try fyne

cmd/fyne/main.go

@@ -0,0 +1,25 @@
+package main
+
+import (
+	"time"
+
+	"fyne.io/fyne/v2/app"
+	"fyne.io/fyne/v2/widget"
+)
+
+func main() {
+	a := app.New()
+	w := a.NewWindow("Hello World")
+	defer w.ShowAndRun()
+
+	l := widget.NewLabel("")
+	w.SetContent(l)
+
+	go func() {
+		for range time.NewTicker(time.Second).C {
+			{
+				l.SetText(time.Now().Format("2006-01-02T15:04:05"))
+			}
+		}
+	}()
+}