<< Back to man.ChinaUnix.net

<< Back to man.ChinaUnix.net

GtkEditable

GtkEditable — Interface for text-editing widgets

Synopsis


#include <gtk/gtk.h>


            GtkEditable;
void        gtk_editable_select_region      (GtkEditable *editable,
                                             gint start,
                                             gint end);
gboolean    gtk_editable_get_selection_bounds
                                            (GtkEditable *editable,
                                             gint *start,
                                             gint *end);
void        gtk_editable_insert_text        (GtkEditable *editable,
                                             const gchar *new_text,
                                             gint new_text_length,
                                             gint *position);
void        gtk_editable_delete_text        (GtkEditable *editable,
                                             gint start_pos,
                                             gint end_pos);
gchar*      gtk_editable_get_chars          (GtkEditable *editable,
                                             gint start_pos,
                                             gint end_pos);
void        gtk_editable_cut_clipboard      (GtkEditable *editable);
void        gtk_editable_copy_clipboard     (GtkEditable *editable);
void        gtk_editable_paste_clipboard    (GtkEditable *editable);
void        gtk_editable_delete_selection   (GtkEditable *editable);
void        gtk_editable_set_position       (GtkEditable *editable,
                                             gint position);
gint        gtk_editable_get_position       (GtkEditable *editable);
void        gtk_editable_set_editable       (GtkEditable *editable,
                                             gboolean is_editable);
gboolean    gtk_editable_get_editable       (GtkEditable *editable);


Object Hierarchy


  GInterface
   +----GtkEditable

Known Implementations

GtkEditable is implemented by GtkEntry, GtkOldEditable, GtkSpinButton and GtkText.

Signal Prototypes


"changed"   void        user_function      (GtkEditable *editable,
                                            gpointer user_data);
"delete-text"
            void        user_function      (GtkEditable *editable,
                                            gint start_pos,
                                            gint end_pos,
                                            gpointer user_data);
"insert-text"
            void        user_function      (GtkEditable *editable,
                                            gchar *new_text,
                                            gint new_text_length,
                                            gint *position,
                                            gpointer user_data);

Description

The GtkEditable interface is an interface which should be implemented by text editing widgets, such as GtkEntry and GtkText. 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 to modify the behavior of a widget.

As an example of the latter usage, by connecting the following handler to "insert_text", an application can convert all entry into a widget into uppercase.

Example 3. Forcing entry to uppercase.

include <ctype.h>

void
insert_text_handler (GtkEditable *editable,
                     const gchar *text,
                     gint         length,
                     gint        *position,
                     gpointer     data)
{
  int i;
  gchar *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);
}

Details

GtkEditable

typedef struct _GtkEditable GtkEditable;

The GtkEditable structure contains the following fields. (These fields should be considered read-only. They should never be set by an application.)

guint selection_start;the starting position of the selected characters in the widget.
guint selection_end;the end position of the selected characters in the widget.
guint editable;a flag indicating whether or not the widget is editable by the user.


gtk_editable_select_region ()

void        gtk_editable_select_region      (GtkEditable *editable,
                                             gint start,
                                             gint end);

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 the characters selected will be those characters from start_pos to the end of the text.

editable :a GtkEditable widget.
start :the starting position.
end :the end position.

gtk_editable_get_selection_bounds ()

gboolean    gtk_editable_get_selection_bounds
                                            (GtkEditable *editable,
                                             gint *start,
                                             gint *end);

Gets the current selection bounds, if there is a selection.

editable :a GtkEditable widget.
start :location to store the starting position, or NULL.
end :location to store the end position, or NULL.
Returns :TRUE if there is a selection.

gtk_editable_insert_text ()

void        gtk_editable_insert_text        (GtkEditable *editable,
                                             const gchar *new_text,
                                             gint new_text_length,
                                             gint *position);

Inserts text at a given position.

editable :a GtkEditable widget.
new_text :the text to insert.
new_text_length :the length of the text to insert, in bytes
position :an inout parameter. The caller initializes it to the position at which to insert the text. After the call it points at the position after the newly inserted text.

gtk_editable_delete_text ()

void        gtk_editable_delete_text        (GtkEditable *editable,
                                             gint start_pos,
                                             gint 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 the characters deleted will be those characters from start_pos to the end of the text.

editable :a GtkEditable widget.
start_pos :the starting position.
end_pos :the end position.

gtk_editable_get_chars ()

gchar*      gtk_editable_get_chars          (GtkEditable *editable,
                                             gint start_pos,
                                             gint 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 the characters retrieved will be those characters from start_pos to the end of the text.

editable :a GtkEditable widget.
start_pos :the starting position.
end_pos :the end position.
Returns :the characters in the indicated region. The result must be freed with g_free() when the application is finished with it.

gtk_editable_cut_clipboard ()

void        gtk_editable_cut_clipboard      (GtkEditable *editable);

Causes the characters in the current selection to be copied to the clipboard and then deleted from the widget.

editable :a GtkEditable widget.

gtk_editable_copy_clipboard ()

void        gtk_editable_copy_clipboard     (GtkEditable *editable);

Causes the characters in the current selection to be copied to the clipboard.

editable :a GtkEditable widget.

gtk_editable_paste_clipboard ()

void        gtk_editable_paste_clipboard    (GtkEditable *editable);

Causes the contents of the clipboard to be pasted into the given widget at the current cursor position.

editable :a GtkEditable widget.

gtk_editable_delete_selection ()

void        gtk_editable_delete_selection   (GtkEditable *editable);

Deletes the current contents of the widgets selection and disclaims the selection.

editable :a GtkEditable widget.

gtk_editable_set_position ()

void        gtk_editable_set_position       (GtkEditable *editable,
                                             gint position);

Sets the cursor position.

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

gtk_editable_get_position ()

gint        gtk_editable_get_position       (GtkEditable *editable);

Retrieves the current cursor position.

editable :a GtkEditable widget.
Returns :the position of the cursor. The cursor is displayed before the character with the given (base 0) index in the widget. The value will be less than or equal to the number of characters in the widget. 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.

editable :a GtkEditable widget.
is_editable :TRUE if the user is allowed to edit the text in the widget.

gtk_editable_get_editable ()

gboolean    gtk_editable_get_editable       (GtkEditable *editable);

Retrieves whether editable is editable. See gtk_editable_set_editable().

editable : a GtkEditable
Returns : TRUE if editable is editable.

Signals

The "changed" signal

void        user_function                  (GtkEditable *editable,
                                            gpointer user_data);

Indicates that the user has changed the contents of the widget.

editable :the object which received the signal.
user_data :user data set when the signal handler was connected.

The "delete-text" signal

void        user_function                  (GtkEditable *editable,
                                            gint start_pos,
                                            gint 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 inserting the text, so by connecting to this signal and then stopping the signal with gtk_signal_emit_stop(), it is possible to modify the inserted text, or prevent it from being inserted entirely. The start_pos and end_pos parameters are interpreted as for gtk_editable_delete_text()

editable :the object which received the signal.
start_pos :the starting position.
end_pos :the end position.
user_data :user data set when the signal handler was connected.

The "insert-text" signal

void        user_function                  (GtkEditable *editable,
                                            gchar *new_text,
                                            gint new_text_length,
                                            gint *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 gtk_signal_emit_stop(), it is possible to modify the inserted text, or prevent it from being inserted entirely.

editable :the object which received the signal.
new_text :the new text to insert.
new_text_length :the length of the new text.
position :the position at which to insert the new text. this is an in-out paramter. After the signal emission is finished, it should point after the newly inserted text.
user_data :user data set when the signal handler was connected.