Screen, size, and colors in Bubble Tea v2

The less common tea.View fields, full window layouts, and light or dark background detection. Return to the main skill for the core tea.View fields; api.md has the field table.

Other tea.View fields

BackgroundColor, ForegroundColor (terminal colors, nil resets), ProgressBar (native terminal progress, where supported), DisableBracketedPasteMode, KeyboardEnhancements (ask for key release events), OnMouse (intercept mouse messages against the last render), and ProgramStatus (an OSC 7501 report of idle, working, blocked, done, or failed for terminals that support it; it is not cleared on exit, so report done or error before quitting).

Window size and full screen

tea.WindowSizeMsg arrives once at start and again on every resize. Store Width and Height and use them in View (examples/charmed-bubbletea/fullscreen/main.go):

// examples/charmed-bubbletea/fullscreen/main.go
case tea.WindowSizeMsg:
    m.width, m.height = msg.Width, msg.Height

func (m model) View() tea.View {
    box := lipgloss.NewStyle().Border(lipgloss.RoundedBorder()).Padding(1, 3).
        Render(fmt.Sprintf("terminal is %d x %d\npress q to quit", m.width, m.height))
    v := tea.NewView(lipgloss.Place(m.width, m.height, lipgloss.Center, lipgloss.Center, box))
    v.AltScreen = true
    v.WindowTitle = "fullscreen example"
    return v
}

Light and dark backgrounds

Bubble Tea downsamples colors to the terminal's profile on output, so styles may use true color. What it cannot guess is whether the background is light or dark; ask for it (examples/charmed-bubbletea/adaptive/main.go):

// examples/charmed-bubbletea/adaptive/main.go
func newModel() model {
    // Start with a guess so the first frame is already styled; the reply
    // (if one comes) replaces it.
    return model{styles: newStyles(true), isDark: true}
}

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

case tea.BackgroundColorMsg:
    m.isDark, m.detected = msg.IsDark(), true
    m.styles = newStyles(m.isDark)

func newStyles(isDark bool) styles {
    ld := lipgloss.LightDark(isDark)
    return styles{
        title: lipgloss.NewStyle().Bold(true).
            Foreground(ld(lipgloss.Color("#5A2D82"), lipgloss.Color("#C4A7F5"))),
    }
}

Render the real UI from the first frame with a default guess; some terminals never reply, and a "detecting..." placeholder would then stay up forever. Most Bubbles style constructors take the same bool (see charmed-bubbles for the two that do not).