -= 2
 	}
 	fieldLength := len([]rune(i.text))
-	if fieldLength > i.fieldLength-1 {
+	if i.fieldLength > 0 && fieldLength > i.fieldLength-1 {
 		fieldLength = i.fieldLength - 1
 	}
 	x += len([]rune(i.label)) + fieldLength

pages.go

@@ -1,6 +1,8 @@
 package tview
 
-import "github.com/gdamore/tcell"
+import (
+	"github.com/gdamore/tcell"
+)
 
 // page represents one page of a Pages object.
 type page struct {
@@ -18,6 +20,10 @@ type Pages struct {
 	// The contained pages.
 	pages []*page
 
+	// We keep a reference to the function which allows us to set the focus to
+	// a newly visible page.
+	setFocus func(p Primitive)
+
 	// An optional handler which is called whenever the visibility or the order of
 	// pages changes.
 	changed func()
@@ -46,10 +52,11 @@ func (p *Pages) SetChangedFunc(handler func()) *Pages {
 // Visible pages will be drawn in the order they were added (unless that order
 // was changed in one of the other functions).
 func (p *Pages) AddPage(name string, item Primitive, visible bool) *Pages {
-	p.pages = append(p.pages, &page{Item: item, Name: name, Visible: true})
+	p.pages = append(p.pages, &page{Item: item, Name: name, Visible: visible})
 	if p.changed != nil {
 		p.changed()
 	}
+	p.refocus()
 	return p
 }
 
@@ -64,6 +71,7 @@ func (p *Pages) RemovePage(name string) *Pages {
 			break
 		}
 	}
+	p.refocus()
 	return p
 }
 
@@ -79,6 +87,7 @@ func (p *Pages) ShowPage(name string) *Pages {
 			break
 		}
 	}
+	p.refocus()
 	return p
 }
 
@@ -93,6 +102,7 @@ func (p *Pages) HidePage(name string) *Pages {
 			break
 		}
 	}
+	p.refocus()
 	return p
 }
 
@@ -109,6 +119,7 @@ func (p *Pages) SwitchToPage(name string) *Pages {
 	if p.changed != nil {
 		p.changed()
 	}
+	p.refocus()
 	return p
 }
 
@@ -127,6 +138,7 @@ func (p *Pages) SendToFront(name string) *Pages {
 			break
 		}
 	}
+	p.refocus()
 	return p
 }
 
@@ -145,6 +157,7 @@ func (p *Pages) SendToBack(name string) *Pages {
 			break
 		}
 	}
+	p.refocus()
 	return p
 }
 
@@ -158,6 +171,36 @@ func (p *Pages) HasFocus() bool {
 	return false
 }
 
+// Focus is called by the application when the primitive receives focus.
+func (p *Pages) Focus(delegate func(p Primitive)) {
+	p.setFocus = delegate
+	var topItem Primitive
+	for _, page := range p.pages {
+		if page.Visible {
+			topItem = page.Item
+		}
+	}
+	if topItem != nil {
+		delegate(topItem)
+	}
+}
+
+// refocus sets the focus to the topmost visible page but only if we have focus.
+func (p *Pages) refocus() {
+	if !p.HasFocus() || p.setFocus == nil {
+		return
+	}
+	var topItem Primitive
+	for _, page := range p.pages {
+		if page.Visible {
+			topItem = page.Item
+		}
+	}
+	if topItem != nil {
+		p.setFocus(topItem)
+	}
+}
+
 // Draw draws this primitive onto the screen.
 func (p *Pages) Draw(screen tcell.Screen) {
 	for _, page := range p.pages {
@@ -167,3 +210,8 @@ func (p *Pages) Draw(screen tcell.Screen) {
 		page.Item.Draw(screen)
 	}
 }
+
+// InputHandler returns the handler for this primitive.
+func (p *Pages) InputHandler() func(event *tcell.EventKey, setFocus func(p Primitive)) {
+	return func(event *tcell.EventKey, setFocus func(p Primitive)) {}
+}

textview.go

@@ -272,6 +272,14 @@ func (t *TextView) Highlight(regionIDs ...string) *TextView {
 	return t
 }
 
+// GetHighlights returns the IDs of all currently highlighted regions.
+func (t *TextView) GetHighlights() (regionIDs []string) {
+	for id := range t.highlights {
+		regionIDs = append(regionIDs, id)
+	}
+	return
+}
+
 // ScrollToHighlight will cause the visible area to be scrolled so that the
 // highlighted regions appear in the visible area of the text view. This
 // repositioning happens the next time the text view is drawn. It happens only
@@ -452,6 +460,16 @@ func (t *TextView) reindexBuffer(width int) {
 			regions = regionPattern.FindAllStringSubmatch(str, -1)
 		}
 
+		// We also keep a reference to empty lines.
+		if len(str) == 0 {
+			t.index = append(t.index, &textViewIndex{
+				Line:   index,
+				Pos:    0,
+				Color:  color,
+				Region: regionID,
+			})
+		}
+
 		// Break down the line.
 		var currentTag, currentRegion, currentWidth int
 		for pos := range str {

util.go

@@ -2,6 +2,7 @@ package tview
 
 import (
 	"math"
+	"strconv"
 	"strings"
 
 	"github.com/gdamore/tcell"
@@ -36,6 +37,47 @@ const (
 	GraphicsEllipsis            = '\u2026'
 )
 
+var (
+	// InputFieldInteger accepts integers.
+	InputFieldInteger func(text string, ch rune) bool
+
+	// InputFieldFloat accepts floating-point numbers.
+	InputFieldFloat func(text string, ch rune) bool
+
+	// InputFieldMaxLength returns an input field accept handler which accepts
+	// input strings up to a given length. Use it like this:
+	//
+	//   inputField.SetAcceptanceFunc(InputFieldMaxLength(10)) // Accept up to 10 characters.
+	InputFieldMaxLength func(maxLength int) func(text string, ch rune) bool
+)
+
+// Package initialization.
+func init() {
+	// Initialize the predefined handlers.
+
+	InputFieldInteger = func(text string, ch rune) bool {
+		if text == "-" {
+			return true
+		}
+		_, err := strconv.Atoi(text)
+		return err == nil
+	}
+
+	InputFieldFloat = func(text string, ch rune) bool {
+		if text == "-" || text == "." {
+			return true
+		}
+		_, err := strconv.ParseFloat(text, 64)
+		return err == nil
+	}
+
+	InputFieldMaxLength = func(maxLength int) func(text string, ch rune) bool {
+		return func(text string, ch rune) bool {
+			return len([]rune(text)) <= maxLength
+		}
+	}
+}
+
 // Print prints text onto the screen into the given box at (x,y,maxWidth,1),
 // no exceeding that box.  "align" is one of AlignLeft, AlignCenter, or
 // AlignRight. The screen's background color will be maintained.