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2023-12-12 11:36:42 +01:00
/* GTK - The GIMP Toolkit
* Copyright (C) 2000 Red Hat, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*/
#include "config.h"
#include <string.h>
#include "gtkimcontext.h"
#include "gtkimcontextprivate.h"
#include "gtkprivate.h"
#include "gtktypebuiltins.h"
#include "gtkmarshalers.h"
#include "gdk/gdkeventsprivate.h"
/**
* GtkIMContext:
*
* `GtkIMContext` defines the interface for GTK input methods.
*
* `GtkIMContext` is used by GTK text input widgets like `GtkText`
* to map from key events to Unicode character strings.
*
* An input method may consume multiple key events in sequence before finally
* outputting the composed result. This is called *preediting*, and an input
* method may provide feedback about this process by displaying the intermediate
* composition states as preedit text. To do so, the `GtkIMContext` will emit
* [signal@Gtk.IMContext::preedit-start], [signal@Gtk.IMContext::preedit-changed]
* and [signal@Gtk.IMContext::preedit-end] signals.
*
* For instance, the built-in GTK input method [class@Gtk.IMContextSimple]
* implements the input of arbitrary Unicode code points by holding down the
* <kbd>Control</kbd> and <kbd>Shift</kbd> keys and then typing <kbd>u</kbd>
* followed by the hexadecimal digits of the code point. When releasing the
* <kbd>Control</kbd> and <kbd>Shift</kbd> keys, preediting ends and the
* character is inserted as text. For example,
*
* Ctrl+Shift+u 2 0 A C
*
* results in the € sign.
*
* Additional input methods can be made available for use by GTK widgets as
* loadable modules. An input method module is a small shared library which
* provides a `GIOExtension` for the extension point named "gtk-im-module".
*
* To connect a widget to the users preferred input method, you should use
* [class@Gtk.IMMulticontext].
*/
enum {
PREEDIT_START,
PREEDIT_END,
PREEDIT_CHANGED,
COMMIT,
RETRIEVE_SURROUNDING,
DELETE_SURROUNDING,
LAST_SIGNAL
};
enum {
PROP_INPUT_PURPOSE = 1,
PROP_INPUT_HINTS,
LAST_PROPERTY
};
static guint im_context_signals[LAST_SIGNAL] = { 0, };
static GParamSpec *properties[LAST_PROPERTY] = { NULL, };
typedef struct _GtkIMContextPrivate GtkIMContextPrivate;
struct _GtkIMContextPrivate {
GtkInputPurpose purpose;
GtkInputHints hints;
};
static void gtk_im_context_real_get_preedit_string (GtkIMContext *context,
char **str,
PangoAttrList **attrs,
int *cursor_pos);
static gboolean gtk_im_context_real_filter_keypress (GtkIMContext *context,
GdkEvent *event);
static gboolean gtk_im_context_real_get_surrounding_with_selection
(GtkIMContext *context,
char **text,
int *cursor_index,
int *selection_bound);
static void gtk_im_context_real_set_surrounding_with_selection
(GtkIMContext *context,
const char *text,
int len,
int cursor_index,
int selection_bound);
static void gtk_im_context_get_property (GObject *obj,
guint property_id,
GValue *value,
GParamSpec *pspec);
static void gtk_im_context_set_property (GObject *obj,
guint property_id,
const GValue *value,
GParamSpec *pspec);
G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (GtkIMContext, gtk_im_context, G_TYPE_OBJECT)
/**
* GtkIMContextClass:
* @preedit_start: Default handler of the [signal@Gtk.IMContext::preedit-start] signal.
* @preedit_end: Default handler of the [signal@Gtk.IMContext::preedit-end] signal.
* @preedit_changed: Default handler of the [signal@Gtk.IMContext::preedit-changed]
* signal.
* @commit: Default handler of the [signal@Gtk.IMContext::commit] signal.
