added main learning file

main.go

@@ -0,0 +1,21 @@
+package main
+
+import (
+	"github.com/rivo/tview"
+)
+
+func main() {
+	app := tview.NewApplication().
+		EnableMouse(true)
+	modal := tview.NewModal().
+		SetText("Do you want to quit the application?").
+		AddButtons([]string{"Quit", "Cancel"}).
+		SetDoneFunc(func(buttonIndex int, buttonLabel string) {
+			if buttonLabel == "Quit" {
+				app.Stop()
+			}
+		})
+	if err := app.SetRoot(modal, false).SetFocus(modal).Run(); err != nil {
+		panic(err)
+	}
+}