Browse Source

Added regions and highlights to TextView.

tablepad
Oliver 5 years ago
parent
commit
f5788cfc52
  1. 12
      application.go
  2. 2
      box.go
  3. 27
      demos/basic.go
  4. 373
      textview.go

12
application.go

@ -32,13 +32,16 @@ func NewApplication() *Application {
// when Stop() was called.
func (a *Application) Run() error {
var err error
a.Lock()
// Make a screen.
a.screen, err = tcell.NewScreen()
if err != nil {
a.Unlock()
return err
}
if err = a.screen.Init(); err != nil {
a.Unlock()
return err
}
@ -57,6 +60,7 @@ func (a *Application) Run() error {
width, height := a.screen.Size()
a.root.SetRect(0, 0, width, height)
}
a.Unlock()
a.Draw()
// Start event loop.
@ -86,8 +90,8 @@ func (a *Application) Run() error {
}
case *tcell.EventResize:
if a.rootAutoSize && a.root != nil {
width, height := a.screen.Size()
a.Lock()
width, height := a.screen.Size()
a.root.SetRect(0, 0, width, height)
a.Unlock()
a.Draw()
@ -114,14 +118,12 @@ func (a *Application) Draw() *Application {
defer a.Unlock()
// Maybe we're not ready yet or not anymore.
if a.screen == nil {
if a.screen == nil || a.root == nil {
return a
}
// Draw all primitives.
if a.root != nil {
a.root.Draw(a.screen)
}
a.root.Draw(a.screen)
// Sync screen.
a.screen.Show()

2
box.go

@ -67,7 +67,7 @@ func NewBox() *Box {
return b
}
// SetPadding sets the size of the borders around the box content.
// SetBorderPadding sets the size of the borders around the box content.
func (b *Box) SetBorderPadding(top, bottom, left, right int) *Box {
b.paddingTop, b.paddingBottom, b.paddingLeft, b.paddingRight = top, bottom, left, right
return b

27
demos/basic.go

@ -2,8 +2,6 @@ package main
import (
"fmt"
"io"
"net/http"
"github.com/gdamore/tcell"
"github.com/rivo/tview"
@ -45,26 +43,19 @@ func main() {
})
form.SetTitle("Customer").SetBorder(true)
textView := tview.NewTextView().
SetWrap(false).
SetDynamicColors(false).
textView := tview.NewTextView()
textView.SetWrap(true).
SetDynamicColors(true).
SetScrollable(true).
SetRegions(true).
SetChangedFunc(func() { app.Draw() }).
SetDoneFunc(func(key tcell.Key) { app.SetFocus(list) })
SetDoneFunc(func(key tcell.Key) { textView.ScrollToHighlight(); app.SetFocus(list) })
textView.SetBorder(true).SetTitle("Text view")
go func() {
url := "https://www.rentafounder.com"
fmt.Fprintf(textView, "Reading from: %s\n\n", url)
resp, err := http.Get(url)
if err != nil {
fmt.Fprint(textView, err)
return
for i := 0; i < 200; i++ {
fmt.Fprintf(textView, "[\"%d\"]%d\n", i, i)
}
defer resp.Body.Close()
n, err := io.Copy(textView, resp.Body)
if err != nil {
fmt.Fprint(textView, err)
}
fmt.Fprintf(textView, "\n\n%d bytes read", n)
textView.Highlight("199")
}()
list = tview.NewList().