* @retrieve_surrounding: Default handler of the
* [signal@Gtk.IMContext::retrieve-surrounding] signal.
* @delete_surrounding: Default handler of the
* [signal@Gtk.IMContext::delete-surrounding] signal.
* @set_client_widget: Called via [method@Gtk.IMContext.set_client_widget] when
* the input window where the entered text will appear changes. Override this
* to keep track of the current input window, for instance for the purpose of
* positioning a status display of your input method.
* @get_preedit_string: Called via [method@Gtk.IMContext.get_preedit_string]
* to retrieve the text currently being preedited for display at the cursor
* position. Any input method which composes complex characters or any
* other compositions from multiple sequential key presses should override
* this method to provide feedback.
* @filter_keypress: Called via [method@Gtk.IMContext.filter_keypress] on every
* key press or release event. Every non-trivial input method needs to
* override this in order to implement the mapping from key events to text.
* A return value of %TRUE indicates to the caller that the event was
* consumed by the input method. In that case, the [signal@Gtk.IMContext::commit]
* signal should be emitted upon completion of a key sequence to pass the
* resulting text back to the input widget. Alternatively, %FALSE may be
* returned to indicate that the event wasn’t handled by the input method.
* If a builtin mapping exists for the key, it is used to produce a
* character.
* @focus_in: Called via [method@Gtk.IMContext.focus_in] when the input widget
* has gained focus. May be overridden to keep track of the current focus.
* @focus_out: Called via [method@Gtk.IMContext.focus_out] when the input widget
* has lost focus. May be overridden to keep track of the current focus.
* @reset: Called via [method@Gtk.IMContext.reset] to signal a change such as a
* change in cursor position. An input method that implements preediting
* should override this method to clear the preedit state on reset.
* @set_cursor_location: Called via [method@Gtk.IMContext.set_cursor_location]
* to inform the input method of the current cursor location relative to
* the client window. May be overridden to implement the display of popup
* windows at the cursor position.
* @set_use_preedit: Called via [method@Gtk.IMContext.set_use_preedit] to control
* the use of the preedit string. Override this to display feedback by some
* other means if turned off.
* @set_surrounding: Called via [method@Gtk.IMContext.set_surrounding] in
* response to [signal@Gtk.IMContext::retrieve-surrounding] signal to update
* the input method’s idea of the context around the cursor. It is not necessary
* to override this method even with input methods which implement
* context-dependent behavior. The base implementation is sufficient for
* [method@Gtk.IMContext.get_surrounding] to work.
* @get_surrounding: Called via [method@Gtk.IMContext.get_surrounding] to update
* the context around the cursor location. It is not necessary to override this
* method even with input methods which implement context-dependent behavior.
* The base implementation emits [signal@Gtk.IMContext::retrieve-surrounding]
* and records the context received by the subsequent invocation of
* [vfunc@Gtk.IMContext.get_surrounding].
* @set_surrounding_with_selection: Called via
* [method@Gtk.IMContext.set_surrounding_with_selection] in response to the
* [signal@Gtk.IMContext::retrieve-surrounding] signal to update the input
* method’s idea of the context around the cursor. It is not necessary to
* override this method even with input methods which implement
* context-dependent behavior. The base implementation is sufficient for
* [method@Gtk.IMContext.get_surrounding] to work.
* @get_surrounding_with_selection: Called via
* [method@Gtk.IMContext.get_surrounding_with_selection] to update the
* context around the cursor location. It is not necessary to override
* this method even with input methods which implement context-dependent
* behavior. The base implementation emits
* [signal@Gtk.IMContext::retrieve-surrounding] and records the context
* received by the subsequent invocation of [vfunc@Gtk.IMContext.get_surrounding].
