Cannot get the input value when using textinput

[josark2005]

Code:

package tui

// A simple program demonstrating the text input component from the Bubbles
// component library.

import (
	"fmt"
	"log"

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

type errMsg error

type model struct {
	textInput textinput.Model
	err       error
}

var inputPlaceholder string

func initialModel() model {
	ti := textinput.New()
	ti.Placeholder = inputPlaceholder
	ti.Focus()
	ti.CharLimit = 156
	ti.Width = 20

	return model{
		textInput: ti,
		err:       nil,
	}
}

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

func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
	var cmd tea.Cmd

	switch msg := msg.(type) {
	case tea.KeyMsg:
		switch msg.Type {
		case tea.KeyEnter, tea.KeyCtrlC, tea.KeyEsc:
			fmt.Println(m)
			return m, tea.Quit
		}

	// We handle errors just like any other message
	case errMsg:
		m.err = msg
		return m, nil
	}

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

var inputTitle string

func (m model) View() string {
	return fmt.Sprintf(
		inputTitle+"\n\n%s\n\n%s",
		m.textInput.View(),
		"(esc to quit)",
	) + "\n"
}

func Input(title string, placeholder string) string {
	inputTitle = title
	inputPlaceholder = placeholder
	m := initialModel()
	p := tea.NewProgram(m)
	if err := p.Start(); err != nil {
		log.Fatal(err)
	}
	fmt.Println()
	fmt.Println("value:", m.textInput.Value())
	return m.textInput.Value()
}

Console messages:

{{<nil> >  placeholder 530000000 0 42 {map[] } {map[] } {map[] } {map[7:240] } {map[] } 156 20 1 5 [49 50 51] true false 3 0 3 0xc000004168 0} <nil>}

value:

I am confused that why the value is not updated finally?

[muesli]

At a first glance your code probably works fine, but after p.Start you're retrieving the input from the initial model, which will always remain empty: it gets replaced by a new model every time Update gets called. You can either let Update operate on a pointer-receiver, so you keep modifying your original model, or implement another way to store the final value before calling tea.Quit.

[josark2005]

I changed the lines blow:

func (m *model) Update(msg tea.Msg) (tea.Model, tea.Cmd)

p := tea.NewProgram(&m)

It works fine, thank you very much.

[aureq]

I think it would be very valuable for the community to have these 2 lines integrated into the 2 input examples as part of this repository.

[josark2005]

For new hands of golang, it is.

[aureq]

Yes totally. We all should strive to be more inclusive, including with people who are just discovering Golang or anything else.