blob: 15d7909bd2da7a7966bd8e0094692c95b8666d48 (
plain) (
blame)
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
|
// Copyright 2011 The Walk Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build windows
package walk
type eventHandlerInfo struct {
handler EventHandler
once bool
}
type EventHandler func()
type Event struct {
handlers []eventHandlerInfo
}
func (e *Event) Attach(handler EventHandler) int {
handlerInfo := eventHandlerInfo{handler, false}
for i, h := range e.handlers {
if h.handler == nil {
e.handlers[i] = handlerInfo
return i
}
}
e.handlers = append(e.handlers, handlerInfo)
return len(e.handlers) - 1
}
func (e *Event) Detach(handle int) {
e.handlers[handle].handler = nil
}
func (e *Event) Once(handler EventHandler) {
i := e.Attach(handler)
e.handlers[i].once = true
}
type EventPublisher struct {
event Event
}
func (p *EventPublisher) Event() *Event {
return &p.event
}
func (p *EventPublisher) Publish() {
// This is a kludge to find the form that the event publisher is
// affiliated with. It's only necessary because the event publisher
// doesn't keep a pointer to the form on its own, and the call
// to Publish isn't providing it either.
if form := App().ActiveForm(); form != nil {
fb := form.AsFormBase()
fb.inProgressEventCount++
defer func() {
fb.inProgressEventCount--
if fb.inProgressEventCount == 0 && fb.layoutScheduled {
fb.layoutScheduled = false
fb.startLayout()
}
}()
}
for i, h := range p.event.handlers {
if h.handler != nil {
h.handler()
if h.once {
p.event.Detach(i)
}
}
}
}
|
