zntg/ui/control.go

package ui

import (
	"time"

	"opslag.de/schobers/zntg/allg5"
	"opslag.de/schobers/geom"
)

type Control interface {
	Created(Context, Container) error
	Destroyed(Context)

	Update(Context, time.Duration)
	Handle(Context, allg5.Event)
	DesiredSize(Context) geom.PointF
	Rect() geom.RectangleF
	SetRect(geom.RectangleF)
	Render(Context)
}

type MouseClickFn func(Control)

var _ Control = &ControlBase{}

type ControlBase struct {
	Parent     Container
	Bounds     geom.RectangleF
	Disabled   bool
	IsOver     bool
	IsPressed  bool
	OnClick    MouseClickFn
	MinSize    geom.PointF
	Background *allg5.Color
}

func (c *ControlBase) Created(_ Context, p Container) error {
	c.Parent = p
	return nil
}

func (c *ControlBase) Destroyed(Context) {}

func (c *ControlBase) Update(Context, time.Duration) {}

func (c *ControlBase) Handle(ctx Context, ev allg5.Event) {
	switch e := ev.(type) {
	case *allg5.MouseMoveEvent:
		c.IsOver = c.IsInRect(float64(e.X), float64(e.Y))
	case *allg5.MouseButtonDownEvent:
		if c.IsOver {
			c.IsPressed = true
		}
	case *allg5.MouseButtonUpEvent:
		if c.IsPressed && c.IsOver {
			var onClick = c.OnClick
			if nil != onClick {
				onClick(c)
			}
		}
		c.IsPressed = false
	}
}

func (c *ControlBase) DesiredSize(Context) geom.PointF {
	return c.MinSize
}

func (c *ControlBase) SetRect(rect geom.RectangleF) {
	c.Bounds = rect
}

func (c *ControlBase) Render(ctx Context) {
	var min = c.Bounds.Min.To32()
	var max = c.Bounds.Max.To32()
	if nil != c.Background {
		allg5.DrawFilledRectangle(min.X, min.Y, max.X, max.Y, *c.Background)
	}
	if ctx.Debug().IsEnabled() {
		allg5.DrawRectangle(min.X, min.Y, max.X, max.Y, ctx.Debug().Rainbow(), 5)
	}
}

func (c *ControlBase) Rect() geom.RectangleF {
	return c.Bounds
}

func (c *ControlBase) IsInRect(x, y float64) bool {
	return geom.PtF(x, y).In(c.Bounds)
}