*/
static void
gtk_im_context_class_init (GtkIMContextClass *klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
object_class->get_property = gtk_im_context_get_property;
object_class->set_property = gtk_im_context_set_property;
klass->get_preedit_string = gtk_im_context_real_get_preedit_string;
klass->filter_keypress = gtk_im_context_real_filter_keypress;
klass->get_surrounding_with_selection = gtk_im_context_real_get_surrounding_with_selection;
klass->set_surrounding_with_selection = gtk_im_context_real_set_surrounding_with_selection;
/**
* GtkIMContext::preedit-start:
* @context: the object on which the signal is emitted
*
* The ::preedit-start signal is emitted when a new preediting sequence
* starts.
*/
im_context_signals[PREEDIT_START] =
g_signal_new (I_("preedit-start"),
G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GtkIMContextClass, preedit_start),
NULL, NULL,
NULL,
G_TYPE_NONE, 0);
/**
* GtkIMContext::preedit-end:
* @context: the object on which the signal is emitted
*
* The ::preedit-end signal is emitted when a preediting sequence
* has been completed or canceled.
*/
im_context_signals[PREEDIT_END] =
g_signal_new (I_("preedit-end"),
G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GtkIMContextClass, preedit_end),
NULL, NULL,
NULL,
G_TYPE_NONE, 0);
/**
* GtkIMContext::preedit-changed:
* @context: the object on which the signal is emitted
*
* The ::preedit-changed signal is emitted whenever the preedit sequence
* currently being entered has changed.
*
* It is also emitted at the end of a preedit sequence, in which case
* [method@Gtk.IMContext.get_preedit_string] returns the empty string.
*/
im_context_signals[PREEDIT_CHANGED] =
g_signal_new (I_("preedit-changed"),
G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GtkIMContextClass, preedit_changed),
NULL, NULL,
NULL,
G_TYPE_NONE, 0);
/**
* GtkIMContext::commit:
* @context: the object on which the signal is emitted
* @str: the completed character(s) entered by the user
*
* The ::commit signal is emitted when a complete input sequence
* has been entered by the user.
*
* If the commit comes after a preediting sequence, the
* ::commit signal is emitted after ::preedit-end.
*
* This can be a single character immediately after a key press or
* the final result of preediting.
*/
im_context_signals[COMMIT] =
g_signal_new (I_("commit"),
G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GtkIMContextClass, commit),
NULL, NULL,
NULL,
G_TYPE_NONE, 1,
G_TYPE_STRING);
/**
* GtkIMContext::retrieve-surrounding:
* @context: the object on which the signal is emitted
*
* The ::retrieve-surrounding signal is emitted when the input method
* requires the context surrounding the cursor.
*
* The callback should set the input method surrounding context by
* calling the [method@Gtk.IMContext.set_surrounding] method.
*
* Returns: %TRUE if the signal was handled.
*/
im_context_signals[RETRIEVE_SURROUNDING] =
g_signal_new (I_("retrieve-surrounding"),
G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GtkIMContextClass, retrieve_surrounding),
_gtk_boolean_handled_accumulator, NULL,
_gtk_marshal_BOOLEAN__VOID,
G_TYPE_BOOLEAN, 0);
g_signal_set_va_marshaller (im_context_signals[RETRIEVE_SURROUNDING],
G_TYPE_FROM_CLASS (klass),
_gtk_marshal_BOOLEAN__VOIDv);
/**
* GtkIMContext::delete-surrounding:
* @context: the object on which the signal is emitted
* @offset: the character offset from the cursor position of the text
* to be deleted. A negative value indicates a position before
* the cursor.
* @n_chars: the number of characters to be deleted
*
* The ::delete-surrounding signal is emitted when the input method
* needs to delete all or part of the context surrounding the cursor.
*
* Returns: %TRUE if the signal was handled.
*/
im_context_signals[DELETE_SURROUNDING] =
g_signal_new (I_("delete-surrounding"),
G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GtkIMContextClass, delete_surrounding),
_gtk_boolean_handled_accumulator, NULL,
_gtk_marshal_BOOLEAN__INT_INT,
G_TYPE_BOOLEAN, 2,
G_TYPE_INT,
G_TYPE_INT);
g_signal_set_va_marshaller (im_context_signals[DELETE_SURROUNDING],
G_TYPE_FROM_CLASS (klass),
_gtk_marshal_BOOLEAN__INT_INTv);
/**
* GtkIMContext:input-purpose:
*
* The purpose of the text field that the `GtkIMContext is connected to.
