Add data components 151-175; clear MyGo row highlights

Lists, tables, trees, grids, inventories and records in data/.
Outline and GridView build on ui.List: ui.Outline strokes its arrows
and ui.GridView spaces and tints items. The pixel theme keeps MyGo's
row highlights clear so scrolled rows stay on whole dots; off lists
take a veil against the wheel. Adds Canvas.Silhouette, SwitchOptions
Label and exports Rarity.Slot.

data/gridview.go

@@ -0,0 +1,110 @@
+package data
+
+import (
+	"log/slog"
+	"strconv"
+
+	"github.com/egoist/mygo/ui"
+
+	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/pixel"
+)
+
+type GridViewOptions struct {
+	// CellWidth and CellHeight are each item's dots; zeros mean 48.
+	CellWidth, CellHeight int
+	// Height is the view's in dots; zero means 140.
+	Height   int
+	Disabled bool
+}
+
+type GridViewResult struct {
+	Element *ui.Element
+	// Submitted is Enter or a double click on an item.
+	Changed, Submitted bool
+}
+
+type gridKey struct{}
+
+// grid holds the rows' place and clicks met during layout.
+type grid struct {
+	rows            ui.ListState
+	clicked, double bool
+}
+
+// GridView is a virtual grid framing its chosen item.
+func GridView(c *ui.Context, text string, n int, selected *int, o GridViewOptions, item func(i int)) GridViewResult {
+	k := pixel.K(c)
+	off := o.Disabled || pixel.Current(c).Inert
+	cw, ch := pixel.Or("GridView CellWidth", o.CellWidth, 48), pixel.Or("GridView CellHeight", o.CellHeight, 48)
+	box := ui.Box(c).FillWidth().Role(ui.RoleGroup).Label(text)
+	if !off {
+		box.Focusable()
+	}
+	pixel.Park(c, box, off)
+	s := ui.Local(box, gridKey{}, func() grid { return grid{} })
+	res := GridViewResult{Element: box, Changed: s.clicked, Submitted: s.double}
+	s.clicked, s.double = false, false
+	cols := 1
+	box.Children(func() {
+		holder := ui.Box(c).FillWidth()
+		w, check := pixel.WrapWidth(c, holder)
+		cols = max(1, w/cw)
+		holder.Draw(func(p *ui.Painter, r ui.Rect) { check(r) }).Children(func() {
+			ui.List(c, &s.rows, (n+cols-1)/cols, pixel.Lazy(c, func(r int) {
+				ui.Row(c).Children(func() {
+					for i := r * cols; i < min(n, (r+1)*cols); i++ {
+						cell := ui.Box(c).Size(k.D(cw), k.D(ch))
+						if !off && cell.Clicked() {
+							*selected, s.clicked = i, true
+							box.Focus()
+							c.Invalidate()
+						}
+						if !off && cell.DoubleClicked() {
+							s.double = true
+						}
+						on := i == *selected
+						cell.Draw(func(p *ui.Painter, r ui.Rect) {
+							if on {
+								g := k.Canvas(p, r)
+								g.Rect(0, 0, g.W, 2, pixel.Accent)
+								g.Rect(0, g.H-2, g.W, 2, pixel.Accent)
+								g.Rect(0, 0, 2, g.H, pixel.Accent)
+								g.Rect(g.W-2, 0, 2, g.H, pixel.Accent)
+							}
+						}).Children(func() { item(i) })
+					}
+				})
+			})).Width(k.D(cols * cw)).Height(k.D(pixel.Or("GridView Height", o.Height, 140)))
+		})
+		veil(c, off)
+	})
+	old := *selected
+	for _, m := range []struct {
+		key ui.Key
+		to  int
+	}{
+		{ui.KeyLeft, old - 1}, {ui.KeyRight, old + 1}, {ui.KeyUp, old - cols}, {ui.KeyDown, old + cols},
+		{ui.KeyHome, 0}, {ui.KeyEnd, n - 1},
+	} {
+		if box.Shortcut(0, m.key) && m.to >= 0 && m.to < n {
+			*selected = m.to
+		}
+	}
+	if *selected != old {
+		res.Changed = true
+		s.rows.ScrollIntoView(*selected / cols)
+	}
+	if box.Shortcut(0, ui.KeyEnter) {
+		res.Submitted = true
+	}
+	if off {
+		box.Description(k.Msg("disabled"))
+	} else if *selected >= 0 {
+		box.Description(strconv.Itoa(*selected+1) + "/" + strconv.Itoa(n))
+	}
+	well(c, box, pixel.State{Focus: box.FocusRing(false).FocusVisible(), Disabled: o.Disabled})
+	if res.Changed || res.Submitted {
+		slog.Debug("8bit: grid view", "label", text, "selected", *selected, "submitted", res.Submitted)
+	}
+	return res
+}