App Structure¶

The Component Interface¶

Every blit widget implements Component:

type Component interface {
    Init() tea.Cmd
    Update(msg tea.Msg, ctx Context) (Component, tea.Cmd)
    View() string
    KeyBindings() []KeyBind
    SetSize(w, h int)
    Focused() bool
    SetFocused(bool)
}

Components that support theming also implement Themed:

type Themed interface {
    SetTheme(Theme)
}

The App calls SetTheme on all registered components automatically when the theme changes.

Key Dispatch Order¶

When a key arrives the App dispatches it in this order:

Overlay stack (e.g. Help, ConfigEditor, Picker)
Built-in globals: q quit, tab cycle focus, ? help
Pane toggle key (DualPane)
Overlay trigger keys registered with WithOverlay
App-level keybindings registered with WithKeyBind
Focused component's Update

Return blit.Consumed() from Update to stop further dispatch.

Slots¶

The App organises components into named slots:

Slot	Description
`SlotMain`	Primary content pane
`SlotSidebar`	Side panel (DualPane only)
`SlotFooter`	StatusBar

WithComponent fills SlotMain. WithLayout maps DualPane.Main → SlotMain and DualPane.Side → SlotSidebar.

Registering Keybindings¶

blit.WithKeyBind(blit.KeyBind{
    Key:   "r",
    Label: "Refresh",
    Group: "DATA",
    Handler: func() {
        table.SetRows(fetchRows())
    },
})

All registered bindings appear in the auto-generated Help overlay.

Pushing Data from Goroutines¶

app := blit.NewApp(...)
go func() {
    for data := range stream {
        app.Send(MyDataMsg{data})
    }
}()
app.Run()

Unknown message types are forwarded to all components via Update.