*
* This property can be used by on-screen keyboards and other input
* methods to adjust their behaviour.
*/
properties[PROP_INPUT_PURPOSE] =
g_param_spec_enum ("input-purpose", NULL, NULL,
GTK_TYPE_INPUT_PURPOSE,
GTK_INPUT_PURPOSE_FREE_FORM,
G_PARAM_READWRITE|G_PARAM_STATIC_STRINGS|G_PARAM_EXPLICIT_NOTIFY);
/**
* GtkIMContext:input-hints:
*
* Additional hints that allow input methods to fine-tune
* their behaviour.
*/
properties[PROP_INPUT_HINTS] =
g_param_spec_flags ("input-hints", NULL, NULL,
GTK_TYPE_INPUT_HINTS,
GTK_INPUT_HINT_NONE,
G_PARAM_READWRITE|G_PARAM_STATIC_STRINGS|G_PARAM_EXPLICIT_NOTIFY);
g_object_class_install_properties (object_class, LAST_PROPERTY, properties);
}
static void
gtk_im_context_init (GtkIMContext *im_context)
{
}
static void
gtk_im_context_real_get_preedit_string (GtkIMContext *context,
char **str,
PangoAttrList **attrs,
int *cursor_pos)
{
if (str)
*str = g_strdup ("");
if (attrs)
*attrs = pango_attr_list_new ();
if (cursor_pos)
*cursor_pos = 0;
}
static gboolean
gtk_im_context_real_filter_keypress (GtkIMContext *context,
GdkEvent *event)
{
return FALSE;
}
typedef struct
{
char *text;
int cursor_index;
int selection_bound;
} SurroundingInfo;
static void
gtk_im_context_real_set_surrounding_with_selection (GtkIMContext *context,
const char *text,
int len,
int cursor_index,
int selection_bound)
{
SurroundingInfo *info = g_object_get_data (G_OBJECT (context),
"gtk-im-surrounding-info");
if (info)
{
g_free (info->text);
info->text = g_strndup (text, len);
info->cursor_index = cursor_index;
info->selection_bound = selection_bound;
}
}
static gboolean
gtk_im_context_real_get_surrounding_with_selection (GtkIMContext *context,
char **text,
int *cursor_index,
int *selection_bound)
{
gboolean result;
gboolean info_is_local = FALSE;
SurroundingInfo local_info = { NULL, 0 };
SurroundingInfo *info;
info = g_object_get_data (G_OBJECT (context), "gtk-im-surrounding-info");
if (!info)
{
info = &local_info;
g_object_set_data (G_OBJECT (context), I_("gtk-im-surrounding-info"), info);
info_is_local = TRUE;
}
g_signal_emit (context,
im_context_signals[RETRIEVE_SURROUNDING], 0,
&result);
if (result)
{
*text = g_strdup (info->text ? info->text : "");
*cursor_index = info->cursor_index;
*selection_bound = info->selection_bound;
}
else
{
*text = NULL;
*cursor_index = 0;
*selection_bound = 0;
}
if (info_is_local)
{
g_free (info->text);
g_object_set_data (G_OBJECT (context), I_("gtk-im-surrounding-info"), NULL);
}
return result;
}
/**
* gtk_im_context_set_client_widget:
* @context: a `GtkIMContext`
* @widget: (nullable): the client widget. This may be %NULL to indicate
* that the previous client widget no longer exists.
*
* Set the client widget for the input context.
*
* This is the `GtkWidget` holding the input focus. This widget is
* used in order to correctly position status windows, and may
* also be used for purposes internal to the input method.
