Entry

8.2.1. Uso simple

Los widgets de «entry» le permiten al usuario introducir texto. Puede cambiar el contenido con el método set_text(), y leer el contenido actual con el método get_text().

Ocasionalmente querrá definir un widget Entry como sólo lectura. Esto se puede hacer pasándole false al método set_editable().

Para introducir contraseñas, frases de paso, y otra información que no quiera que aparezca en la pantalla, llamar a set_visibility con false hará que el texto permanezca oculto.

You might want to be notified whenever the user types in a text entry widget. Gtk::Entry provides two signals, activate and changed, for 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. Moving the keyboard focus to another widget may also signal that the user has finished entering text. The focus_out_event signal that Gtk::Entry inherits from Gtk::Widget can notify you when that happens. The ComboBox with an Entry section contains example programs that use these signals.

If you pass true to the set_activates_default() method, pressing Enter in the Gtk::Entry will activate the default widget for the window containing the Gtk::Entry. This is especially useful in dialog boxes. The default widget is usually one of the dialog buttons, which e.g. will close the dialog box. To set a widget as the default widget, use Gtk::Widget::set_can_default() and Gtk::Widget::grab_default().

Reference

8.2.1.1. Ejemplo simple de «Entry»

Este ejemplo usa Gtk::Entry. También tiene dos CheckButton, con los que puede conmutar las opciones «editable» y «visible».

Figura 8-2Entry

Source Code

File: examplewindow.h (For use with gtkmm 4)

#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include <gtkmm.h>

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

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

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

#endif //GTKMM_EXAMPLEWINDOW_H

File: main.cc (For use with gtkmm 4)

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

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create("org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app->run(window, argc, argv);
}

File: examplewindow.cc (For use with gtkmm 4)

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

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::Orientation::VERTICAL),
  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_Entry.set_expand(true);
  m_VBox.add(m_Entry);

  m_VBox.add(m_HBox);

  m_HBox.add(m_CheckButton_Editable);
  m_CheckButton_Editable.set_expand(true);
  m_CheckButton_Editable.signal_toggled().connect( sigc::mem_fun(*this,
              &ExampleWindow::on_checkbox_editable_toggled) );
  m_CheckButton_Editable.set_active(true);

  m_HBox.add(m_CheckButton_Visible);
  m_CheckButton_Visible.set_expand(true);
  m_CheckButton_Visible.signal_toggled().connect( sigc::mem_fun(*this,
              &ExampleWindow::on_checkbox_visibility_toggled) );
  m_CheckButton_Visible.set_active(true);

  m_Button_Close.signal_clicked().connect( sigc::mem_fun(*this,
              &ExampleWindow::on_button_close) );
  m_VBox.add(m_Button_Close);
  m_Button_Close.set_expand();
  set_default_widget(m_Button_Close);
}

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();
}

8.2.2. Completado de «Entry»

An Entry widget can offer a drop-down list of pre-existing choices based on the first few characters typed by the user. For instance, a search dialog could suggest text from previous searches.

To enable this functionality, you must create an EntryCompletion object, and provide it to the Entry widget via the set_completion() method.

El EntryCompletion puede usar un TreeModel que contenga las entradas posibles, especificadas por set_model(). Luego llame a set_text_column() para especificar cuál de las columnas de su modelo debe usarse para las posibles entradas de texto.

Alternativamente, si una lista completa de entradas posibles fuera muy larga o demasiado incómoda para generar, puede especificar en su lugar un espacio para una retrollamada con set_match_func(). Esto también es útil si no desea usar el principio de la cadena.

Reference

8.2.2.1. Ejemplo de completado de «Entry»

Este ejemplo crea un Gtk::EntryCompletion y lo asocia a un widget Gtk::Entry. Se usan un Gtk::TreeModel de entradas posibles para el completado y algunas acciones adicionales.

