使用Bubbles开发Golang终端用户界面(TUI)

Bubbles是Bubble Tea框架中的一个组件库，用于构建丰富的终端用户界面(TUI)。Bubble Tea是一个基于Elm架构的Go框架，专门用于创建终端应用程序。

安装Bubble Tea

首先需要安装Bubble Tea框架：

go get github.com/charmbracelet/bubbletea

Bubbles基础组件

Bubbles提供了多种常用组件，下面介绍几个核心组件：

1. Text Input组件

package main

import (
	"fmt"
	"os"

	"github.com/charmbracelet/bubbles/textinput"
	tea "github.com/charmbracelet/bubbletea"
)

type model struct {
	textInput textinput.Model
}

func initialModel() model {
	ti := textinput.New()
	ti.Placeholder = "输入你的名字..."
	ti.Focus()
	ti.CharLimit = 156
	ti.Width = 20

	return model{
		textInput: ti,
	}
}

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.KeyMsg:
		switch msg.Type {
		case tea.KeyEnter:
			return m, tea.Quit
		case tea.KeyCtrlC, tea.KeyEsc:
			return m, tea.Quit
		}
	}

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

func (m model) View() string {
	return fmt.Sprintf(
		"请输入:\n\n%s\n\n(按Enter提交)",
		m.textInput.View(),
	)
}

func main() {
	p := tea.NewProgram(initialModel())
	if _, err := p.Run(); err != nil {
		fmt.Printf("出错了: %v", err)
		os.Exit(1)
	}
}

2. List组件

package main

import (
	"fmt"
	"os"

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

type item string

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

type model struct {
	list list.Model
}

func initialModel() model {
	items := []list.Item{
		item("选项1"),
		item("选项2"),
		item("选项3"),
	}

	l := list.New(items, list.NewDefaultDelegate(), 0, 0)
	l.Title = "选择菜单"

	return model{list: l}
}

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.KeyMsg:
		switch msg.String() {
		case "ctrl+c", "q":
			return m, tea.Quit
		case "enter":
			selected := m.list.SelectedItem().(item)
			fmt.Printf("你选择了: %s\n", selected)
			return m, tea.Quit
		}
	}

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

func (m model) View() string {
	return m.list.View()
}

func main() {
	p := tea.NewProgram(initialModel())
	if _, err := p.Run(); err != nil {
		fmt.Printf("出错了: %v", err)
		os.Exit(1)
	}
}

3. Spinner组件

package main

import (
	"fmt"
	"os"
	"time"

	"github.com/charmbracelet/bubbles/spinner"
	tea "github.com/charmbracelet/bubbletea"
)

type model struct {
	spinner  spinner.Model
	quitting bool
}

func initialModel() model {
	s := spinner.New()
	s.Spinner = spinner.Dot
	s.Style = spinner.WithStyle("bold green")

	return model{spinner: s}
}

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

func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
	switch msg := msg.(type) {
	case tea.KeyMsg:
		switch msg.String() {
		case "q", "esc", "ctrl+c":
			m.quitting = true
			return m, tea.Quit
		}
	case spinner.TickMsg:
		var cmd tea.Cmd
		m.spinner, cmd = m.spinner.Update(msg)
		return m, cmd
	}

	return m, nil
}

func (m model) View() string {
	if m.quitting {
		return "任务完成!\n"
	}
	return fmt.Sprintf("\n   %s 加载中... 按q退出\n\n", m.spinner.View())
}

func main() {
	p := tea.NewProgram(initialModel())
	if _, err := p.Run(); err != nil {
		fmt.Println("出错了:", err)
		os.Exit(1)
	}
}

组合多个组件

Bubbles的强大之处在于可以组合多个组件创建复杂界面：

package main

import (
	"fmt"
	"os"

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

type model struct {
	list      list.Model
	textInput textinput.Model
	focused   string // 当前焦点组件
}

const (
	listView = "list"
	inputView = "input"
)

func initialModel() model {
	// 初始化列表
	items := []list.Item{
		item("选项1"),
		item("选项2"),
		item("选项3"),
	}
	l := list.New(items, list.NewDefaultDelegate(), 0, 0)
	l.Title = "主菜单"

	// 初始化输入框
	ti := textinput.New()
	ti.Placeholder = "输入搜索内容..."
	ti.Width = 30

	return model{
		list:      l,
		textInput: ti,
		focused:   listView,
	}
}

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.KeyMsg:
		switch msg.String() {
		case "ctrl+c", "q":
			return m, tea.Quit
		case "tab":
			if m.focused == listView {
				m.focused = inputView
				return m, textinput.Blink
			} else {
				m.focused = listView
			}
		}
	}

	var cmd tea.Cmd
	if m.focused == listView {
		m.list, cmd = m.list.Update(msg)
	} else {
		m.textInput, cmd = m.textInput.Update(msg)
	}
	return m, cmd
}

func (m model) View() string {
	return fmt.Sprintf(
		"%s\n\n%s\n\n按tab切换焦点, q退出",
		m.list.View(),
		m.textInput.View(),
	)
}

func main() {
	p := tea.NewProgram(initialModel())
	if _, err := p.Run(); err != nil {
		fmt.Printf("出错了: %v", err)
		os.Exit(1)
	}
}

自定义样式

Bubbles组件支持丰富的样式定制：

package main

import (
	"fmt"
	"os"

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

var (
	titleStyle = lipgloss.NewStyle().
			Foreground(lipgloss.Color("#FFFDF5")).
			Background(lipgloss.Color("#25A065")).
			Padding(0, 1)

	itemStyle = lipgloss.NewStyle().PaddingLeft(2)
	selectedItemStyle = lipgloss.NewStyle().
				PaddingLeft(1).
				Foreground(lipgloss.Color("170"))
)

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 lipgloss.Window, 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.Fprint(w, fn(str))
}

func main() {
	items := []list.Item{
		item("红色"),
		item("绿色"),
		item("蓝色"),
	}

	l := list.New(items, itemDelegate{}, 20, 10)
	l.Title = titleStyle.Render("颜色选择")
	l.Styles.Title = titleStyle

	m := model{list: l}
	p := tea.NewProgram(m, tea.WithAltScreen())
	if _, err := p.Run(); err != nil {
		fmt.Println("出错了:", err)
		os.Exit(1)
	}
}

type model struct {
	list list.Model
}

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.KeyMsg:
		switch msg.String() {
		case "ctrl+c", "q":
			return m, tea.Quit
		}
	}

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

func (m model) View() string {
	return m.list.View()
}

总结

Bubbles为Golang提供了强大的TUI开发能力，主要特点包括：

1. 丰富的内置组件：文本框、列表、进度条、表格等
2. 响应式设计：基于Elm架构，状态管理清晰
3. 高度可定制：样式、布局均可自定义
4. 组件组合：可以轻松组合多个组件创建复杂界面
5. 跨平台支持：兼容各种终端环境

通过Bubble Tea和Bubbles，开发者可以快速构建现代化、用户友好的命令行工具。