*/
void
gtk_im_context_set_client_widget (GtkIMContext *context,
GtkWidget *widget)
{
GtkIMContextClass *klass;
g_return_if_fail (GTK_IS_IM_CONTEXT (context));
klass = GTK_IM_CONTEXT_GET_CLASS (context);
if (klass->set_client_widget)
klass->set_client_widget (context, widget);
}
/**
* gtk_im_context_get_preedit_string:
* @context: a `GtkIMContext`
* @str: (out) (transfer full): location to store the retrieved
* string. The string retrieved must be freed with g_free().
* @attrs: (out) (transfer full): location to store the retrieved
* attribute list. When you are done with this list, you
* must unreference it with [method@Pango.AttrList.unref].
* @cursor_pos: (out): location to store position of cursor
* (in characters) within the preedit string.
*
* Retrieve the current preedit string for the input context,
* and a list of attributes to apply to the string.
*
* This string should be displayed inserted at the insertion point.
*/
void
gtk_im_context_get_preedit_string (GtkIMContext *context,
char **str,
PangoAttrList **attrs,
int *cursor_pos)
{
GtkIMContextClass *klass;
g_return_if_fail (GTK_IS_IM_CONTEXT (context));
klass = GTK_IM_CONTEXT_GET_CLASS (context);
klass->get_preedit_string (context, str, attrs, cursor_pos);
g_return_if_fail (str == NULL || g_utf8_validate (*str, -1, NULL));
}
/**
* gtk_im_context_filter_keypress:
* @context: a `GtkIMContext`
* @event: the key event
*
* Allow an input method to internally handle key press and release
* events.
*
* If this function returns %TRUE, then no further processing
* should be done for this key event.
*
* Returns: %TRUE if the input method handled the key event.
*/
gboolean
gtk_im_context_filter_keypress (GtkIMContext *context,
GdkEvent *key)
{
GtkIMContextClass *klass;
g_return_val_if_fail (GTK_IS_IM_CONTEXT (context), FALSE);
g_return_val_if_fail (key != NULL, FALSE);
klass = GTK_IM_CONTEXT_GET_CLASS (context);
return klass->filter_keypress (context, key);
}
/**
* gtk_im_context_filter_key:
* @context: a `GtkIMContext`
* @press: whether to forward a key press or release event
* @surface: the surface the event is for
* @device: the device that the event is for
* @time: the timestamp for the event
* @keycode: the keycode for the event
* @state: modifier state for the event
* @group: the active keyboard group for the event
*
* Allow an input method to forward key press and release events
* to another input method without necessarily having a `GdkEvent`
* available.
*
* Returns: %TRUE if the input method handled the key event.
*/
gboolean
gtk_im_context_filter_key (GtkIMContext *context,
gboolean press,
GdkSurface *surface,
GdkDevice *device,
guint32 time,
guint keycode,
GdkModifierType state,
int group)
{
GdkTranslatedKey translated, no_lock;
GdkEvent *key;
gboolean ret;
guint keyval;
int layout;
int level;
GdkModifierType consumed;
g_return_val_if_fail (GTK_IS_IM_CONTEXT (context), FALSE);
if (!gdk_display_translate_key (gdk_surface_get_display (surface),
keycode,
state,
group,
&keyval,
&layout,
&level,
&consumed))
return FALSE;
translated.keyval = keyval;
translated.layout = layout;
translated.level = level;
translated.consumed = consumed;
if (!gdk_display_translate_key (gdk_surface_get_display (surface),
keycode,
state & ~GDK_LOCK_MASK,
group,
&keyval,
&layout,
&level,
&consumed))
return FALSE;
no_lock.keyval = keyval;
no_lock.layout = layout;
no_lock.level = level;
no_lock.consumed = consumed;
key = gdk_key_event_new (press ? GDK_KEY_PRESS : GDK_KEY_RELEASE,
surface,
device,
time,
keycode,
state,
FALSE, /* FIXME */
&translated,
&no_lock,
NULL);
ret = GTK_IM_CONTEXT_GET_CLASS (context)->filter_keypress (context, key);
gdk_event_unref (key);
return ret;
}
/**
* gtk_im_context_focus_in:
* @context: a `GtkIMContext`
*
* Notify the input method that the widget to which this
* input context corresponds has gained focus.