Figura 8-3Completado de «Entry»

Source Code

File: examplewindow.h (For use with gtkmm 4)

#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include <gtkmm.h>

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

protected:
  //Signal handlers:
  void on_button_close();

  void on_completion_action_activated(int index);

  //See the comment in the implementation:
  //bool on_completion_match(const Glib::ustring& key, const Gtk::TreeModel::const_iterator& iter);


  //Tree model columns, for the EntryCompletion's filter model:
  class ModelColumns : public Gtk::TreeModel::ColumnRecord
  {
  public:

    ModelColumns()
    { add(m_col_id); add(m_col_name); }

    Gtk::TreeModelColumn<unsigned int> m_col_id;
    Gtk::TreeModelColumn<Glib::ustring> m_col_name;
  };

  ModelColumns m_Columns;

  typedef std::map<int, Glib::ustring> type_actions_map;
  type_actions_map m_CompletionActions;

  //Child widgets:
  Gtk::Box m_HBox;
  Gtk::Box m_VBox;
  Gtk::Entry m_Entry;
  Gtk::Label m_Label;
  Gtk::Button m_Button_Close;
};

#endif //GTKMM_EXAMPLEWINDOW_H

File: main.cc (For use with gtkmm 4)

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

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create("org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app->run(window, argc, argv);
}

File: examplewindow.cc (For use with gtkmm 4)

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

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::Orientation::VERTICAL),
  m_Label("Press a or b to see a list of possible completions and actions."),
  m_Button_Close("Close")
{
  //set_size_request(200, 100);
  set_title("Gtk::EntryCompletion");

  add(m_VBox);
  m_VBox.add(m_Entry);

  m_VBox.add(m_Label);
  m_Label.set_expand(true);

  m_Button_Close.signal_clicked().connect( sigc::mem_fun(*this,
              &ExampleWindow::on_button_close) );
  m_VBox.add(m_Button_Close);
  set_default_widget(m_Button_Close);

  //Add an EntryCompletion:
  auto completion =
      Gtk::EntryCompletion::create();
  m_Entry.set_completion(completion);

  //Create and fill the completion's filter model
  auto refCompletionModel =
      Gtk::ListStore::create(m_Columns);
  completion->set_model(refCompletionModel);

  // For more complex comparisons, use a filter match callback, like this.
  // See the comment below for more details:
  //completion->set_match_func( sigc::mem_fun(*this,
              //&ExampleWindow::on_completion_match) );

  //Fill the TreeView's model
  auto row = *(refCompletionModel->append());
  row[m_Columns.m_col_id] = 1;
  row[m_Columns.m_col_name] = "Alan Zebedee";

  row = *(refCompletionModel->append());
  row[m_Columns.m_col_id] = 2;
  row[m_Columns.m_col_name] = "Adrian Boo";

  row = *(refCompletionModel->append());
  row[m_Columns.m_col_id] = 3;
  row[m_Columns.m_col_name] = "Bob McRoberts";

  row = *(refCompletionModel->append());
  row[m_Columns.m_col_id] = 4;
  row[m_Columns.m_col_name] = "Bob McBob";

  //Tell the completion what model column to use to
  //- look for a match (when we use the default matching, instead of
  //  set_match_func().
  //- display text in the entry when a match is found.
  completion->set_text_column(m_Columns.m_col_name);

  //Add actions to the completion:
  //These are just extra items shown at the bottom of the list of possible
  //completions.

  //Remember them for later.
  m_CompletionActions[0] = "Use Wizard";
  m_CompletionActions[1] = "Browse for Filename";

  for(const auto& the_pair : m_CompletionActions)
  {
    auto position = the_pair.first;
    auto title = the_pair.second;
    completion->insert_action_text(title, position);
  }

  completion->signal_action_activated().connect( sigc::mem_fun(*this,
              &ExampleWindow::on_completion_action_activated) );
}

ExampleWindow::~ExampleWindow()
{
}

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

/* You can do more complex matching with a handler like this.
 * For instance, you could check for substrings inside the string instead of the start,
 * or you could look for the key in extra model columns as well as the model column that will be displayed.
 * The code here is not actually more complex - it's a reimplementation of the default behaviour.
 *
bool ExampleWindow::on_completion_match(const Glib::ustring& key, const
        Gtk::TreeModel::const_iterator& iter)
{
  if(iter)
  {
    const auto row = *iter;

    const auto key_length = key.size();
    auto filter_string = row[m_Columns.m_col_name];

    auto filter_string_start = filter_string.substr(0, key_length);
    //The key is lower-case, even if the user input is not.
    filter_string_start = filter_string_start.lowercase();

    if(key == filter_string_start)
      return true; //A match was found.
  }

  return false; //No match.
}
*/

void ExampleWindow::on_completion_action_activated(int index)
{
  auto iter = m_CompletionActions.find(index);
  if(iter != m_CompletionActions.end()) //If it's in the map
  {
    auto title = iter->second;
    std::cout << "Action selected: " << title << std::endl;
  }
}

8.2.3. Iconos de «Entry»

An Entry widget can show an icon at the start or end of the text area. The icon can be specifed by methods such as set_icon_from_pixbuf() or set_icon_from_icon_name(). An application can respond to the user pressing the icon by handling the signal_icon_press signal.

