tview/demos/primitive/main.go

93 lines
2.5 KiB
Go

// Demo code which illustrates how to implement your own primitive.
package main
import (
"fmt"
"github.com/gdamore/tcell/v2"
"github.com/rivo/tview"
)
// RadioButtons implements a simple primitive for radio button selections.
type RadioButtons struct {
*tview.Box
options []string
currentOption int
}
// NewRadioButtons returns a new radio button primitive.
func NewRadioButtons(options []string) *RadioButtons {
return &RadioButtons{
Box: tview.NewBox(),
options: options,
}
}
// Draw draws this primitive onto the screen.
func (r *RadioButtons) Draw(screen tcell.Screen) {
r.Box.DrawForSubclass(screen, r)
x, y, width, height := r.GetInnerRect()
for index, option := range r.options {
if index >= height {
break
}
radioButton := "\u25ef" // Unchecked.
if index == r.currentOption {
radioButton = "\u25c9" // Checked.
}
line := fmt.Sprintf(`%s[white] %s`, radioButton, option)
tview.Print(screen, line, x, y+index, width, tview.AlignLeft, tcell.ColorYellow)
}
}
// InputHandler returns the handler for this primitive.
func (r *RadioButtons) InputHandler() func(event *tcell.EventKey, setFocus func(p tview.Primitive)) {
return r.WrapInputHandler(func(event *tcell.EventKey, setFocus func(p tview.Primitive)) {
switch event.Key() {
case tcell.KeyUp:
r.currentOption--
if r.currentOption < 0 {
r.currentOption = 0
}
case tcell.KeyDown:
r.currentOption++
if r.currentOption >= len(r.options) {
r.currentOption = len(r.options) - 1
}
}
})
}
// MouseHandler returns the mouse handler for this primitive.
func (r *RadioButtons) MouseHandler() func(action tview.MouseAction, event *tcell.EventMouse, setFocus func(p tview.Primitive)) (consumed bool, capture tview.Primitive) {
return r.WrapMouseHandler(func(action tview.MouseAction, event *tcell.EventMouse, setFocus func(p tview.Primitive)) (consumed bool, capture tview.Primitive) {
x, y := event.Position()
_, rectY, _, _ := r.GetInnerRect()
if !r.InRect(x, y) {
return false, nil
}
if action == tview.MouseLeftClick {
setFocus(r)
index := y - rectY
if index >= 0 && index < len(r.options) {
r.currentOption = index
consumed = true
}
}
return
})
}
func main() {
radioButtons := NewRadioButtons([]string{"Lions", "Elephants", "Giraffes"})
radioButtons.SetBorder(true).
SetTitle("Radio Button Demo").
SetRect(0, 0, 30, 5)
if err := tview.NewApplication().SetRoot(radioButtons, false).EnableMouse(true).Run(); err != nil {
panic(err)
}
}