Chat Messages: components 201-220

scroll_to_bottom_button.go

@@ -0,0 +1,47 @@
+package mujica
+
+import (
+	"fmt"
+
+	"github.com/egoist/mygo/ui"
+
+	"mujicaui/icons"
+	"mujicaui/internal"
+	"mujicaui/theme"
+)
+
+// ScrollToBottomButton shows while away is true, with the unread count; click it to return to the end.
+// While hidden it returns an empty element whose Clicked is false.
+func ScrollToBottomButton(c *ui.Context, away bool, unread int) *ui.Element {
+	if unread < 0 {
+		panic("mujica: ScrollToBottomButton unread must not be negative")
+	}
+	if !away {
+		return ui.Box(c).Absolute().Invisible()
+	}
+	k := Tokens(c)
+	u := Density(c).Unit()
+	label := msg(c, "scroll_to_bottom_button.label")
+	if unread > 0 {
+		label = fmt.Sprintf(msg(c, "scroll_to_bottom_button.unread"), unread)
+	}
+	wrap := ui.Row(c).Absolute().Left(0).Right(0).Bottom(u * 3).Justify(ui.Center).PassThrough()
+	var b *ui.Element
+	wrap.Children(func() {
+		b = ui.ButtonBase(c).MinHeight(theme.MinHitSize).MinWidth(theme.MinHitSize).Padding(0, u*3).Gap(u*2).
+			Radius(theme.MinHitSize/2).Label(label).Background(k.Surface).Border(theme.BorderWidth, k.ControlBorder).
+			TextColor(k.Text).Shadow(0, 2, 8, 0, ui.RGBA(0, 0, 0, 0.14)).Transition(colorFade)
+		b.Opacity(overlayEnter(c, b))
+		internal.Ring(b, k.Focus, theme.MinHitSize/2)
+		if b.Hovered() {
+			b.Background(k.SurfaceHover)
+		}
+		b.Children(func() {
+			ui.Icon(c, icons.Must("arrow-down")).Size(16, 16)
+			if unread > 0 {
+				ui.Text(c, fmt.Sprint(unread)).FontFeatures("tnum").FontWeight(600).TextColor(k.AccentText).SingleLine()
+			}
+		})
+	})
+	return b
+}