8.2.3.1. Ejemplo de icono de «Entry»

Este ejemplo muestra un widget Gtk::Entry con un icono de búsqueda del almacén, e imprime texto en la terminal cuando se pulsa el icono.

Figura 8-4«Entry» con icono

Source Code

File: examplewindow.h (For use with gtkmm 4)

#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include <gtkmm.h>

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

protected:
  //Signal handlers:
  void on_icon_pressed(Gtk::Entry::IconPosition icon_pos);
  void on_button_close();

  //Child widgets:
  Gtk::Box m_VBox;
  Gtk::Entry m_Entry;
  Gtk::Button m_Button_Close;
};

#endif //GTKMM_EXAMPLEWINDOW_H

File: main.cc (For use with gtkmm 4)

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

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create("org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app->run(window, argc, argv);
}

File: examplewindow.cc (For use with gtkmm 4)

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

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::Orientation::VERTICAL),
  m_Button_Close("Close")
{
  set_title("Gtk::Entry");

  add(m_VBox);

  m_Entry.set_max_length(50);
  m_Entry.set_text("Hello world");
  m_VBox.add(m_Entry);

  m_Entry.set_icon_from_icon_name("edit-find");
  m_Entry.signal_icon_press().connect( sigc::mem_fun(*this, &ExampleWindow::on_icon_pressed) );


  m_Button_Close.signal_clicked().connect( sigc::mem_fun(*this,
              &ExampleWindow::on_button_close) );
  m_VBox.add(m_Button_Close);
  set_default_widget(m_Button_Close);
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_icon_pressed(Gtk::Entry::IconPosition /* icon_pos */)
{
  std::cout << "Icon pressed." << std::endl;
}

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

8.2.4. «Entry» de progreso

Un widget Entry puede mostrar una barra de progreso dentro del área del texto, bajo el texto introducido. La barra de progreso se mostrará si se llama a los métodos set_progress_fraction() o set_progress_pulse_step().

8.2.4.1. Ejemplo de «Entry» de progreso

Este ejemplo muestra un widget Gtk::Entry con una barra de progreso.

Figura 8-5«Entry» con barra de progreso

Source Code

File: examplewindow.h (For use with gtkmm 4)

#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include <gtkmm.h>

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

protected:
  //Signal handlers:
  bool on_timeout();
  void on_button_close();

  //Child widgets:
  Gtk::Box m_VBox;
  Gtk::Entry m_Entry;
  Gtk::Button m_Button_Close;
};

#endif //GTKMM_EXAMPLEWINDOW_H

File: main.cc (For use with gtkmm 4)

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

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create("org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app->run(window, argc, argv);
}

File: examplewindow.cc (For use with gtkmm 4)

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

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::Orientation::VERTICAL),
  m_Button_Close("Close")
{
  set_title("Gtk::Entry");

  add(m_VBox);

  m_Entry.set_max_length(50);
  m_Entry.set_text("Hello world");
  m_VBox.add(m_Entry);

  //Change the progress fraction every 0.1 second:
  Glib::signal_timeout().connect(
    sigc::mem_fun(*this, &ExampleWindow::on_timeout),
    100
  );

  m_Button_Close.signal_clicked().connect( sigc::mem_fun(*this,
              &ExampleWindow::on_button_close) );
  m_VBox.add(m_Button_Close);
  set_default_widget(m_Button_Close);
}

ExampleWindow::~ExampleWindow()
{
}

bool ExampleWindow::on_timeout()
{
  static double fraction = 0;
  m_Entry.set_progress_fraction(fraction);

  fraction += 0.01;
  if(fraction > 1)
    fraction = 0;

  return true;
}

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