373
textview.go

@ -1,6 +1,7 @@
package tview
import (
"bytes"
"math"
"regexp"
"sync"
@ -19,33 +20,77 @@ var textColors = map[string]tcell.Color{
"green": tcell.ColorGreen,
}
// A regular expression commonly used throughout the TextView class.
var colorPattern = regexp.MustCompile(`\[(white|yellow|blue|green|red)\]`)
// Regular expressions commonly used throughout the TextView class.
var (
colorPattern = regexp.MustCompile(`\[(white|yellow|blue|green|red)\]`)
regionPattern = regexp.MustCompile(`\["([a-zA-Z0-9_,;: \-\.]*)"\]`)
)
// textViewIndex contains information about each line displayed in the text
// view.
type textViewIndex struct {
Line int // The index into the "buffer" variable.
Pos int // The index into the "buffer" string.
Color tcell.Color // The starting color.
Line int // The index into the "buffer" variable.
Pos int // The index into the "buffer" string.
Color tcell.Color // The starting color.
Region string // The starting region ID.
}
// TextView is a box which displays text. It implements the Reader interface so
// you can stream text to it.
// TextView is a box which displays text. It implements the io.Writer interface
// so you can stream text to it. This does not trigger a redraw automatically
// but if a handler is installed via SetChangedFunc(), you can cause it to be
// redrawn.
//
// Navigation
//
// If the text view is scrollable (the default), text is kept in a buffer and
// can be navigated using the arrow keys, Ctrl-F and Ctrl-B for page jumps, "g"
// for the beginning of the text, and "G" for the end of the text.
// If the text view is scrollable (the default), text is kept in a buffer which
// may be larger than the screen and can be navigated similarly to Vim:
//
// - h, left arrow: Move left.
// - l, right arrow: Move right.
// - j, down arrow: Move down.
// - k, up arrow: Move up.
// - g, home: Move to the beginning.
// - G, end: Move to the end.
// - Ctrl-F, page down: Move down by one page.
// - Ctrl-B, page up: Move up by one page.
//
// If the text is not scrollable, any text above the top line is discarded.
//
// If dynamic colors are enabled, text color can be changed dynamically by
// embedding it into square brackets. For example,
// Navigation can be intercepted by installing a callback function via
// SetCaptureFunc() which receives all keyboard events and decides which ones
// to forward to the default handler.
//
// Colors
//
// "This is a [red]warning[white]!"
// If dynamic colors are enabled via SetDynamicColors(), text color can be
// changed dynamically by embedding color strings in square brackets. For
// example,
//
// This is a [red]warning[white]!
//
// will print the word "warning" in red. The following colors are currently
// supported: white, yellow, blue, green, red.
//
// Regions and Highlights
//
// If regions are enabled via SetRegions(), you can define text regions within
// the text and assign region IDs to them. Text regions start with region tags.
// Region tags are square brackets that contain a region ID in double quotes,
// for example:
//
// We define a ["rg"]region[""] here.
//
// A text region ends with the next region tag. Tags with no region ID ([""])
// don't start new regions. They can therefore be used to mark the end of a
// region. Region IDs must satisfy the following regular expression:
//
// [a-zA-Z0-9_,;: \-\.]+
//
// Regions can be highlighted by calling the Highlight() function with one or
// more region IDs. This can be used to display search results, for example.
//
// The ScrollToHighlight() function can be used to jump to the currently
// highlighted region once when the text view is drawn the next time.
type TextView struct {
sync.Mutex
*Box
@ -53,16 +98,24 @@ type TextView struct {
// The text buffer.
buffer []string
// The last bytes that have been received but are not part of the buffer yet.
recentBytes []byte
