ecore_imf_example.c

- Main Page
- Related Pages
- Modules
- Namespaces
- Data Structures
- Files
- Examples

ecore_imf_example.c

Show how to write simple editor using the Ecore_IMF library

#include <Ecore.h>
#include <Ecore_Evas.h>
#include <Ecore_IMF.h>
#include <Ecore_IMF_Evas.h>
#include <Evas.h>
#include <stdio.h>
#define WIDTH 480
#define HEIGHT 800
typedef struct _Entry Entry;
struct _Entry
{
Evas_Object *rect;
Evas_Object *txt_obj;
Evas_Textblock_Style *txt_style;
Evas_Textblock_Cursor *cursor;
Evas_Textblock_Cursor *preedit_start;
Evas_Textblock_Cursor *preedit_end;
Ecore_IMF_Context *imf_context;
Eina_Bool have_preedit : 1;
};
static void _imf_cursor_info_set(Entry *en);
static void
_mouse_down_cb(void *data, Evas *e EINA_UNUSED, Evas_Object *o EINA_UNUSED, void *event_info)
{
Entry *en = data;
Evas_Event_Mouse_Down *ev = event_info;
if (!en) return;
if (en->imf_context)
{
Ecore_IMF_Event_Mouse_Down ecore_ev;
ecore_imf_evas_event_mouse_down_wrap(ev, &ecore_ev);
if (ecore_imf_context_filter_event(en->imf_context,
ECORE_IMF_EVENT_MOUSE_DOWN,
(Ecore_IMF_Event *)&ecore_ev))
return;
// ecore_imf_context_reset should be called before calculating new cursor position
ecore_imf_context_reset(en->imf_context);
}
// calculate new cursor position
}
static void
_mouse_up_cb(void *data, Evas *e EINA_UNUSED, Evas_Object *o EINA_UNUSED, void *event_info)
{
Entry *en = data;
Evas_Event_Mouse_Up *ev = event_info;
if (!en) return;
if (ev->event_flags & EVAS_EVENT_FLAG_ON_HOLD)
{
_imf_cursor_info_set(en);
return;
}
if (en->imf_context)
{
Ecore_IMF_Event_Mouse_Up ecore_ev;
ecore_imf_evas_event_mouse_up_wrap(ev, &ecore_ev);
if (ecore_imf_context_filter_event(en->imf_context,
ECORE_IMF_EVENT_MOUSE_UP,
(Ecore_IMF_Event *)&ecore_ev))
return;
}
if (evas_object_focus_get(en->rect))
{
// notify cursor information
_imf_cursor_info_set(en);
}
else
evas_object_focus_set(en->rect, EINA_TRUE);
}
static void
_entry_focus_in_cb(void *data, Evas *e EINA_UNUSED, Evas_Object *o EINA_UNUSED, void *event_info EINA_UNUSED)
{
Entry *en = data;
if (!en) return;
if (en->imf_context)
ecore_imf_context_focus_in(en->imf_context);
// notify the cursor information
_imf_cursor_info_set(en);
}
static void
_entry_focus_out_cb(void *data, Evas *e EINA_UNUSED, Evas_Object *o EINA_UNUSED, void *event_info EINA_UNUSED)
{
Entry *en = data;
if (!en) return;
if (en->imf_context)
{
// ecore_imf_context_reset should be called for flushing the preedit string in focus-out event handler
ecore_imf_context_reset(en->imf_context);
ecore_imf_context_focus_out(en->imf_context);
}
}
static void
_canvas_focus_in_cb(void *data EINA_UNUSED, Evas *e, void *event_info EINA_UNUSED)
{
Entry *en;
Evas_Object *obj = evas_focus_get(e);
if (!obj) return;
en = evas_object_data_get(obj, "Entry");
if (en)
_entry_focus_in_cb(en, NULL, NULL, NULL);
}
static void
_canvas_focus_out_cb(void *data EINA_UNUSED, Evas *e, void *event_info EINA_UNUSED)
{
Entry *en;
Evas_Object *obj = evas_focus_get(e);
if (!obj) return;
en = evas_object_data_get(obj, "Entry");
if (en)
_entry_focus_out_cb(en, NULL, NULL, NULL);
}
static void
_imf_cursor_info_set(Entry *en)
{
Evas_Coord x, y, w, h;
Evas_Coord cx, cy, cw, ch; // cursor geometry
int cursor_pos; // cursor position in chars (Not bytes)
Evas_BiDi_Direction dir;
if (!en) return;
// get cursor geometry
evas_object_geometry_get(en->txt_obj, &x, &y, &w, &h);
evas_textblock_cursor_geometry_get(en->cursor, &cx, &cy, &cw, &ch, &dir, EVAS_TEXTBLOCK_CURSOR_BEFORE);
// get cursor position
cursor_pos = evas_textblock_cursor_pos_get(en->cursor);
ecore_imf_context_cursor_position_set(en->imf_context, cursor_pos);
ecore_imf_context_cursor_location_set(en->imf_context, x + cx, y + cy, cw, ch);
ecore_imf_context_bidi_direction_set(en->imf_context, (Ecore_IMF_BiDi_Direction)dir);
}
static void
_preedit_del(Entry *en)
{
if (!en || !en->have_preedit) return;
if (!en->preedit_start || !en->preedit_end) return;
if (!evas_textblock_cursor_compare(en->preedit_start, en->preedit_end)) return;
// delete the preedit characters
evas_textblock_cursor_range_delete(en->preedit_start, en->preedit_end);
}
static void
_preedit_clear(Entry *en)
{
if (en->preedit_start)
{
evas_textblock_cursor_free(en->preedit_start);
en->preedit_start = NULL;
}
if (en->preedit_end)
{
evas_textblock_cursor_free(en->preedit_end);
en->preedit_end = NULL;
}
en->have_preedit = EINA_FALSE;
}
static Eina_Bool
_ecore_imf_retrieve_surrounding_cb(void *data, Ecore_IMF_Context *ctx EINA_UNUSED, char **text, int *cursor_pos)