*
* The input method may, for example, change the displayed
* feedback to reflect this change.
*/
void
gtk_im_context_focus_in (GtkIMContext *context)
{
GtkIMContextClass *klass;
g_return_if_fail (GTK_IS_IM_CONTEXT (context));
klass = GTK_IM_CONTEXT_GET_CLASS (context);
if (klass->focus_in)
klass->focus_in (context);
}
/**
* gtk_im_context_focus_out:
* @context: a `GtkIMContext`
*
* Notify the input method that the widget to which this
* input context corresponds has lost focus.
*
* The input method may, for example, change the displayed
* feedback or reset the contexts state to reflect this change.
*/
void
gtk_im_context_focus_out (GtkIMContext *context)
{
GtkIMContextClass *klass;
g_return_if_fail (GTK_IS_IM_CONTEXT (context));
klass = GTK_IM_CONTEXT_GET_CLASS (context);
if (klass->focus_out)
klass->focus_out (context);
}
/**
* gtk_im_context_reset:
* @context: a `GtkIMContext`
*
* Notify the input method that a change such as a change in cursor
* position has been made.
*
* This will typically cause the input method to clear the preedit state.
*/
void
gtk_im_context_reset (GtkIMContext *context)
{
GtkIMContextClass *klass;
g_return_if_fail (GTK_IS_IM_CONTEXT (context));
klass = GTK_IM_CONTEXT_GET_CLASS (context);
if (klass->reset)
klass->reset (context);
}
/**
* gtk_im_context_set_cursor_location:
* @context: a `GtkIMContext`
* @area: new location
*
* Notify the input method that a change in cursor
* position has been made.
*
* The location is relative to the client widget.
*/
void
gtk_im_context_set_cursor_location (GtkIMContext *context,
const GdkRectangle *area)
{
GtkIMContextClass *klass;
g_return_if_fail (GTK_IS_IM_CONTEXT (context));
klass = GTK_IM_CONTEXT_GET_CLASS (context);
if (klass->set_cursor_location)
klass->set_cursor_location (context, (GdkRectangle *) area);
}
/**
* gtk_im_context_set_use_preedit:
* @context: a `GtkIMContext`
* @use_preedit: whether the IM context should use the preedit string.
*
* Sets whether the IM context should use the preedit string
* to display feedback.
*
* If @use_preedit is %FALSE (default is %TRUE), then the IM context
* may use some other method to display feedback, such as displaying
* it in a child of the root window.
*/
void
gtk_im_context_set_use_preedit (GtkIMContext *context,
gboolean use_preedit)
{
GtkIMContextClass *klass;
g_return_if_fail (GTK_IS_IM_CONTEXT (context));
klass = GTK_IM_CONTEXT_GET_CLASS (context);
if (klass->set_use_preedit)
klass->set_use_preedit (context, use_preedit);
}
/**
* gtk_im_context_set_surrounding:
* @context: a `GtkIMContext`
* @text: text surrounding the insertion point, as UTF-8.
* the preedit string should not be included within @text
* @len: the length of @text, or -1 if @text is nul-terminated
* @cursor_index: the byte index of the insertion cursor within @text.
*
* Sets surrounding context around the insertion point and preedit
* string.
*
* This function is expected to be called in response to the
* [signal@Gtk.IMContext::retrieve-surrounding] signal, and will
* likely have no effect if called at other times.