// The processed line index. This is nil if the buffer has changed and needs
// to be re-indexed.
index []*textViewIndex
// Indices into the "index" slice which correspond to the first line of the
// first highlight and the last line of the last highlight. This is calculated
// during re-indexing. Set to -1 if there is no current highlight.
fromHighlight, toHighlight int
// A set of region IDs that are currently highlighted.
highlights map[string]struct{}
// The display width for which the index is created.
indexWidth int
// The last bytes that have been received but are not part of the buffer yet.
recentBytes []byte
// The index of the first line shown in the text view.
lineOffset int
@ -91,6 +144,17 @@ type TextView struct {
// strings in square brackets to the text view.
dynamicColors bool
// If set to true, region tags can be used to define regions.
regions bool
// A temporary flag which, when true, will automatically bring the current
// highlight(s) into the visible screen.
scrollToHighlights bool
// An optional function which will receive all key events sent to this text
// view. Returning true also invokes the default key handling.
capture func(*tcell.EventKey) bool
// An optional function which is called when the content of the text view has
// changed.
changed func()
@ -104,11 +168,12 @@ type TextView struct {
func NewTextView() *TextView {
return &TextView{
Box: NewBox(),
highlights: make(map[string]struct{}),
lineOffset: -1,
scrollable: true,
wrap: true,
textColor: tcell.ColorWhite,
dynamicColors: true,
dynamicColors: false,
}
}
@ -139,7 +204,7 @@ func (t *TextView) SetTextColor(color tcell.Color) *TextView {
}
// SetDynamicColors sets the flag that allows the text color to be changed
// dynamically. See type description for details.
// dynamically. See class description for details.
func (t *TextView) SetDynamicColors(dynamic bool) *TextView {
if t.dynamicColors != dynamic {
t.index = nil
@ -148,6 +213,22 @@ func (t *TextView) SetDynamicColors(dynamic bool) *TextView {
return t
}
// SetRegions sets the flag that allows to define regions in the text. See class
// description for details.
func (t *TextView) SetRegions(regions bool) *TextView {
t.regions = regions
return t
}
// SetCaptureFunc sets a handler which is called whenever a key is pressed.
// This allows you to override the default key handling of the text view.
// Returning true will allow the default key handling to go forward after the
// handler returns. Returning false will disable any default key handling.
func (t *TextView) SetCaptureFunc(handler func(event *tcell.EventKey) bool) *TextView {
t.capture = handler
return t
}
// SetChangedFunc sets a handler function which is called when the text of the
// text view has changed. This is typically used to cause the application to
// redraw the screen.
@ -172,6 +253,115 @@ func (t *TextView) Clear() *TextView {
return t
}
// Highlight specifies which regions should be highlighted. See class
// description for details on regions. Empty region strings are ignored.
//
// Text in highlighted regions will be drawn inverted, i.e. with their
// background and foreground colors swapped.
//
// Calling this function will remove any previous highlights. To remove all
// highlights, call this function without any arguments.
func (t *TextView) Highlight(regionIDs ...string) *TextView {
t.highlights = make(map[string]struct{})
for _, id := range regionIDs {
if id == "" {
continue
}
t.highlights[id] = struct{}{}
}
return t
}
// 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
// once so you will need to call this function repeatedly to always keep
// highlighted regions in view.
//
// Nothing happens if there are no highlighted regions or if the text view is
// not scrollable.
func (t *TextView) ScrollToHighlight() *TextView {
if len(t.highlights) == 0 || !t.scrollable || !t.regions {
return t
}
