Forcing entry to uppercase.

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#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 gtk_editable_install_properties(), passing the first available property ID:

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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:

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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 gtk_editable_init_delegate():

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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 gtk_editable_finish_delegate() before destroying your text widget:

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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 gtk_editable_delegate_set_property() in your set_property function (and similar for get_property), to set the editable properties:

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...
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 “insert-text” and “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 “insert-text” and “delete-text” signals, you will need to connect to them on the delegate obtained via gtk_editable_get_delegate().

gtk_editable_get_text ()

const char *
gtk_editable_get_text (GtkEditable *editable);

Retrieves the contents of editable . The returned string is owned by GTK and must not be modified or freed.

gtk_editable_set_text ()

void
gtk_editable_set_text (GtkEditable *editable,
                       const char *text);

Sets the text in the editable to the given value, replacing the current contents.

gtk_editable_get_chars ()

char *
gtk_editable_get_chars (GtkEditable *editable,
                        int start_pos,
                        int end_pos);

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.

gtk_editable_insert_text ()

void
gtk_editable_insert_text (GtkEditable *editable,
                          const char *text,
                          int length,
                          int *position);

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.

[virtual do_insert_text]

gtk_editable_delete_text ()

void
gtk_editable_delete_text (GtkEditable *editable,
                          int start_pos,
                          int end_pos);

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.

[virtual do_delete_text]

gtk_editable_get_selection_bounds ()

gboolean
gtk_editable_get_selection_bounds (GtkEditable *editable,
                                   int *start_pos,
                                   int *end_pos);

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.

gtk_editable_select_region ()

void
gtk_editable_select_region (GtkEditable *editable,
                            int start_pos,
                            int end_pos);

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.

[virtual set_selection_bounds]

gtk_editable_delete_selection ()

void
gtk_editable_delete_selection (GtkEditable *editable);

Deletes the currently selected text of the editable. This call doesn’t do anything if there is no selected text.

gtk_editable_set_position ()

void
gtk_editable_set_position (GtkEditable *editable,
                           int position);

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.

gtk_editable_get_position ()

int
gtk_editable_get_position (GtkEditable *editable);

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.

gtk_editable_set_editable ()

void
gtk_editable_set_editable (GtkEditable *editable,
                           gboolean is_editable);

Determines if the user can edit the text in the editable widget or not.

gtk_editable_get_editable ()

gboolean
gtk_editable_get_editable (GtkEditable *editable);

Retrieves whether editable is editable. See gtk_editable_set_editable().

gtk_editable_set_alignment ()

void
gtk_editable_set_alignment (GtkEditable *editable,
                            float xalign);

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.

gtk_editable_get_alignment ()

float
gtk_editable_get_alignment (GtkEditable *editable);

Gets the value set by gtk_editable_set_alignment().

gtk_editable_get_width_chars ()

int
gtk_editable_get_width_chars (GtkEditable *editable);

Gets the value set by gtk_editable_set_width_chars().

gtk_editable_set_width_chars ()

void
gtk_editable_set_width_chars (GtkEditable *editable,
                              int n_chars);

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.

gtk_editable_get_max_width_chars ()

int
gtk_editable_get_max_width_chars (GtkEditable *editable);

Retrieves the desired maximum width of editable , in characters. See gtk_editable_set_max_width_chars().

gtk_editable_set_max_width_chars ()

void
gtk_editable_set_max_width_chars (GtkEditable *editable,
                                  int n_chars);

Sets the desired maximum width in characters of editable .

gtk_editable_get_enable_undo ()

gboolean
gtk_editable_get_enable_undo (GtkEditable *editable);

Gets if undo/redo actions are enabled for editable

gtk_editable_set_enable_undo ()

void
gtk_editable_set_enable_undo (GtkEditable *editable,
                              gboolean enable_undo);

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 “visibility” is set to FALSE.

gtk_editable_install_properties ()

guint
gtk_editable_install_properties (GObjectClass *object_class,
                                 guint first_prop);

Installs the GtkEditable properties for class .

This is a helper function that should be called in class_init, after installing your own properties.

To handle the properties in your set_property and get_property functions, you can either use gtk_editable_delegate_set_property() and gtk_editable_delegate_get_property() (if you are using a delegate), or remember the first_prop offset and add it to the values in the GtkEditableProperties enumeration to get the property IDs for these properties.

gtk_editable_get_delegate ()

GtkEditable *
gtk_editable_get_delegate (GtkEditable *editable);

Gets the GtkEditable that editable is delegating its implementation to. Typically, the delegate is a GtkText widget.

gtk_editable_init_delegate ()

void
gtk_editable_init_delegate (GtkEditable *editable);

Sets up a delegate for GtkEditable, 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.

gtk_editable_finish_delegate ()

void
gtk_editable_finish_delegate (GtkEditable *editable);

Undoes the setup done by gtk_editable_init_delegate().

