Module: Gtk::Editable

Defined in:
(unknown)

Overview

GtkEditable is an interface for text editing widgets.

Typical examples of editable widgets are [classGtk.Entry] and [classGtk.SpinButton]. It contains functions for generically manipulating an editable widget, a large number of action signals used for key bindings, and several signals that an application can connect to modify the behavior of a widget.

As an example of the latter usage, by connecting the following handler to [signalGtk.Editable::insert-text], an application can convert all entry into a widget into uppercase.

Forcing entry to uppercase.

#include <ctype.h>

void
insert_text_handler (GtkEditable *editable,
                     const char  *text,
                     int          length,
                     int         *position,
                     gpointer     data)
{
  char *result = g_utf8_strup (text, length);

  g_signal_handlers_block_by_func (editable,
                               (gpointer) insert_text_handler, data);
  gtk_editable_insert_text (editable, result, length, position);
  g_signal_handlers_unblock_by_func (editable,
                                     (gpointer) insert_text_handler, data);

  g_signal_stop_emission_by_name (editable, "insert_text");

  g_free (result);
}

Implementing GtkEditable

The most likely scenario for implementing GtkEditable on your own widget is that you will embed a GtkText inside a complex widget, and want to delegate the editable functionality to that text widget. GtkEditable provides some utility functions to make this easy.

In your class_init function, call [funcGtk.Editable.install_properties], passing the first available property ID:

static void
my_class_init (MyClass *class)
{
  ...
  g_object_class_install_properties (object_class, NUM_PROPERTIES, props);
  gtk_editable_install_properties (object_clas, NUM_PROPERTIES);
  ...
}

In your interface_init function for the GtkEditable interface, provide an implementation for the get_delegate vfunc that returns your text widget:

GtkEditable *
get_editable_delegate (GtkEditable *editable)
{
  return GTK_EDITABLE (MY_WIDGET (editable)->text_widget);
}

static void
my_editable_init (GtkEditableInterface *iface)
{
  iface->get_delegate = get_editable_delegate;
}

You don't need to provide any other vfuncs. The default implementations work by forwarding to the delegate that the GtkEditableInterface.get_delegate() vfunc returns.

In your instance_init function, create your text widget, and then call [methodGtk.Editable.init_delegate]:

static void
my_widget_init (MyWidget *self)
{
  ...
  self->text_widget = gtk_text_new ();
  gtk_editable_init_delegate (GTK_EDITABLE (self));
  ...
}

In your dispose function, call [methodGtk.Editable.finish_delegate] before destroying your text widget:

static void
my_widget_dispose (GObject *object)
{
  ...
  gtk_editable_finish_delegate (GTK_EDITABLE (self));
  g_clear_pointer (&self->text_widget, gtk_widget_unparent);
  ...
}

Finally, use [funcGtk.Editable.delegate_set_property] in your set_property function (and similar for get_property), to set the editable properties:

  ...
  if (gtk_editable_delegate_set_property (object, prop_id, value, pspec))
    return;

  switch (prop_id)
  ...

It is important to note that if you create a GtkEditable that uses a delegate, the low level [signalGtk.Editable::insert-text] and [signalGtk.Editable::delete-text] signals will be propagated from the "wrapper" editable to the delegate, but they will not be propagated from the delegate to the "wrapper" editable, as they would cause an infinite recursion. If you wish to connect to the [signalGtk.Editable::insert-text] and [signalGtk.Editable::delete-text] signals, you will need to connect to them on the delegate obtained via [methodGtk.Editable.get_delegate].

Instance Method Summary collapse

Instance Method Details

#alignment ⇒ Gtk::gfloat

Gets the alignment of the editable.

Returns:

  • (Gtk::gfloat) —

    the alignment

#alignment=(xalign) ⇒ nil

Sets the alignment for the contents of the editable.

This controls the horizontal positioning of the contents when the displayed text is shorter than the width of the editable.

