InputField can now be navigated freely. Resolves #103, resolves #171, resolves #162

This commit is contained in:
Oliver 2018-10-18 08:34:08 +02:00
parent 4a4db5c136
commit 990bc2ebcf
2 changed files with 152 additions and 52 deletions

View File

@ -19,7 +19,7 @@ const logo = `
const (
subtitle = `tview - Rich Widgets for Terminal UIs`
navigation = `Ctrl-N: Next slide Ctrl-P: Previous slide`
navigation = `Ctrl-N: Next slide Ctrl-P: Previous slide Ctrl-C: Exit`
)
// Cover returns the cover page.
@ -45,7 +45,7 @@ func Cover(nextSlide func()) (title string, content tview.Primitive) {
SetBorders(0, 0, 0, 0, 0, 0).
AddText(subtitle, true, tview.AlignCenter, tcell.ColorWhite).
AddText("", true, tview.AlignCenter, tcell.ColorWhite).
AddText(navigation, true, tview.AlignCenter, tcell.ColorBlue)
AddText(navigation, true, tview.AlignCenter, tcell.ColorDarkMagenta)
// Create a Flex layout that centers the logo and subtitle.
flex := tview.NewFlex().

View File

@ -11,10 +11,23 @@ import (
)
// InputField is a one-line box (three lines if there is a title) where the
// user can enter text.
// user can enter text. Use SetAcceptanceFunc() to accept or reject input,
// SetChangedFunc() to listen for changes, and SetMaskCharacter() to hide input
// from onlookers (e.g. for password input).
//
// Use SetMaskCharacter() to hide input from onlookers (e.g. for password
// input).
// The following keys can be used for navigation and editing:
//
// - Left arrow: Move left by one character.
// - Right arrow: Move right by one character.
// - Home, Ctrl-A, Alt-a: Move to the beginning of the line.
// - End, Ctrl-E, Alt-e: Move to the end of the line.
// - Alt-left, Alt-b: Move left by one word.
// - Alt-right, Alt-f: Move right by one word.
// - Backspace: Delete the character before the cursor.
// - Delete: Delete the character after the cursor.
// - Ctrl-K: Delete from the cursor to the end of the line.
// - Ctrl-W: Delete the last word before the cursor.
// - Ctrl-U: Delete the entire line.
//
// See https://github.com/rivo/tview/wiki/InputField for an example.
type InputField struct {
@ -53,6 +66,12 @@ type InputField struct {
// disables masking.
maskCharacter rune
// The cursor position as a byte index into the text string.
cursorPos int
// The number of bytes of the text string skipped ahead while drawing.
offset int
// An optional function which may reject the last character that was entered.
accept func(text string, ch rune) bool
@ -174,7 +193,7 @@ func (i *InputField) SetMaskCharacter(mask rune) *InputField {
// SetAcceptanceFunc sets a handler which may reject the last character that was
// entered (by returning false).
//
// This package defines a number of variables Prefixed with InputField which may
// This package defines a number of variables prefixed with InputField which may
// be used for common input (e.g. numbers, maximum text length).
func (i *InputField) SetAcceptanceFunc(handler func(textToCheck string, lastChar rune) bool) *InputField {
i.accept = handler
@ -244,56 +263,69 @@ func (i *InputField) Draw(screen tcell.Screen) {
screen.SetContent(x+index, y, ' ', nil, fieldStyle)
}
// Draw placeholder text.
// Text.
var cursorScreenPos int
text := i.text
if text == "" && i.placeholder != "" {
Print(screen, i.placeholder, x, y, fieldWidth, AlignLeft, i.placeholderTextColor)
// Draw placeholder text.
Print(screen, Escape(i.placeholder), x, y, fieldWidth, AlignLeft, i.placeholderTextColor)
i.offset = 0
} else {
// Draw entered text.
if i.maskCharacter > 0 {
text = strings.Repeat(string(i.maskCharacter), utf8.RuneCountInString(i.text))
} else {
text = Escape(text)
}
fieldWidth-- // We need one cell for the cursor.
if fieldWidth < runewidth.StringWidth(text) {
Print(screen, text, x, y, fieldWidth, AlignRight, i.fieldTextColor)
stringWidth := runewidth.StringWidth(text)
if fieldWidth >= stringWidth {
// We have enough space for the full text.
Print(screen, Escape(text), x, y, fieldWidth, AlignLeft, i.fieldTextColor)
i.offset = 0
iterateString(text, func(main rune, comb []rune, textPos, textWidth, screenPos, screenWidth int) bool {
if textPos >= i.cursorPos {
return true
}
cursorScreenPos += screenWidth
return false
})
} else {
Print(screen, text, x, y, fieldWidth, AlignLeft, i.fieldTextColor)
// The text doesn't fit. Where is the cursor?
if i.cursorPos < 0 {
i.cursorPos = 0
} else if i.cursorPos > len(text) {
i.cursorPos = len(text)
}
// Shift the text so the cursor is inside the field.
var shiftLeft int
if i.offset > i.cursorPos {
i.offset = i.cursorPos
