package ui import ( "sync/atomic" "github.com/gdamore/tcell" ) type UI struct { Content DrawableInteractive exit atomic.Value // bool ctx *Context screen tcell.Screen popover *Popover tcEvents chan tcell.Event invalid int32 // access via atomic } func Initialize(content DrawableInteractiveBeeper) (*UI, error) { screen, err := tcell.NewScreen() if err != nil { return nil, err } if err = screen.Init(); err != nil { return nil, err } screen.Clear() screen.HideCursor() width, height := screen.Size() state := UI{ Content: content, screen: screen, tcEvents: make(chan tcell.Event, 10), } state.ctx = NewContext(width, height, screen, state.onPopover) state.exit.Store(false) go func() { for !state.ShouldExit() { state.tcEvents <- screen.PollEvent() } }() state.invalid = 1 content.OnInvalidate(func(_ Drawable) { atomic.StoreInt32(&state.invalid, 1) }) content.OnBeep(screen.Beep) content.Focus(true) if root, ok := content.(RootDrawable); ok { root.Initialize(&state) } return &state, nil } func (state *UI) onPopover(p *Popover) { state.popover = p } func (state *UI) ShouldExit() bool { return state.exit.Load().(bool) } func (state *UI) Exit() { state.exit.Store(true) } func (state *UI) Close() { state.screen.Fini() } func (state *UI) Tick() bool { more := false select { case event := <-state.tcEvents: switch event := event.(type) { case *tcell.EventResize: state.screen.Clear() width, height := event.Size() state.ctx = NewContext(width, height, state.screen, state.onPopover) state.Content.Invalidate() } // if we have a popover, and it can handle the event, it does so if state.popover == nil || !state.popover.Event(event) { // otherwise, we send the event to the main content state.Content.Event(event) } more = true default: } wasInvalid := atomic.SwapInt32(&state.invalid, 0) if wasInvalid != 0 { if state.popover != nil { // if the previous frame had a popover, rerender the entire display state.Content.Invalidate() atomic.StoreInt32(&state.invalid, 0) } // reset popover for the next Draw state.popover = nil state.Content.Draw(state.ctx) if state.popover != nil { // if the Draw resulted in a popover, draw it state.popover.Draw(state.ctx) } state.screen.Show() more = true } return more } func (state *UI) EnableMouse() { state.screen.EnableMouse() }