t.index = nil
t.scrollToHighlights = true
t.trackEnd = false
return t
}
// GetRegionText returns the text of the region with the given ID. If dynamic
// colors are enabled, color tags are stripped from the text. Newlines are
// always returned as '\n' runes.
//
// If the region does not exist or if regions are turned off, an empty string
// is returned.
func (t *TextView) GetRegionText(regionID string) string {
if !t.regions || regionID == "" {
return ""
}
var (
buffer bytes.Buffer
currentRegionID string
)
for _, str := range t.buffer {
// Find all color tags in this line.
var colorTagIndices [][]int
if t.dynamicColors {
colorTagIndices = colorPattern.FindAllStringIndex(str, -1)
}
// Find all regions in this line.
var (
regionIndices [][]int
regions [][]string
)
if t.regions {
regionIndices = regionPattern.FindAllStringIndex(str, -1)
regions = regionPattern.FindAllStringSubmatch(str, -1)
}
// Analyze this line.
var currentTag, currentRegion int
for pos, ch := range str {
// Skip any color tags.
if currentTag < len(colorTagIndices) && pos >= colorTagIndices[currentTag][0] && pos < colorTagIndices[currentTag][1] {
if pos == colorTagIndices[currentTag][1]-1 {
currentTag++
}
continue
}
// Skip any regions.
if currentRegion < len(regionIndices) && pos >= regionIndices[currentRegion][0] && pos < regionIndices[currentRegion][1] {
if pos == regionIndices[currentRegion][1]-1 {
if currentRegionID == regionID {
// This is the end of the requested region. We're done.
return buffer.String()
}
currentRegionID = regions[currentRegion][1]
currentRegion++
}
continue
}
// Add this rune.
if currentRegionID == regionID {
buffer.WriteRune(ch)
}
}
// Add newline.
if currentRegionID == regionID {
buffer.WriteRune('\n')
}
}
return buffer.String()
}
// Write lets us implement the io.Writer interface.
func (t *TextView) Write(p []byte) (n int, err error) {
// Notify at the end.
@ -231,7 +421,12 @@ func (t *TextView) reindexBuffer(width int) {
return // Nothing has changed. We can still use the current index.
}
t.index = nil
t.fromHighlight, t.toHighlight = -1, -1
var (
regionID string
highlighted bool
)
color := t.textColor
if !t.wrap {
width = math.MaxInt64
@ -247,28 +442,63 @@ func (t *TextView) reindexBuffer(width int) {
colorTags = colorPattern.FindAllStringSubmatch(str, -1)
}
// Find all regions in this line.
var (
regionIndices [][]int
regions [][]string
)
if t.regions {
regionIndices = regionPattern.FindAllStringIndex(str, -1)
regions = regionPattern.FindAllStringSubmatch(str, -1)
}
// Break down the line.
var currentTag, currentWidth int
var currentTag, currentRegion, currentWidth int
for pos := range str {
// Skip any color tags.
if currentTag < len(colorTags) {
if pos >= colorTagIndices[currentTag][0] && pos < colorTagIndices[currentTag][1] {
if currentTag < len(colorTags) && pos >= colorTagIndices[currentTag][0] && pos < colorTagIndices[currentTag][1] {
if pos == colorTagIndices[currentTag][1]-1 {
color = textColors[colorTags[currentTag][1]]
continue
} else if pos >= colorTagIndices[currentTag][1] {
currentTag++
}
continue
}
// Check regions.
if currentRegion < len(regionIndices) && pos >= regionIndices[currentRegion][0] && pos < regionIndices[currentRegion][1] {
if pos == regionIndices[currentRegion][1]-1 {
// We're done with this region.
regionID = regions[currentRegion][1]
// Is this region highlighted?
_, highlighted = t.highlights[regionID]
currentRegion++
}
continue
}
// Add this line.
if currentWidth == 0 {
t.index = append(t.index, &textViewIndex{
Line: index,
Pos: pos,
Color: color,
Line: index,
Pos: pos,
Color: color,
Region: regionID,
})
}
// Update highlight range.
if highlighted {
line := len(t.index) - 1
if t.fromHighlight < 0 {
t.fromHighlight, t.toHighlight = line, line
} else if line > t.toHighlight {
t.toHighlight = line
}
}
// Proceed.
currentWidth++
// Have we crossed the width?