*
* Deprecated: 4.2: Use [method@Gtk.IMContext.set_surrounding_with_selection] instead
*/
void
gtk_im_context_set_surrounding (GtkIMContext *context,
const char *text,
int len,
int cursor_index)
{
gtk_im_context_set_surrounding_with_selection (context, text, len, cursor_index, cursor_index);
}
/**
* gtk_im_context_set_surrounding_with_selection:
* @context: a `GtkIMContext`
* @text: text surrounding the insertion point, as UTF-8.
* the preedit string should not be included within @text
* @len: the length of @text, or -1 if @text is nul-terminated
* @cursor_index: the byte index of the insertion cursor within @text
* @anchor_index: the byte index of the selection bound within @text
*
* Sets surrounding context around the insertion point and preedit
* string. This function is expected to be called in response to the
* [signal@Gtk.IMContext::retrieve_surrounding] signal, and will likely
* have no effect if called at other times.
*
* Since: 4.2
*/
void
gtk_im_context_set_surrounding_with_selection (GtkIMContext *context,
const char *text,
int len,
int cursor_index,
int anchor_index)
{
GtkIMContextClass *klass;
g_return_if_fail (GTK_IS_IM_CONTEXT (context));
g_return_if_fail (text != NULL || len == 0);
if (text == NULL && len == 0)
text = "";
if (len < 0)
len = strlen (text);
g_return_if_fail (cursor_index >= 0 && cursor_index <= len);
klass = GTK_IM_CONTEXT_GET_CLASS (context);
if (klass->set_surrounding_with_selection)
klass->set_surrounding_with_selection (context, text, len, cursor_index, anchor_index);
else if (klass->set_surrounding)
klass->set_surrounding (context, text, len, cursor_index);
}
/**
* gtk_im_context_get_surrounding:
* @context: a `GtkIMContext`
* @text: (out) (transfer full): location to store a UTF-8 encoded
* string of text holding context around the insertion point.
* If the function returns %TRUE, then you must free the result
* stored in this location with g_free().
* @cursor_index: (out): location to store byte index of the insertion
* cursor within @text.
*
* Retrieves context around the insertion point.
*
* Input methods typically want context in order to constrain input text
* based on existing text; this is important for languages such as Thai
* where only some sequences of characters are allowed.
*
* This function is implemented by emitting the
* [signal@Gtk.IMContext::retrieve-surrounding] signal on the input method;
* in response to this signal, a widget should provide as much context as
* is available, up to an entire paragraph, by calling
* [method@Gtk.IMContext.set_surrounding].
*
* Note that there is no obligation for a widget to respond to the
* `::retrieve-surrounding` signal, so input methods must be prepared to
* function without context.
*
* Returns: `TRUE` if surrounding text was provided; in this case
* you must free the result stored in `text`.
*
* Deprecated: 4.2: Use [method@Gtk.IMContext.get_surrounding_with_selection] instead.
*/
gboolean
gtk_im_context_get_surrounding (GtkIMContext *context,
char **text,
int *cursor_index)
{
return gtk_im_context_get_surrounding_with_selection (context,
text,
cursor_index,
NULL);
}
/**
* gtk_im_context_get_surrounding_with_selection:
* @context: a `GtkIMContext`
* @text: (out) (transfer full): location to store a UTF-8 encoded
* string of text holding context around the insertion point.
* If the function returns %TRUE, then you must free the result
* stored in this location with g_free().
* @cursor_index: (out): location to store byte index of the insertion
* cursor within @text.
* @anchor_index: (out): location to store byte index of the selection
* bound within @text
*
* Retrieves context around the insertion point.
*
* Input methods typically want context in order to constrain input
* text based on existing text; this is important for languages such
* as Thai where only some sequences of characters are allowed.
*
* This function is implemented by emitting the
* [signal@Gtk.IMContext::retrieve-surrounding] signal on the input method;
* in response to this signal, a widget should provide as much context as
* is available, up to an entire paragraph, by calling
* [method@Gtk.IMContext.set_surrounding_with_selection].
*
* Note that there is no obligation for a widget to respond to the
* `::retrieve-surrounding` signal, so input methods must be prepared to
* function without context.