Parameters:

  • xalign (Gtk::gfloat) —

    The horizontal alignment, from 0 (left) to 1 (right). Reversed for RTL layouts

Returns:

  • (nil)

#changed ⇒ nil

Returns:

  • (nil)

#delegate ⇒ Gtk::Editable

Gets the GtkEditable that editable is delegating its implementation to.

Typically, the delegate is a [classGtk.Text] widget.

Returns:

#delegate_get_accessible_platform_state(state) ⇒ Boolean

Retrieves the accessible platform state from the editable delegate.

This is an helper function to retrieve the accessible state for GtkEditable interface implementations using a delegate pattern.

You should call this function in your editable widget implementation of the [vfuncGtk.Accessible.get_platform_state] virtual function, for instance:

static void
accessible_interface_init (GtkAccessibleInterface *iface)
{
  iface->get_platform_state = your_editable_get_accessible_platform_state;
}

static gboolean
your_editable_get_accessible_platform_state (GtkAccessible *accessible,
                                             GtkAccessiblePlatformState state)
{
  return gtk_editable_delegate_get_accessible_platform_state (GTK_EDITABLE (accessible), state);
}

Parameters:

Returns:

  • (Boolean)

#delete_selection ⇒ nil

Deletes the currently selected text of the editable.

This call doesn’t do anything if there is no selected text.

Returns:

  • (nil)

#delete_text(start_pos, end_pos) ⇒ nil

Deletes a sequence of characters.

The characters that are deleted are those characters at positions from start_pos up to, but not including end_pos. If end_pos is negative, then the characters deleted are those from start_pos to the end of the text.

Note that the positions are specified in characters, not bytes.

Parameters:

  • start_pos (Integer) —

    start position

  • end_pos (Integer) —

    end position

Returns:

  • (nil)

#do_delete_text(start_pos, end_pos) ⇒ nil

Deletes a sequence of characters.

The characters that are deleted are those characters at positions from start_pos up to, but not including end_pos. If end_pos is negative, then the characters deleted are those from start_pos to the end of the text.

Note that the positions are specified in characters, not bytes.

Parameters:

  • start_pos (Integer) —

    start position

  • end_pos (Integer) —

    end position

Returns:

  • (nil)

#do_insert_text(text, length, position) ⇒ nil

Inserts length bytes of text into the contents of the widget, at position position.

Note that the position is in characters, not in bytes. The function updates position to point after the newly inserted text.

Parameters:

  • text (String) —

    the text to insert

  • length (Integer) —

    the length of the text in bytes, or -1

  • position (Integer) —

    location of the position text will be inserted at

Returns:

  • (nil)

#editable ⇒ Boolean

Retrieves whether editable is editable.

Returns:

  • (Boolean) —

    true if editable is editable.

#editable=(is_editable) ⇒ nil

Determines if the user can edit the text in the editable widget.

Parameters:

  • is_editable (Boolean) —

    true if the user is allowed to edit the text in the widget

Returns:

  • (nil)

#enable_undo ⇒ Boolean

Gets if undo/redo actions are enabled for editable

Returns:

  • (Boolean) —

    true if undo is enabled

#enable_undo=(enable_undo) ⇒ nil

If enabled, changes to editable will be saved for undo/redo actions.

This results in an additional copy of text changes and are not stored in secure memory. As such, undo is forcefully disabled when [propertyGtk.Text:visibility] is set to false.

Parameters:

  • enable_undo (Boolean) —

    if undo/redo should be enabled

Returns:

  • (nil)

#finish_delegate ⇒ nil

Undoes the setup done by [methodGtk.Editable.init_delegate].

This is a helper function that should be called from dispose, before removing the delegate object.

Returns:

  • (nil)

#get_chars(start_pos, end_pos) ⇒ String

Retrieves a sequence of characters.

The characters that are retrieved are those characters at positions from start_pos up to, but not including end_pos. If end_pos is negative, then the characters retrieved are those characters from start_pos to the end of the text.

Note that positions are specified in characters, not bytes.