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

gtk_editable_delegate_set_property ()

gboolean
gtk_editable_delegate_set_property (GObject *object,
                                    guint prop_id,
                                    const GValue *value,
                                    GParamSpec *pspec);

Sets a property on the GtkEditable delegate for object .

This is a helper function that should be called in set_property, before handling your own properties.

gtk_editable_delegate_get_property ()

gboolean
gtk_editable_delegate_get_property (GObject *object,
                                    guint prop_id,
                                    GValue *value,
                                    GParamSpec *pspec);

Gets a property of the GtkEditable delegate for object .

This is helper function that should be called in get_property, before handling your own properties.

GtkEditable

typedef struct _GtkEditable GtkEditable;

struct GtkEditableInterface

struct GtkEditableInterface {
  GTypeInterface                   base_iface;

  /* signals */
  void (* insert_text)              (GtkEditable    *editable,
                                     const char     *text,
                                     int             length,
                                     int            *position);
  void (* delete_text)              (GtkEditable    *editable,
                                     int             start_pos,
                                     int             end_pos);
  void (* changed)                  (GtkEditable    *editable);

  /* vtable */
  const char * (* get_text)         (GtkEditable    *editable);
  void     (* do_insert_text)       (GtkEditable    *editable,
                                     const char     *text,
                                     int             length,
                                     int            *position);
  void     (* do_delete_text)       (GtkEditable    *editable,
                                     int             start_pos,
                                     int             end_pos);

  gboolean (* get_selection_bounds) (GtkEditable    *editable,
                                     int            *start_pos,
                                     int            *end_pos);
  void     (* set_selection_bounds) (GtkEditable    *editable,
                                     int             start_pos,
                                     int             end_pos);
  GtkEditable * (* get_delegate)    (GtkEditable    *editable);
};

enum GtkEditableProperties

The “cursor-position” property

  “cursor-position”          int

The current position of the insertion cursor in chars.

Owner: GtkEditable

Flags: Read

Allowed values: [0,65535]

Default value: 0

The “editable” property

  “editable”                 gboolean

Whether the entry contents can be edited.

Owner: GtkEditable

Flags: Read / Write

Default value: TRUE

The “enable-undo” property

  “enable-undo”              gboolean

If undo/redo should be enabled for the editable.

Owner: GtkEditable

Flags: Read / Write

Default value: TRUE

The “max-width-chars” property

  “max-width-chars”          int

The desired maximum width of the entry, in characters.

Owner: GtkEditable

Flags: Read / Write

Allowed values: >= -1

Default value: -1

The “selection-bound” property

  “selection-bound”          int

The position of the opposite end of the selection from the cursor in chars.

Owner: GtkEditable

Flags: Read

Allowed values: [0,65535]

Default value: 0

The “text” property

  “text”                     char *

The contents of the entry.

Owner: GtkEditable

Flags: Read / Write

Default value: ""

The “width-chars” property

  “width-chars”              int

Number of characters to leave space for in the entry.

Owner: GtkEditable

Flags: Read / Write

Allowed values: >= -1

Default value: -1

The “xalign” property

  “xalign”                   float

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

Owner: GtkEditable

Flags: Read / Write

Allowed values: [0,1]

Default value: 0

The “changed” signal

void
user_function (GtkEditable *editable,
               gpointer     user_data)

The ::changed signal is emitted at the end of a single user-visible operation on the contents of the GtkEditable.

E.g., a paste operation that replaces the contents of the selection will cause only one signal emission (even though it is implemented by first deleting the selection, then inserting the new content, and may cause multiple ::notify::text signals to be emitted).

Flags: Run Last

The “delete-text” signal

void
user_function (GtkEditable *editable,
               int          start_pos,
               int          end_pos,
               gpointer     user_data)

This signal is emitted when text is deleted from the widget by the user. The default handler for this signal will normally be responsible for deleting the text, so by connecting to this signal and then stopping the signal with g_signal_stop_emission(), it is possible to modify the range of deleted text, or prevent it from being deleted entirely. The start_pos and end_pos parameters are interpreted as for gtk_editable_delete_text().

Flags: Run Last

The “insert-text” signal

void
user_function (GtkEditable *editable,
               char        *text,
               int          length,
               gpointer     position,
               gpointer     user_data)

This signal is emitted when text is inserted into the widget by the user. The default handler for this signal will normally be responsible for inserting the text, so by connecting to this signal and then stopping the signal with g_signal_stop_emission(), it is possible to modify the inserted text, or prevent it from being inserted entirely.

Flags: Run Last