erm/vendor/github.com/lxn/walk/closeevent.go

63 lines
1.2 KiB
Go

// 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 closeEventHandlerInfo struct {
handler CloseEventHandler
once bool
}
type CloseEventHandler func(canceled *bool, reason CloseReason)
type CloseEvent struct {
handlers []closeEventHandlerInfo
}
func (e *CloseEvent) Attach(handler CloseEventHandler) int {
handlerInfo := closeEventHandlerInfo{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 *CloseEvent) Detach(handle int) {
e.handlers[handle].handler = nil
}
func (e *CloseEvent) Once(handler CloseEventHandler) {
i := e.Attach(handler)
e.handlers[i].once = true
}
type CloseEventPublisher struct {
event CloseEvent
}
func (p *CloseEventPublisher) Event() *CloseEvent {
return &p.event
}
func (p *CloseEventPublisher) Publish(canceled *bool, reason CloseReason) {
for i, h := range p.event.handlers {
if h.handler != nil {
h.handler(canceled, reason)
if h.once {
p.event.Detach(i)
}
}
}
}