andlabs-ui/button.go

78 lines
1.5 KiB
Go

// 12 february 2014
package ui
import (
"sync"
)
// A Button represents a clickable button with some text.
type Button struct {
// This channel gets a message when the button is clicked. Unlike other channels in this package, this channel is initialized to non-nil when creating a new button, and cannot be set to nil later.
Clicked chan struct{}
lock sync.Mutex
created bool
sysData *sysData
initText string
}
// NewButton creates a new button with the specified text.
func NewButton(text string) (b *Button) {
return &Button{
sysData: mksysdata(c_button),
initText: text,
Clicked: Event(),
}
}
// SetText sets the button's text.
func (b *Button) SetText(text string) (err error) {
b.lock.Lock()
defer b.lock.Unlock()
if b.created {
return b.sysData.setText(text)
}
b.initText = text
return nil
}
// Text returns the button's text.
func (b *Button) Text() string {
b.lock.Lock()
defer b.lock.Unlock()
if b.created {
return b.sysData.text()
}
return b.initText
}
func (b *Button) make(window *sysData) error {
b.lock.Lock()
defer b.lock.Unlock()
b.sysData.event = b.Clicked
err := b.sysData.make(b.initText, window)
if err != nil {
return err
}
b.created = true
return nil
}
func (b *Button) setRect(x int, y int, width int, height int) error {
b.lock.Lock()
defer b.lock.Unlock()
return b.sysData.setRect(x, y, width, height)
}
func (b *Button) preferredSize() (width int, height int, err error) {
b.lock.Lock()
defer b.lock.Unlock()
width, height = b.sysData.preferredSize()
return
}