package main

import (
	"github.com/gotk3/gotk3/gtk"
	"log"
)

func main() {
	// Initialize GTK without parsing any command line arguments.
	gtk.Init(nil)

	// Create a new toplevel window, set its title, and connect it to the
	// "destroy" signal to exit the GTK main loop when it is destroyed.
	win, err := gtk.WindowNew(gtk.WINDOW_TOPLEVEL)
	if err != nil {
		log.Fatal("Unable to create window:", err)
	}
	win.SetTitle("Simple Example")
	win.Connect("destroy", func() {
		gtk.MainQuit()
	})

	// Create a new label widget to show in the window.
	l, err := gtk.LabelNew("Hello, gotk3!")
	if err != nil {
		log.Fatal("Unable to create label:", err)
	}

	// Add the label to the window.
	win.Add(l)

	// Set the default window size.
	win.SetDefaultSize(800, 600)

	// Recursively show all widgets contained in this window.
	win.ShowAll()

	// Begin executing the GTK main loop.  This blocks until
	// gtk.MainQuit() is run. 
	gtk.Main()
}

package main

import (
	"log"
	"os"

	"github.com/gotk3/gotk3/glib"
	"github.com/gotk3/gotk3/gtk"
)

// Simple Gtk3 Application written in go.
// This application creates a window on the application callback activate.
// More GtkApplication info can be found here -> https://wiki.gnome.org/HowDoI/GtkApplication

func main() {
	// Create Gtk Application, change appID to your application domain name reversed.
	const appID = "org.gtk.example"
	application, err := gtk.ApplicationNew(appID, glib.APPLICATION_FLAGS_NONE)
	// Check to make sure no errors when creating Gtk Application
	if err != nil {
		log.Fatal("Could not create application.", err)
	}
	// Application signals available
	// startup -> sets up the application when it first starts
	// activate -> shows the default first window of the application (like a new document). This corresponds to the application being launched by the desktop environment.
	// open -> opens files and shows them in a new window. This corresponds to someone trying to open a document (or documents) using the application from the file browser, or similar.
	// shutdown ->  performs shutdown tasks
	// Setup Gtk Application callback signals
	application.Connect("activate", func() { onActivate(application) })
	// Run Gtk application
	os.Exit(application.Run(os.Args))
}

// Callback signal from Gtk Application
func onActivate(application *gtk.Application) {
	// Create ApplicationWindow
	appWindow, err := gtk.ApplicationWindowNew(application)
	if err != nil {
		log.Fatal("Could not create application window.", err)
	}
	// Set ApplicationWindow Properties
	appWindow.SetTitle("Basic Application.")
	appWindow.SetDefaultSize(400, 400)
	appWindow.Show()
}

package main

import (
	"log"
	"os"

	"github.com/gotk3/gotk3/glib"
	"github.com/gotk3/gotk3/gtk"
)

// Simple Gtk3 Application written in go.
// This application creates a window on the application callback activate.
// More GtkApplication info can be found here -> https://wiki.gnome.org/HowDoI/GtkApplication

func main() {
	// Create Gtk Application, change appID to your application domain name reversed.
	const appID = "org.gtk.example"
	application, err := gtk.ApplicationNew(appID, glib.APPLICATION_FLAGS_NONE)
	// Check to make sure no errors when creating Gtk Application
	if err != nil {
		log.Fatal("Could not create application.", err)
	}

	// Application signals available
	// startup -> sets up the application when it first starts
	// activate -> shows the default first window of the application (like a new document). This corresponds to the application being launched by the desktop environment.
	// open -> opens files and shows them in a new window. This corresponds to someone trying to open a document (or documents) using the application from the file browser, or similar.
	// shutdown ->  performs shutdown tasks
	// Setup activate signal with a closure function.
	application.Connect("activate", func() {
		// Create ApplicationWindow
		appWindow, err := gtk.ApplicationWindowNew(application)
		if err != nil {
			log.Fatal("Could not create application window.", err)
		}
		// Set ApplicationWindow Properties
		appWindow.SetTitle("Basic Application.")
		appWindow.SetDefaultSize(400, 400)
		appWindow.Show()
	})
	// Run Gtk application
	application.Run(os.Args)
}