Add input components 066-085; gallery chrome on real components; deploy warms the edge

input/textarea.go

@@ -0,0 +1,67 @@
+package input
+
+import (
+	"fmt"
+	"unicode/utf8"
+
+	"github.com/egoist/mygo/ui"
+
+	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/pixel"
+)
+
+type TextAreaOptions struct {
+	Placeholder string
+	// MaxLength caps runes and shows a count.
+	MaxLength int
+	// Width is zero for 160 dots, Lines zero for 4.
+	Width, Lines int
+	Disabled     bool
+}
+
+type areaKey struct{}
+
+type areaState struct {
+	scroll ui.ScrollState
+	line   int
+	text   string
+	// held is last frame's offset, kept while disabled.
+	held float32
+}
+
+type TextAreaResult = TextInputResult
+
+// TextArea wraps lines in its own scroll, following the caret.
+func TextArea(c *ui.Context, text string, value *string, o TextAreaOptions) TextAreaResult {
+	k := pixel.K(c)
+	lines := orDef("TextArea Lines", o.Lines, 4)
+	col := ui.Column(c).Width(k.D(orDef("TextArea Width", o.Width, 160))).Gap(k.D(2))
+	st := ui.Local(col, areaKey{}, func() areaState { return areaState{line: -1} })
+	if o.Disabled {
+		st.scroll.Y = st.held
+	}
+	var ed pixel.Edit
+	col.Children(func() {
+		view := ui.Scroll(c).TrackScroll(&st.scroll).Height(k.D(lines*pixel.LineHeight+6)).Padding(k.D(3), k.D(4))
+		view.Draw(func(p *ui.Painter, r ui.Rect) {
+			g := k.Canvas(p, r)
+			g.Frame(0, 0, g.W, g.H, pixel.Sunken, pixel.Well)
+		}).Children(func() {
+			ed = pixel.Editor(c, value, pixel.EditorOptions{Multiline: true, Label: text, Placeholder: o.Placeholder, MaxLength: o.MaxLength, Disabled: o.Disabled})
+		})
+		// Keep the caret's line in view after it moves.
+		if ed.Line != st.line || *value != st.text {
+			top, bottom := k.D(ed.Line*pixel.LineHeight), k.D((ed.Line+1)*pixel.LineHeight)
+			if y := max(min(st.scroll.Y, top), bottom-k.D(lines*pixel.LineHeight)); y != st.scroll.Y {
+				st.scroll.Y = y
+				view.TrackScroll(&st.scroll)
+			}
+			st.line, st.text = ed.Line, *value
+		}
+		st.held = st.scroll.Y
+		if o.MaxLength > 0 {
+			count := fmt.Sprintf("%d/%d", utf8.RuneCountInString(*value), o.MaxLength)
+			ui.Row(c).Justify(ui.End).Children(func() { pixel.Text(c, count, pixel.TextOptions{Slot: pixel.Faint}) })
+		}
+	})
+	return result(col, ed, text)
+}