Bubble Tea simple list example with filtering

main.go

package main

import (
	"fmt"
	"io"
	"os"

	"github.com/charmbracelet/bubbles/list"
	tea "github.com/charmbracelet/bubbletea"
	"github.com/charmbracelet/lipgloss"
)

const listHeight = 14

var (
	titleStyle        = lipgloss.NewStyle().MarginLeft(2)
	itemStyle         = lipgloss.NewStyle().PaddingLeft(4)
	selectedItemStyle = lipgloss.NewStyle().PaddingLeft(2).Foreground(lipgloss.Color("170"))
	paginationStyle   = list.DefaultStyles().PaginationStyle.PaddingLeft(4)
	helpStyle         = list.DefaultStyles().HelpStyle.PaddingLeft(4).PaddingBottom(1)
	quitTextStyle     = lipgloss.NewStyle().Margin(1, 0, 2, 4)
)

type item string

func (i item) FilterValue() string { return string(i) }

type itemDelegate struct{}

func (d itemDelegate) Height() int                               { return 1 }
func (d itemDelegate) Spacing() int                              { return 0 }
func (d itemDelegate) Update(msg tea.Msg, m *list.Model) tea.Cmd { return nil }
func (d itemDelegate) Render(w io.Writer, m list.Model, index int, listItem list.Item) {
	i, ok := listItem.(item)
	if !ok {
		return
	}

	str := fmt.Sprintf("%d. %s", index+1, i)

	fn := itemStyle.Render
	if index == m.Index() {
		fn = func(s string) string {
			return selectedItemStyle.Render("> " + s)
		}
	}

	fmt.Fprintf(w, fn(str))
}

type model struct {
	list     list.Model
	items    []item
	choice   string
	quitting bool
}

func (m model) Init() tea.Cmd {
	return nil
}

func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
	switch msg := msg.(type) {
	case tea.WindowSizeMsg:
		m.list.SetWidth(msg.Width)
		return m, nil

	case tea.KeyMsg:
		switch keypress := msg.String(); keypress {
		case "ctrl+c":
			m.quitting = true
			return m, tea.Quit

		case "enter":
			if m.list.FilterState() != list.Filtering {
				i, ok := m.list.SelectedItem().(item)
				if ok {
					m.choice = string(i)
				}
				return m, tea.Quit
			}

		default:
			if !m.list.SettingFilter() && (keypress == "q" || keypress == "esc") {
				m.quitting = true
				return m, tea.Quit
			}
		}
	}

	var cmd tea.Cmd
	m.list, cmd = m.list.Update(msg)
	return m, cmd
}

func (m model) View() string {
	if m.choice != "" {
		return quitTextStyle.Render(fmt.Sprintf("%s? Sounds good to me.", m.choice))
	}
	if m.quitting {
		return quitTextStyle.Render("Not hungry? That’s cool.")
	}
	return "\n" + m.list.View()
}

func main() {
	items := []list.Item{
		item("Ramen"),
		item("Tomato Soup"),
		item("Hamburgers"),
		item("Cheeseburgers"),
		item("Currywurst"),
		item("Okonomiyaki"),
		item("Pasta"),
		item("Fillet Mignon"),
		item("Caviar"),
		item("Just Wine"),
	}

	const defaultWidth = 20

	l := list.NewModel(items, itemDelegate{}, defaultWidth, listHeight)
	l.Title = "What do you want for dinner?"
	l.SetShowStatusBar(false)
	l.SetFilteringEnabled(true)
	l.Styles.Title = titleStyle
	l.Styles.PaginationStyle = paginationStyle
	l.Styles.HelpStyle = helpStyle

	m := model{list: l}

	if err := tea.NewProgram(m).Start(); err != nil {
		fmt.Println("Error running program:", err)
		os.Exit(1)
	}
}