Data commit

Task/GUI-component-interaction/Go/gui-component-interaction.go

@@ -0,0 +1,99 @@
+package main
+
+import (
+    "github.com/gotk3/gotk3/gtk"
+    "log"
+    "math/rand"
+    "strconv"
+    "time"
+)
+
+func validateInput(window *gtk.Window, str string) (int64, bool) {
+    i, err := strconv.ParseInt(str, 10, 64)
+    if err != nil {
+        dialog := gtk.MessageDialogNew(
+            window,
+            gtk.DIALOG_MODAL,
+            gtk.MESSAGE_ERROR,
+            gtk.BUTTONS_OK,
+            "Invalid value",
+        )
+        dialog.Run()
+        dialog.Destroy()
+        return 0, false
+    }
+    return i, true
+}
+
+func check(err error, msg string) {
+    if err != nil {
+        log.Fatal(msg, err)
+    }
+}
+
+func main() {
+    rand.Seed(time.Now().UnixNano())
+    gtk.Init(nil)
+
+    window, err := gtk.WindowNew(gtk.WINDOW_TOPLEVEL)
+    check(err, "Unable to create window:")
+    window.SetTitle("Rosetta Code")
+    window.SetPosition(gtk.WIN_POS_CENTER)
+    window.Connect("destroy", func() {
+        gtk.MainQuit()
+    })
+
+    box, err := gtk.BoxNew(gtk.ORIENTATION_HORIZONTAL, 1)
+    check(err, "Unable to create box:")
+    box.SetBorderWidth(1)
+
+    label, err := gtk.LabelNew("Value:")
+    check(err, "Unable to create label:")
+
+    entry, err := gtk.EntryNew()
+    check(err, "Unable to create entry:")
+    entry.SetText("0") // initialize to zero
+    entry.Connect("activate", func() {
+        // read and validate the entered value
+        str, _ := entry.GetText()
+        validateInput(window, str)
+    })
+
+    // button to increment
+    ib, err := gtk.ButtonNewWithLabel("Increment")
+    check(err, "Unable to create increment button:")
+    ib.Connect("clicked", func() {
+        // read and validate the entered value
+        str, _ := entry.GetText()
+        if i, ok := validateInput(window, str); ok {
+            entry.SetText(strconv.FormatInt(i+1, 10))
+        }
+    })
+
+    // button to put in a random value if confirmed
+    rb, err := gtk.ButtonNewWithLabel("Random")
+    check(err, "Unable to create random button:")
+    rb.Connect("clicked", func() {
+        dialog := gtk.MessageDialogNew(
+            window,
+            gtk.DIALOG_MODAL,
+            gtk.MESSAGE_QUESTION,
+            gtk.BUTTONS_YES_NO,
+            "Set random value",
+        )
+        answer := dialog.Run()
+        dialog.Destroy()
+        if answer == gtk.RESPONSE_YES {
+            entry.SetText(strconv.Itoa(rand.Intn(10000)))
+        }
+    })
+
+    box.PackStart(label, false, false, 2)
+    box.PackStart(entry, false, false, 2)
+    box.PackStart(ib, false, false, 2)
+    box.PackStart(rb, false, false, 2)
+    window.Add(box)
+
+    window.ShowAll()
+    gtk.Main()
+}