Parameters:

  • start_pos (Integer) —

    start of text

  • end_pos (Integer) —

    end of text

Returns:

  • (String) —

    a pointer to the contents of the widget as a string. This string is allocated by the GtkEditable implementation and should be freed by the caller.

#get_selection_bounds(start_pos, end_pos) ⇒ Boolean

Retrieves the selection bound of the editable.

start_pos will be filled with the start of the selection and end_pos with end. If no text was selected both will be identical and false will be returned.

Note that positions are specified in characters, not bytes.

Parameters:

  • start_pos (Integer) —

    location to store the starting position

  • end_pos (Integer) —

    location to store the end position

Returns:

  • (Boolean) —

    true if there is a non-empty selection, false otherwise

#init_delegate ⇒ nil

Sets up a delegate for GtkEditable.

This is assuming that the get_delegate vfunc in the GtkEditable interface has been set up for the editable's type.

This is a helper function that should be called in instance init, after creating the delegate object.

Returns:

  • (nil)

#insert_text(text, length, position) ⇒ nil

Inserts length bytes of text into the contents of the widget, at position position.

Note that the position is in characters, not in bytes. The function updates position to point after the newly inserted text.

Parameters:

  • text (String) —

    the text to insert

  • length (Integer) —

    the length of the text in bytes, or -1

  • position (Integer) —

    location of the position text will be inserted at

Returns:

  • (nil)

#max_width_chars ⇒ Integer

Retrieves the desired maximum width of editable, in characters.

Returns:

  • (Integer) —

    the maximum width of the entry, in characters

#max_width_chars=(n_chars) ⇒ nil

Sets the desired maximum width in characters of editable.

Parameters:

  • n_chars (Integer) —

    the new desired maximum width, in characters

Returns:

  • (nil)

#position ⇒ Integer

Retrieves the current position of the cursor relative to the start of the content of the editable.

Note that this position is in characters, not in bytes.

Returns:

  • (Integer) —

    the cursor position

#position=(position) ⇒ nil

Sets the cursor position in the editable to the given value.

The cursor is displayed before the character with the given (base 0) index in the contents of the editable. The value must be less than or equal to the number of characters in the editable. A value of -1 indicates that the position should be set after the last character of the editable. Note that position is in characters, not in bytes.

Parameters:

  • position (Integer) —

    the position of the cursor

Returns:

  • (nil)

#select_region(start_pos, end_pos) ⇒ nil

Selects a region of text.

The characters that are selected are those characters at positions from start_pos up to, but not including end_pos. If end_pos is negative, then the characters selected are those characters from start_pos to the end of the text.

Note that positions are specified in characters, not bytes.

Parameters:

  • start_pos (Integer) —

    start of region

  • end_pos (Integer) —

    end of region

Returns:

  • (nil)

#set_selection_bounds(start_pos, end_pos) ⇒ nil

Selects a region of text.

The characters that are selected are those characters at positions from start_pos up to, but not including end_pos. If end_pos is negative, then the characters selected are those characters from start_pos to the end of the text.

Note that positions are specified in characters, not bytes.

Parameters:

  • start_pos (Integer) —

    start of region

  • end_pos (Integer) —

    end of region

Returns:

  • (nil)

#text ⇒ String

Retrieves the contents of editable.

The returned string is owned by GTK and must not be modified or freed.

Returns:

  • (String) —

    a pointer to the contents of the editable

#text=(text) ⇒ nil

Sets the text in the editable to the given value.

This is replacing the current contents.

Parameters:

  • text (String) —

    the text to set

Returns:

  • (nil)

#width_chars ⇒ Integer

Gets the number of characters of space reserved for the contents of the editable.

Returns:

  • (Integer) —

    number of chars to request space for, or negative if unset

#width_chars=(n_chars) ⇒ nil

Changes the size request of the editable to be about the right size for n_chars characters.

Note that it changes the size request, the size can still be affected by how you pack the widget into containers. If n_chars is -1, the size reverts to the default size.

Parameters:

  • n_chars (Integer) —

    width in chars

Returns:

  • (nil)