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tomo-old/elements/button.go
Sasha Koshka 53f78cb0e7 Overhauled mouse events
Everything gets an image.Point instead of an x y pair, and most
things now get modifiers.
2023-04-20 14:44:54 -04:00

256 lines
6.5 KiB
Go

package elements
import "image"
import "git.tebibyte.media/sashakoshka/tomo"
import "git.tebibyte.media/sashakoshka/tomo/input"
import "git.tebibyte.media/sashakoshka/tomo/canvas"
import "git.tebibyte.media/sashakoshka/tomo/default/theme"
import "git.tebibyte.media/sashakoshka/tomo/default/config"
import "git.tebibyte.media/sashakoshka/tomo/textdraw"
// Button is a clickable button.
type Button struct {
entity tomo.FocusableEntity
drawer textdraw.Drawer
enabled bool
pressed bool
text string
config config.Wrapped
theme theme.Wrapped
showText bool
hasIcon bool
iconId tomo.Icon
onClick func ()
}
// NewButton creates a new button with the specified label text.
func NewButton (text string) (element *Button) {
element = &Button { showText: true, enabled: true }
element.entity = tomo.NewEntity(element).(tomo.FocusableEntity)
element.theme.Case = tomo.C("tomo", "button")
element.drawer.SetFace (element.theme.FontFace (
tomo.FontStyleRegular,
tomo.FontSizeNormal))
element.SetText(text)
return
}
// Entity returns this element's entity.
func (element *Button) Entity () tomo.Entity {
return element.entity
}
// Draw causes the element to draw to the specified destination canvas.
func (element *Button) Draw (destination canvas.Canvas) {
state := element.state()
bounds := element.entity.Bounds()
pattern := element.theme.Pattern(tomo.PatternButton, state)
pattern.Draw(destination, bounds)
foreground := element.theme.Color(tomo.ColorForeground, state)
sink := element.theme.Sink(tomo.PatternButton)
margin := element.theme.Margin(tomo.PatternButton)
offset := image.Pt (
bounds.Dx() / 2,
bounds.Dy() / 2).Add(bounds.Min)
if element.showText {
textBounds := element.drawer.LayoutBounds()
offset.X -= textBounds.Dx() / 2
offset.Y -= textBounds.Dy() / 2
offset.Y -= textBounds.Min.Y
offset.X -= textBounds.Min.X
}
if element.hasIcon {
icon := element.theme.Icon(element.iconId, tomo.IconSizeSmall)
if icon != nil {
iconBounds := icon.Bounds()
addedWidth := iconBounds.Dx()
iconOffset := offset
if element.showText {
addedWidth += margin.X
}
iconOffset.X -= addedWidth / 2
iconOffset.Y =
bounds.Min.Y +
(bounds.Dy() -
iconBounds.Dy()) / 2
if element.pressed {
iconOffset = iconOffset.Add(sink)
}
offset.X += addedWidth / 2
icon.Draw(destination, foreground, iconOffset)
}
}
if element.showText {
if element.pressed {
offset = offset.Add(sink)
}
element.drawer.Draw(destination, foreground, offset)
}
}
// OnClick sets the function to be called when the button is clicked.
func (element *Button) OnClick (callback func ()) {
element.onClick = callback
}
// Focus gives this element input focus.
func (element *Button) Focus () {
if !element.entity.Focused() { element.entity.Focus() }
}
// Enabled returns whether this button is enabled or not.
func (element *Button) Enabled () bool {
return element.enabled
}
// SetEnabled sets whether this button can be clicked or not.
func (element *Button) SetEnabled (enabled bool) {
if element.enabled == enabled { return }
element.enabled = enabled
element.entity.Invalidate()
}
// SetText sets the button's label text.
func (element *Button) SetText (text string) {
if element.text == text { return }
element.text = text
element.drawer.SetText([]rune(text))
element.updateMinimumSize()
element.entity.Invalidate()
}
// SetIcon sets the icon of the button. Passing theme.IconNone removes the
// current icon if it exists.
func (element *Button) SetIcon (id tomo.Icon) {
if id == tomo.IconNone {
element.hasIcon = false
} else {
if element.hasIcon && element.iconId == id { return }
element.hasIcon = true
element.iconId = id
}
element.updateMinimumSize()
element.entity.Invalidate()
}
// ShowText sets whether or not the button's text will be displayed.
func (element *Button) ShowText (showText bool) {
if element.showText == showText { return }
element.showText = showText
element.updateMinimumSize()
element.entity.Invalidate()
}
// SetTheme sets the element's theme.
func (element *Button) SetTheme (new tomo.Theme) {
if new == element.theme.Theme { return }
element.theme.Theme = new
element.drawer.SetFace (element.theme.FontFace (
tomo.FontStyleRegular,
tomo.FontSizeNormal))
element.updateMinimumSize()
element.entity.Invalidate()
}
// SetConfig sets the element's configuration.
func (element *Button) SetConfig (new tomo.Config) {
if new == element.config.Config { return }
element.config.Config = new
element.updateMinimumSize()
element.entity.Invalidate()
}
func (element *Button) HandleFocusChange () {
element.entity.Invalidate()
}
func (element *Button) HandleMouseDown (
position image.Point,
button input.Button,
modifiers input.Modifiers,
) {
if !element.Enabled() { return }
element.Focus()
if button != input.ButtonLeft { return }
element.pressed = true
element.entity.Invalidate()
}
func (element *Button) HandleMouseUp (
position image.Point,
button input.Button,
modifiers input.Modifiers,
) {
if button != input.ButtonLeft { return }
element.pressed = false
within := position.In(element.entity.Bounds())
if element.Enabled() && within && element.onClick != nil {
element.onClick()
}
element.entity.Invalidate()
}
func (element *Button) HandleKeyDown (key input.Key, modifiers input.Modifiers) {
if !element.Enabled() { return }
if key == input.KeyEnter {
element.pressed = true
element.entity.Invalidate()
}
}
func (element *Button) HandleKeyUp(key input.Key, modifiers input.Modifiers) {
if key == input.KeyEnter && element.pressed {
element.pressed = false
element.entity.Invalidate()
if !element.Enabled() { return }
if element.onClick != nil {
element.onClick()
}
}
}
func (element *Button) updateMinimumSize () {
padding := element.theme.Padding(tomo.PatternButton)
margin := element.theme.Margin(tomo.PatternButton)
textBounds := element.drawer.LayoutBounds()
minimumSize := textBounds.Sub(textBounds.Min)
if element.hasIcon {
icon := element.theme.Icon(element.iconId, tomo.IconSizeSmall)
if icon != nil {
bounds := icon.Bounds()
if element.showText {
minimumSize.Max.X += bounds.Dx()
minimumSize.Max.X += margin.X
} else {
minimumSize.Max.X = bounds.Dx()
}
}
}
minimumSize = padding.Inverse().Apply(minimumSize)
element.entity.SetMinimumSize(minimumSize.Dx(), minimumSize.Dy())
}
func (element *Button) state () tomo.State {
return tomo.State {
Disabled: !element.Enabled(),
Focused: element.entity.Focused(),
Pressed: element.pressed,
}
}