1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
|
package ui
import (
"sync/atomic"
"github.com/gdamore/tcell/v2"
)
// Use unbuffered channels (always blocking unless somebody can read
// immediately) We are merely using this as a proxy to tcell screen internal
// event channel.
var Events = make(chan tcell.Event)
var Quit = make(chan struct{})
var Callbacks = make(chan func(), 50)
// QueueFunc queues a function to be called in the main goroutine. This can be
// used to prevent race conditions from delayed functions
func QueueFunc(fn func()) {
Callbacks <- fn
}
// Use a buffered channel of size 1 to avoid blocking callers of Invalidate()
var Redraw = make(chan bool, 1)
// Invalidate marks the entire UI as invalid and request a redraw as soon as
// possible. Invalidate can be called from any goroutine and will never block.
func Invalidate() {
if atomic.SwapUint32(&state.dirty, 1) != 1 {
Redraw <- true
}
}
var state struct {
content DrawableInteractive
ctx *Context
screen tcell.Screen
popover *Popover
dirty uint32 // == 1 if render has been queued in Redraw channel
}
func Initialize(content DrawableInteractive) error {
screen, err := tcell.NewScreen()
if err != nil {
return err
}
if err = screen.Init(); err != nil {
return err
}
screen.Clear()
screen.HideCursor()
screen.EnablePaste()
width, height := screen.Size()
state.content = content
state.screen = screen
state.ctx = NewContext(width, height, state.screen, onPopover)
Invalidate()
if beeper, ok := content.(DrawableInteractiveBeeper); ok {
beeper.OnBeep(screen.Beep)
}
content.Focus(true)
go state.screen.ChannelEvents(Events, Quit)
return nil
}
func onPopover(p *Popover) {
state.popover = p
}
func Exit() {
close(Quit)
}
func Close() {
state.screen.Fini()
}
func Render() {
if atomic.SwapUint32(&state.dirty, 0) != 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()
}
}
func EnableMouse() {
state.screen.EnableMouse()
}
func HandleEvent(event tcell.Event) {
if event, ok := event.(*tcell.EventResize); ok {
state.screen.Clear()
width, height := event.Size()
state.ctx = NewContext(width, height, state.screen, onPopover)
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)
}
}
|