@ -294,6 +524,19 @@ func (t *TextView) Draw(screen tcell.Screen) {
// Re-index.
t.reindexBuffer(width)
// Move to highlighted regions.
if t.regions && t.scrollToHighlights && t.fromHighlight >= 0 {
// Do we fit the entire height?
if t.toHighlight-t.fromHighlight+1 < height {
// Yes, let's center the highlights.
t.lineOffset = (t.fromHighlight + t.toHighlight - height) / 2
} else {
// No, let's move to the start of the highlights.
t.lineOffset = t.fromHighlight
}
}
t.scrollToHighlights = false
// Adjust line offset.
if t.lineOffset+height > len(t.index) {
t.trackEnd = true
@ -306,7 +549,6 @@ func (t *TextView) Draw(screen tcell.Screen) {
}
// Draw the buffer.
style := tcell.StyleDefault.Background(t.backgroundColor)
for line := t.lineOffset; line < len(t.index); line++ {
// Are we done?
if line-t.lineOffset >= height {
@ -316,7 +558,8 @@ func (t *TextView) Draw(screen tcell.Screen) {
// Get the text for this line.
index := t.index[line]
text := t.buffer[index.Line][index.Pos:]
style = style.Foreground(index.Color)
color := index.Color
regionID := index.Region
// Get color tags.
var (
@ -328,16 +571,35 @@ func (t *TextView) Draw(screen tcell.Screen) {
colorTags = colorPattern.FindAllStringSubmatch(text, -1)
}
// Get regions.
var (
regionIndices [][]int
regions [][]string
)
if t.regions {
regionIndices = regionPattern.FindAllStringIndex(text, -1)
regions = regionPattern.FindAllStringSubmatch(text, -1)
}
// Print one line.
var currentTag, skip, posX int
var currentTag, currentRegion, skip, posX int
for pos, ch := range text {
if currentTag < len(colorTags) {
if pos >= colorTagIndices[currentTag][0] && pos < colorTagIndices[currentTag][1] {
style = style.Foreground(textColors[colorTags[currentTag][1]])
continue
} else if pos >= colorTagIndices[currentTag][1] {
// Get the color.
if currentTag < len(colorTags) && pos >= colorTagIndices[currentTag][0] && pos < colorTagIndices[currentTag][1] {
if pos == colorTagIndices[currentTag][1]-1 {
color = textColors[colorTags[currentTag][1]]
currentTag++
}
continue
}
// Get the region.
if currentRegion < len(regionIndices) && pos >= regionIndices[currentRegion][0] && pos < regionIndices[currentRegion][1] {
if pos == regionIndices[currentRegion][1]-1 {
regionID = regions[currentRegion][1]
currentRegion++
}
continue
}
// Skip to the right.
@ -351,17 +613,54 @@ func (t *TextView) Draw(screen tcell.Screen) {
break
}
// Do we highlight this character?
style := tcell.StyleDefault.Background(t.backgroundColor).Foreground(color)
if len(regionID) > 0 {
if _, ok := t.highlights[regionID]; ok {
style = tcell.StyleDefault.Background(color).Foreground(t.backgroundColor)
}
}
// Draw the character.
screen.SetContent(x+posX, y+line-t.lineOffset, ch, nil, style)
// Advance.
posX++
}
}
// If this view is not scrollable, we'll purge the buffer of lines that have
// scrolled out of view.
if !t.scrollable && t.lineOffset > 0 {
t.buffer = t.buffer[t.index[t.lineOffset].Line:]
t.index = nil
}
}
// InputHandler returns the handler for this primitive.
func (t *TextView) InputHandler() func(event *tcell.EventKey, setFocus func(p Primitive)) {
return func(event *tcell.EventKey, setFocus func(p Primitive)) {
switch key := event.Key(); key {
// Do we pass this event on?
if t.capture != nil {
if !t.capture(event) {
return
}
}
key := event.Key()
if key == tcell.KeyEscape || key == tcell.KeyEnter || key == tcell.KeyTab || key == tcell.KeyBacktab {
if t.done != nil {
t.done(key)
}
return
}
if !t.scrollable {
return
}
switch key {
case tcell.KeyRune:
switch event.Rune() {
case 'g': // Home.
@ -408,10 +707,6 @@ func (t *TextView) InputHandler() func(event *tcell.EventKey, setFocus func(p Pr
case tcell.KeyPgUp, tcell.KeyCtrlB:
t.trackEnd = false
t.lineOffset -= t.pageSize
case tcell.KeyEscape, tcell.KeyEnter, tcell.KeyTab, tcell.KeyBacktab:
if t.done != nil {
t.done(key)
}
}
}
}

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