Entry

Entry
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Entry widgets allow the user to enter text (surprisingly enough).

You can change the contents with the set_text() method, and read the current contents with the get_text() method.

Occasionally you might want to make an Entry widget read-only. This can be done by passing false to the set_editable() method.

For the input of passwords, passphrases and other information you don't want echoed on the screen, calling set_visibility() with false will cause the text to be hidden.

You might want to be notified whenever the user types in a text entry widget. Gtk::Entry provides two signals, activate and changed, for just this purpose. activate is emitted when the user presses the enter key in a text-entry widget; changed is emitted when the text in the widget changes. You can use these, for instance, to validate or filter the text the user types.

Reference

Example

Here is an example using Gtk::Entry. As well as a Gtk::Entry widget, it has two CheckButtons, with which you can toggle the editable and visible flags.

Figure 6.2. Entry

Source Code

File: examplewindow.h

#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include <gtkmm.h>

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

protected:
  //Signal handlers:
  virtual void on_checkbox_editable_toggled();
  virtual void on_checkbox_visibility_toggled();
  virtual void on_button_close();

  //Child widgets:
  Gtk::HBox m_HBox;
  Gtk::VBox m_VBox;
  Gtk::Entry m_Entry;
  Gtk::Button m_Button_Close;
  Gtk::CheckButton m_CheckButton_Editable, m_CheckButton_Visible;
};

#endif //GTKMM_EXAMPLEWINDOW_H

File: examplewindow.cc

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

ExampleWindow::ExampleWindow()
: m_Button_Close("Close"),
  m_CheckButton_Editable("Editable"),
  m_CheckButton_Visible("Visible")
{
  set_size_request(200, 100);
  set_title("Gtk::Entry");

  add(m_VBox);

  m_Entry.set_max_length(50);
  m_Entry.set_text("hello");
  m_Entry.set_text(m_Entry.get_text() + " world");
  m_Entry.select_region(0, m_Entry.get_text_length());
  m_VBox.pack_start(m_Entry);

  // Note that add() can also be used instead of pack_xxx()
  m_VBox.add(m_HBox);

  m_HBox.pack_start(m_CheckButton_Editable);
  m_CheckButton_Editable.signal_toggled().connect( SigC::slot(*this, &ExampleWindow::on_checkbox_editable_toggled) );
  m_CheckButton_Editable.set_active(true);

  m_HBox.pack_start(m_CheckButton_Visible);
  m_CheckButton_Visible.signal_toggled().connect( SigC::slot(*this, &ExampleWindow::on_checkbox_visibility_toggled) );
  m_CheckButton_Visible.set_active(true);

  m_Button_Close.signal_clicked().connect( SigC::slot(*this, &ExampleWindow::on_button_close) );
  m_VBox.pack_start(m_Button_Close);
  m_Button_Close.set_flags(Gtk::CAN_DEFAULT);
  m_Button_Close.grab_default();

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_checkbox_editable_toggled()
{
  m_Entry.set_editable(m_CheckButton_Editable.get_active());
}

void ExampleWindow::on_checkbox_visibility_toggled()
{
  m_Entry.set_visibility(m_CheckButton_Visible.get_active());
}

void ExampleWindow::on_button_close()
{
  hide();
}

File: main.cc

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

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

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

  return 0;
}