widgets: add list box with filter/scrollbar

Implement a scrollable text box that displays a list of strings which
can be filtered. The widget is closed by pressing ESC or ENTER. If ENTER
is pressed and an entry has been selected, this text will be passed to
the closing callback.

Signed-off-by: Koni Marti <koni.marti@gmail.com>
Acked-by: Robin Jarry <robin@jarry.cc>
This commit is contained in:
Koni Marti 2022-08-08 22:04:03 +02:00 committed by Robin Jarry
parent 00e908e2ae
commit e31dbe9f31
1 changed files with 239 additions and 0 deletions

239
widgets/listbox.go Normal file
View File

@ -0,0 +1,239 @@
package widgets
import (
"math"
"strings"
"sync"
"git.sr.ht/~rjarry/aerc/config"
"git.sr.ht/~rjarry/aerc/lib/ui"
"git.sr.ht/~rjarry/aerc/logging"
"github.com/gdamore/tcell/v2"
)
type ListBox struct {
Scrollable
ui.Invalidatable
title string
lines []string
selected string
cursorPos int
jump int
showCursor bool
showFilter bool
filterMutex sync.Mutex
filter *ui.TextInput
uiConfig *config.UIConfig
cb func(string)
}
func NewListBox(title string, lines []string, uiConfig *config.UIConfig, cb func(string)) *ListBox {
lb := &ListBox{
title: title,
lines: lines,
cursorPos: -1,
jump: -1,
uiConfig: uiConfig,
cb: cb,
filter: ui.NewTextInput("", uiConfig),
}
lb.filter.OnChange(func(ti *ui.TextInput) {
var show bool
if ti.String() == "" {
show = false
} else {
show = true
}
lb.setShowFilterField(show)
lb.filter.Focus(show)
lb.Invalidate()
})
lb.dedup()
return lb
}
func (lb *ListBox) dedup() {
dedupped := make([]string, 0, len(lb.lines))
dedup := make(map[string]struct{})
for _, line := range lb.lines {
if _, dup := dedup[line]; dup {
logging.Warnf("ignore duplicate: %s", line)
continue
}
dedup[line] = struct{}{}
dedupped = append(dedupped, line)
}
lb.lines = dedupped
}
func (lb *ListBox) setShowFilterField(b bool) {
lb.filterMutex.Lock()
defer lb.filterMutex.Unlock()
lb.showFilter = b
}
func (lb *ListBox) showFilterField() bool {
lb.filterMutex.Lock()
defer lb.filterMutex.Unlock()
return lb.showFilter
}
func (lb *ListBox) Draw(ctx *ui.Context) {
defaultStyle := lb.uiConfig.GetStyle(config.STYLE_DEFAULT)
titleStyle := lb.uiConfig.GetStyle(config.STYLE_TITLE)
w, h := ctx.Width(), ctx.Height()
ctx.Fill(0, 0, w, h, ' ', defaultStyle)
ctx.Fill(0, 0, w, 1, ' ', titleStyle)
ctx.Printf(0, 0, titleStyle, "%s", lb.title)
y := 0
if lb.showFilterField() {
y = 1
x := ctx.Printf(0, y, defaultStyle, "Filter: ")
lb.filter.Draw(ctx.Subcontext(x, y, w-x, 1))
}
lb.drawBox(ctx.Subcontext(0, y+1, w, h-(y+1)))
}
func (lb *ListBox) moveCursor(delta int) {
list := lb.filtered()
if len(list) == 0 {
return
}
lb.cursorPos += delta
if lb.cursorPos < 0 {
lb.cursorPos = 0
}
if lb.cursorPos >= len(list) {
lb.cursorPos = len(list) - 1
}
lb.selected = list[lb.cursorPos]
lb.showCursor = true
}
func (lb *ListBox) filtered() []string {
list := []string{}
filterTerm := lb.filter.String()
for _, line := range lb.lines {
if strings.Contains(line, filterTerm) {
list = append(list, line)
}
}
return list
}
func (lb *ListBox) drawBox(ctx *ui.Context) {
defaultStyle := lb.uiConfig.GetStyle(config.STYLE_DEFAULT)
selectedStyle := lb.uiConfig.GetComposedStyleSelected(config.STYLE_MSGLIST_DEFAULT, nil)
w, h := ctx.Width(), ctx.Height()
lb.jump = h
list := lb.filtered()
lb.UpdateScroller(ctx.Height(), len(list))
scroll := 0
lb.cursorPos = -1
for i := 0; i < len(list); i++ {
if lb.selected == list[i] {
scroll = i
lb.cursorPos = i
break
}
}
lb.EnsureScroll(scroll)
needScrollbar := lb.NeedScrollbar()
if needScrollbar {
w -= 1
if w < 0 {
w = 0
}
}
if lb.lines == nil || len(list) == 0 {
return
}
y := 0
for i := lb.Scroll(); i < len(list) && y < h; i++ {
style := defaultStyle
if lb.selected == list[i] && lb.showCursor {
style = selectedStyle
}
ctx.Printf(1, y, style, list[i])
y += 1
}
if needScrollbar {
scrollBarCtx := ctx.Subcontext(w, 0, 1, ctx.Height())
lb.drawScrollbar(scrollBarCtx)
}
}
func (lb *ListBox) drawScrollbar(ctx *ui.Context) {
gutterStyle := tcell.StyleDefault
pillStyle := tcell.StyleDefault.Reverse(true)
// gutter
h := ctx.Height()
ctx.Fill(0, 0, 1, h, ' ', gutterStyle)
// pill
pillSize := int(math.Ceil(float64(h) * lb.PercentVisible()))
pillOffset := int(math.Floor(float64(h) * lb.PercentScrolled()))
ctx.Fill(0, pillOffset, 1, pillSize, ' ', pillStyle)
}
func (lb *ListBox) Invalidate() {
lb.DoInvalidate(lb)
}
func (lb *ListBox) Event(event tcell.Event) bool {
if event, ok := event.(*tcell.EventKey); ok {
switch event.Key() {
case tcell.KeyCtrlP, tcell.KeyUp:
lb.moveCursor(-1)
lb.Invalidate()
return true
case tcell.KeyCtrlN, tcell.KeyDown:
lb.moveCursor(+1)
lb.Invalidate()
return true
case tcell.KeyPgUp:
if lb.jump >= 0 {
lb.moveCursor(-lb.jump)
lb.Invalidate()
}
return true
case tcell.KeyPgDn:
if lb.jump >= 0 {
lb.moveCursor(+lb.jump)
lb.Invalidate()
}
return true
case tcell.KeyEnter:
return lb.quit(lb.selected)
case tcell.KeyEsc:
return lb.quit("")
}
}
if lb.filter != nil {
handled := lb.filter.Event(event)
lb.Invalidate()
return handled
}
return false
}
func (lb *ListBox) quit(s string) bool {
lb.filter.Focus(false)
if lb.cb != nil {
lb.cb(s)
}
return true
}
func (lb *ListBox) Focus(f bool) {
lb.filter.Focus(f)
}