Gtk::Button and Signals

Buttons are widgets that creates a signal when clicked on, plain and simple.

• Gtk::Button
• Add a button as you would any other widget.
• Hold any widget, the most common being the Gtk::Label.
• Be fancy: hold an image.
• Other button subclasses exist which extend the functionality
• Gtk::ToggleButton
• Gtk::CheckButton
• Gtk::RadioButton
• Signals
• Every widget sports some type of signal, usually of the form signal_action() where action defines the event action of the signal.
• The Gtk::Button class defines the following:
• Glib::SignalProxy0 signal_activate ()
• Glib::SignalProxy0 signal_clicked ()
• Glib::SignalProxy0 signal_enter ()
• Glib::SignalProxy0 signal_leave ()
• Glib::SignalProxy0 signal_pressed ()
• Glib::SignalProxy0 signal_released ()
• In most cases, signal_clicked is your friend.

Example: Button

main.cc:

#include <gtkmm/main.h>
#include "buttons.h"

int main(int argc, char *argv[])
{
  Gtk::Main kit(argc, argv);

  Buttons buttons;
  Gtk::Main::run(buttons); //Shows the window and returns when it is closed.

  return 0;
}

buttons.h:

#ifndef GTKMM_EXAMPLE_BUTTONS_H
#define GTKMM_EXAMPLE_BUTTONS_H

#include <gtkmm/window.h>
#include <gtkmm/button.h>

class Buttons : public Gtk::Window
{
public:
  Buttons();
  virtual ~Buttons();

protected:
  //Signal handlers:
  virtual void on_button_clicked();

  //Child widgets:
  Gtk::Button m_button;
};

#endif //GTKMM_EXAMPLE_BUTTONS_H

buttons.cc:

#include "buttons.h"
#include <iostream>

Buttons::Buttons()
{
  m_button.add_pixlabel("info.xpm", "cool button");

  set_title("Pixmap'd buttons!");
  set_border_width(10);

  m_button.signal_clicked().connect( sigc::mem_fun(*this, &Buttons::on_button_clicked) );

  add(m_button);

  show_all_children();
}

Buttons::~Buttons()
{
}

void Buttons::on_button_clicked()
{
  std::cout << "The Button was clicked." << std::endl;
}