tomo/theme/theme.go

89 lines
2.7 KiB
Go

package theme
import "git.tebibyte.media/tomo/tomo"
import "git.tebibyte.media/tomo/tomo/data"
import "git.tebibyte.media/tomo/tomo/event"
import "git.tebibyte.media/tomo/tomo/canvas"
// Role describes the role of an object.
type Role struct {
// Package is an optional namespace field. If specified, it should be
// the package name or module name the object is from.
Package string
// Object specifies what type of object it is. For example:
// - TextInput
// - Table
// - Label
// - Dial
// This should correspond directly to the type name of the object.
Object string
// Variant is an optional field to be used when an object has one or
// more soft variants under one type. For example, an object "Slider"
// may have variations "horizontal" and "vertical".
Variant string
}
// R is shorthand for creating a Role structure.
func R (pack, object, variant string) Role {
return Role { Package: pack, Object: object, Variant: variant }
}
// Color represents a color ID.
type Color int; const (
ColorBackground Color = iota
ColorForeground
ColorRaised
ColorSunken
ColorAccent
)
// RGBA satisfies the color.Color interface.
func (id Color) RGBA () (r, g, b, a uint32) {
if current == nil { return }
return current.RGBA(id)
}
// Theme is an object that can apply a visual style to different objects.
type Theme interface {
// Apply applies the theme to the given object, according to the given
// role. This may register event listeners with the given object;
// closing the returned cookie will remove them.
Apply (tomo.Object, Role) event.Cookie
// RGBA returns the RGBA values of the corresponding color ID.
RGBA (Color) (r, g, b, a uint32)
// Icon returns a texture of the corresponding icon ID. This texture
// should be protected, unless a new copy of it is returned with each
// subsequent call.
Icon (Icon, IconSize) canvas.Texture
// MimeIcon returns an icon corresponding to a MIME type. This texture
// should be protected, unless a new copy of it is returned with each
// subsequent call.
MimeIcon (data.Mime, IconSize) canvas.Texture
// ApplicationIcon returns an icon corresponding to an application. This
// texture should be protected, unless a new copy of it is returned with
// each subsequent call.
ApplicationIcon (ApplicationIcon, IconSize) canvas.Texture
}
var current Theme
// SetTheme sets the theme.
func SetTheme (theme Theme) {
current = theme
}
// Apply applies the current theme to the given object, according to the given
// role. This may register event listeners with the given object; closing the
// returned cookie will remove them.
func Apply (object tomo.Object, role Role) event.Cookie {
if current == nil { return event.NoCookie { } }
return current.Apply(object, role)
}