*
* Returns: `TRUE` if surrounding text was provided; in this case
* you must free the result stored in `text`.
*
* Since: 4.2
*/
gboolean
gtk_im_context_get_surrounding_with_selection (GtkIMContext *context,
char **text,
int *cursor_index,
int *anchor_index)
{
GtkIMContextClass *klass;
char *local_text = NULL;
int local_index;
gboolean result = FALSE;
g_return_val_if_fail (GTK_IS_IM_CONTEXT (context), FALSE);
klass = GTK_IM_CONTEXT_GET_CLASS (context);
if (klass->get_surrounding_with_selection)
result = klass->get_surrounding_with_selection
(context,
text ? text : &local_text,
cursor_index ? cursor_index : &local_index,
anchor_index ? anchor_index : &local_index);
else if (klass->get_surrounding)
{
result = klass->get_surrounding (context,
text ? text : &local_text,
&local_index);
if (cursor_index)
*cursor_index = local_index;
if (anchor_index)
*anchor_index = local_index;
}
if (result)
g_free (local_text);
return result;
}
/**
* gtk_im_context_delete_surrounding:
* @context: a `GtkIMContext`
* @offset: offset from cursor position in chars;
* a negative value means start before the cursor.
* @n_chars: number of characters to delete.
*
* Asks the widget that the input context is attached to delete
* characters around the cursor position by emitting the
* `::delete_surrounding` signal.
*
* Note that @offset and @n_chars are in characters not in bytes
* which differs from the usage other places in `GtkIMContext`.
*
* In order to use this function, you should first call
* [method@Gtk.IMContext.get_surrounding] to get the current context,
* and call this function immediately afterwards to make sure that you
* know what you are deleting. You should also account for the fact
* that even if the signal was handled, the input context might not
* have deleted all the characters that were requested to be deleted.
*
* This function is used by an input method that wants to make
* substitutions in the existing text in response to new input.
* It is not useful for applications.
*
* Returns: %TRUE if the signal was handled.
*/
gboolean
gtk_im_context_delete_surrounding (GtkIMContext *context,
int offset,
int n_chars)
{
gboolean result;
g_return_val_if_fail (GTK_IS_IM_CONTEXT (context), FALSE);
g_signal_emit (context,
im_context_signals[DELETE_SURROUNDING], 0,
offset, n_chars, &result);
return result;
}
static void
gtk_im_context_get_property (GObject *obj,
guint property_id,
GValue *value,
GParamSpec *pspec)
{
GtkIMContextPrivate *priv = gtk_im_context_get_instance_private (GTK_IM_CONTEXT (obj));
switch (property_id)
{
case PROP_INPUT_PURPOSE:
g_value_set_enum (value, priv->purpose);
break;
case PROP_INPUT_HINTS:
g_value_set_flags (value, priv->hints);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (obj, property_id, pspec);
break;
}
}
static void
gtk_im_context_set_property (GObject *obj,
guint property_id,
const GValue *value,
GParamSpec *pspec)
{
GtkIMContextPrivate *priv = gtk_im_context_get_instance_private (GTK_IM_CONTEXT (obj));
switch (property_id)
{
case PROP_INPUT_PURPOSE:
if (priv->purpose != g_value_get_enum (value))
{
priv->purpose = g_value_get_enum (value);
g_object_notify_by_pspec (obj, pspec);
}
break;
case PROP_INPUT_HINTS:
if (priv->hints != g_value_get_flags (value))
{
priv->hints = g_value_get_flags (value);
g_object_notify_by_pspec (obj, pspec);
}
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (obj, property_id, pspec);
break;
}
}
void
gtk_im_context_activate_osk (GtkIMContext *context)
{
g_return_if_fail (GTK_IS_IM_CONTEXT (context));
if (GTK_IM_CONTEXT_GET_CLASS (context)->activate_osk)
GTK_IM_CONTEXT_GET_CLASS (context)->activate_osk (context);
}