objects/checkbox.go

package objects

import "git.tebibyte.media/tomo/tomo"
import "git.tebibyte.media/tomo/tomo/input"
import "git.tebibyte.media/tomo/tomo/event"

// Checkbox is a control that can be toggled.
type Checkbox struct {
	tomo.Box
	value bool
	on struct {
		valueChange event.FuncBroadcaster
	}
}

// NewCheckbox creates a new checkbox with the specified value.
func NewCheckbox (value bool) *Checkbox {
	box := &Checkbox {
		Box: tomo.NewBox(),
	}
	box.SetRole(tomo.R("objects", "Checkbox", ""))
	box.SetValue(value)
	
	box.OnMouseUp(box.handleMouseUp)
	box.OnKeyUp(box.handleKeyUp)
	box.SetFocusable(true)
	return box
}

// SetValue sets the value of the checkbox.
func (this *Checkbox) SetValue (value bool) {
	this.value = value
	if this.value {
		this.SetTextureCenter(tomo.IconCheckboxChecked.Texture(tomo.IconSizeSmall))
	} else {
		this.SetTextureCenter(tomo.IconCheckboxUnchecked.Texture(tomo.IconSizeSmall))
	}
}

// Toggle toggles the value of the checkbox between true and false.
func (this *Checkbox) Toggle () {
	this.SetValue(!this.Value())
}

// Value returns the value of the checkbox.
func (this *Checkbox) Value () bool {
	return this.value
}

// OnValueChange specifies a function to be called when the checkbox's value
// changes.
func (this *Checkbox) OnValueChange (callback func ()) event.Cookie {
	return this.on.valueChange.Connect(callback)
}

func (this *Checkbox) handleKeyUp (key input.Key, numberPad bool) {
	if key != input.KeyEnter && key != input.Key(' ') { return }
	this.Toggle()
}

func (this *Checkbox) handleMouseUp (button input.Button) {
	if button != input.ButtonLeft { return }
	if this.MousePosition().In(this.Bounds()) {
		this.Toggle()
	}
}