nanoui.go

package nanoui

import (
	"go.awoo.fun/of/pkg/nanovg"
)

// Handler is executed whenever an event occours, use type-switching to get the exact event you want.
type Handler interface {
	Handle(interface{}) error
}

// Drawer handles the drawing of the elements and is called every frame.
type Drawer interface {
	Draw(bounds []int, ctx *nanovg.Context)
}

// Component is a combination of Handler and a Drawer.
type Component interface {
	Handler
	Drawer
}

// Layouter handles calculating layout for given component in a container.
type Layouter interface {
	Layout(container Components, element int) (bounds []int)
}

// Styler returns value for given styleset & property combination.
type Styler interface {
	Style(styleset, property string) (value interface{}, ok bool)
}

// NewDesigner returns a new Designer for building GUI layouts.
func NewDesigner(style Styler) Designer {
	return nil // TODO
}

// Designer provides methods for laying out a series of Components.
type Designer interface {
	Components

	// Design finalizes the component tree and returns root Components.
	Design() Components

	// AddHandlers adds inline event handlers for current group.
	AddHandlers(...Handler)

	// AddDrawers adds inline drawers for current group.
	AddDrawers(...Drawer)

	// AddComponents adds Components to the current group.
	AddComponents(...Component)

	// With adds a new layer with optionally custom Layouter.
	// If empty inherits parent's Layouter.
	With(Layouter, func(d Designer))
}

// Components is a container of all the Components...
type Components interface {
	Component

	// Root returns the base container, likely to have NVGContext.
	Root() Components

	// Parent returns the parent container.
	Parent() Components

	// Layout returns the Layouter for this container.
	Layout() Layouter

	// Components returns list of Components this container has.
	Components() []Components
}