} else if subWidth := runewidth.StringWidth(text[i.offset:i.cursorPos]); subWidth > fieldWidth-1 {
shiftLeft = subWidth - fieldWidth + 1
}
currentOffset := i.offset
iterateString(text, func(main rune, comb []rune, textPos, textWidth, screenPos, screenWidth int) bool {
if textPos >= currentOffset {
if shiftLeft > 0 {
i.offset = textPos + textWidth
shiftLeft -= screenWidth
} else {
if textPos+textWidth > i.cursorPos {
return true
}
cursorScreenPos += screenWidth
}
}
return false
})
Print(screen, Escape(text[i.offset:]), x, y, fieldWidth, AlignLeft, i.fieldTextColor)
}
}
// Set cursor.
if i.focus.HasFocus() {
i.setCursor(screen)
screen.ShowCursor(x+cursorScreenPos, y)
}
}
// setCursor sets the cursor position.
func (i *InputField) setCursor(screen tcell.Screen) {
x := i.x
y := i.y
rightLimit := x + i.width
if i.border {
x++
y++
rightLimit -= 2
}
fieldWidth := runewidth.StringWidth(i.text)
if i.fieldWidth > 0 && fieldWidth > i.fieldWidth-1 {
fieldWidth = i.fieldWidth - 1
}
if i.labelWidth > 0 {
x += i.labelWidth + fieldWidth
} else {
x += StringWidth(i.label) + fieldWidth
}
if x >= rightLimit {
x = rightLimit - 1
}
screen.ShowCursor(x, y)
}
// InputHandler returns the handler for this primitive.
func (i *InputField) InputHandler() func(event *tcell.EventKey, setFocus func(p Primitive)) {
return i.WrapInputHandler(func(event *tcell.EventKey, setFocus func(p Primitive)) {
@ -305,27 +337,95 @@ func (i *InputField) InputHandler() func(event *tcell.EventKey, setFocus func(p
}
}()
// Movement functions.
home := func() { i.cursorPos = 0 }
end := func() { i.cursorPos = len(i.text) }
moveLeft := func() {
iterateStringReverse(i.text[:i.cursorPos], func(main rune, comb []rune, textPos, textWidth, screenPos, screenWidth int) bool {
i.cursorPos -= textWidth
return true
})
}
moveRight := func() {
iterateString(i.text[i.cursorPos:], func(main rune, comb []rune, textPos, textWidth, screenPos, screenWidth int) bool {
i.cursorPos += textWidth
return true
})
}
moveWordLeft := func() {
i.cursorPos = len(regexp.MustCompile(`\S+\s*$`).ReplaceAllString(i.text[:i.cursorPos], ""))
}
moveWordRight := func() {
i.cursorPos = len(i.text) - len(regexp.MustCompile(`^\s*\S+\s*`).ReplaceAllString(i.text[i.cursorPos:], ""))
}
// Process key event.
switch key := event.Key(); key {
case tcell.KeyRune: // Regular character.
newText := i.text + string(event.Rune())
if i.accept != nil {
if !i.accept(newText, event.Rune()) {
break
modifiers := event.Modifiers()
if modifiers == tcell.ModNone {
ch := string(event.Rune())
newText := i.text[:i.cursorPos] + ch + i.text[i.cursorPos:]
if i.accept != nil {
if !i.accept(newText, event.Rune()) {
break
}
}
i.text = newText
i.cursorPos += len(ch)
} else if modifiers&tcell.ModAlt > 0 {
// We accept some Alt- key combinations.
switch event.Rune() {
case 'a': // Home.
home()
case 'e': // End.
end()
case 'b': // Move word left.
moveWordLeft()
case 'f': // Move word right.
moveWordRight()
}
}
i.text = newText
case tcell.KeyCtrlU: // Delete all.
i.text = ""
i.cursorPos = 0
case tcell.KeyCtrlK: // Delete until the end of the line.
i.text = i.text[:i.cursorPos]
case tcell.KeyCtrlW: // Delete last word.
lastWord := regexp.MustCompile(`\s*\S+\s*$`)
i.text = lastWord.ReplaceAllString(i.text, "")
case tcell.KeyBackspace, tcell.KeyBackspace2: // Delete last character.
if len(i.text) == 0 {
break
lastWord := regexp.MustCompile(`\S+\s*$`)
newText := lastWord.ReplaceAllString(i.text[:i.cursorPos], "") + i.text[i.cursorPos:]
i.cursorPos -= len(i.text) - len(newText)
i.text = newText
case tcell.KeyBackspace, tcell.KeyBackspace2: // Delete character before the cursor.
iterateStringReverse(i.text[:i.cursorPos], func(main rune, comb []rune, textPos, textWidth, screenPos, screenWidth int) bool {
i.text = i.text[:textPos] + i.text[textPos+textWidth:]
i.cursorPos -= textWidth
return true
})
if i.offset >= i.cursorPos {
i.offset = 0
}
runes := []rune(i.text)
i.text = string(runes[:len(runes)-1])
case tcell.KeyDelete: // Delete character after the cursor.
iterateString(i.text[i.cursorPos:], func(main rune, comb []rune, textPos, textWidth, screenPos, screenWidth int) bool {
i.text = i.text[:i.cursorPos] + i.text[i.cursorPos+textWidth:]
return true
})
case tcell.KeyLeft:
if event.Modifiers()&tcell.ModAlt > 0 {
moveWordLeft()
} else {
moveLeft()
}
case tcell.KeyRight:
if event.Modifiers()&tcell.ModAlt > 0 {
moveWordRight()
} else {
moveRight()
}
case tcell.KeyHome, tcell.KeyCtrlA:
home()
case tcell.KeyEnd, tcell.KeyCtrlE:
end()
case tcell.KeyEnter, tcell.KeyTab, tcell.KeyBacktab, tcell.KeyEscape: // We're done.
if i.done != nil {
i.done(key)