{
// This callback will be called when the Input Method Context module requests the surrounding context.
Entry *en = data;
const char *str;
if (!en) return EINA_FALSE;
str = evas_object_textblock_text_markup_get(en->txt_obj);
if (text)
*text = str ? strdup(str) : strdup("");
// get the current position of cursor
if (cursor_pos)
*cursor_pos = evas_textblock_cursor_pos_get(en->cursor);
return EINA_TRUE;
}
static void
_ecore_imf_event_delete_surrounding_cb(void *data, Ecore_IMF_Context *ctx EINA_UNUSED, void *event_info)
{
// called when the input method needs to delete all or part of the context surrounding the cursor
Entry *en = data;
Ecore_IMF_Event_Delete_Surrounding *ev = event_info;
Evas_Textblock_Cursor *del_start, *del_end;
int cursor_pos;
if ((!en) || (!ev)) return;
// get the current cursor position
cursor_pos = evas_textblock_cursor_pos_get(en->cursor);
// start cursor position to be deleted
del_start = evas_object_textblock_cursor_new(en->txt_obj);
evas_textblock_cursor_pos_set(del_start, cursor_pos + ev->offset);
// end cursor position to be deleted
del_end = evas_object_textblock_cursor_new(en->txt_obj);
evas_textblock_cursor_pos_set(del_end, cursor_pos + ev->offset + ev->n_chars);
// implement function to delete character(s) from 'cursor_pos+ev->offset' cursor position to 'cursor_pos + ev->offset + ev->n_chars'
evas_textblock_cursor_range_delete(del_start, del_end);
evas_textblock_cursor_free(del_start);
evas_textblock_cursor_free(del_end);
}
static void
_ecore_imf_event_commit_cb(void *data, Ecore_IMF_Context *ctx EINA_UNUSED, void *event_info)
{
Entry *en = data;
char *commit_str = (char *)event_info;
if (!en) return;
// delete preedit string
_preedit_del(en);
_preedit_clear(en);
printf("commit string : %s\n", commit_str);
// insert the commit string in the editor
evas_object_textblock_text_markup_prepend(en->cursor, commit_str);
// notify the cursor information
_imf_cursor_info_set(en);
return;
}
static void
_ecore_imf_event_preedit_changed_cb(void *data, Ecore_IMF_Context *ctx, void *event_info EINA_UNUSED)
{
// example how to get preedit string
Entry *en = data;
char *preedit_string;
int cursor_pos;
Eina_List *attrs = NULL;
Eina_List *l;
Ecore_IMF_Preedit_Attr *attr;
Ecore_IMF_Context *imf_context = ctx;
int preedit_start_pos, preedit_end_pos;
int i;
Eina_Bool preedit_end_state = EINA_FALSE;
if (!en) return;
// get preedit string and attributes
ecore_imf_context_preedit_string_with_attributes_get(imf_context, &preedit_string, &attrs, &cursor_pos);
printf("preedit string : %s\n", preedit_string);
if (!strcmp(preedit_string, ""))
preedit_end_state = EINA_TRUE;
// delete preedit
_preedit_del(en);
preedit_start_pos = evas_textblock_cursor_pos_get(en->cursor);
// insert preedit character(s)
if (strlen(preedit_string) > 0)
{
if (attrs)
{
EINA_LIST_FOREACH(attrs, l, attr)
{
if (attr->preedit_type == ECORE_IMF_PREEDIT_TYPE_SUB1) // style type
{
// apply appropriate style such as underline
}
else if (attr->preedit_type == ECORE_IMF_PREEDIT_TYPE_SUB2 || attr->preedit_type == ECORE_IMF_PREEDIT_TYPE_SUB3)
{
// apply appropriate style such as underline
}
}
// insert code to display preedit string in your editor
evas_object_textblock_text_markup_prepend(en->cursor, preedit_string);
}
}
if (!preedit_end_state)
{
// set preedit start cursor
if (!en->preedit_start)
en->preedit_start = evas_object_textblock_cursor_new(en->txt_obj);
evas_textblock_cursor_copy(en->cursor, en->preedit_start);
// set preedit end cursor
if (!en->preedit_end)
en->preedit_end = evas_object_textblock_cursor_new(en->txt_obj);
evas_textblock_cursor_copy(en->cursor, en->preedit_end);
preedit_end_pos = evas_textblock_cursor_pos_get(en->cursor);
for (i = 0; i < (preedit_end_pos - preedit_start_pos); i++)
{
evas_textblock_cursor_char_prev(en->preedit_start);
}
en->have_preedit = EINA_TRUE;
// set cursor position
evas_textblock_cursor_pos_set(en->cursor, preedit_start_pos + cursor_pos);
}
// notify the cursor information
_imf_cursor_info_set(en);
EINA_LIST_FREE(attrs, attr)
free(attr);
free(preedit_string);
}
static void
_key_down_cb(void *data, Evas *e EINA_UNUSED, Evas_Object *o EINA_UNUSED, void *event_info)
{
Entry *en = data;
Evas_Event_Key_Down *ev = event_info;
Eina_Bool control, alt, shift;
if ((!en) || (!ev->key)) return;
if (en->imf_context)
{
Ecore_IMF_Event_Key_Down ecore_ev;
ecore_imf_evas_event_key_down_wrap(ev, &ecore_ev);
if (ecore_imf_context_filter_event(en->imf_context,
ECORE_IMF_EVENT_KEY_DOWN,
(Ecore_IMF_Event *)&ecore_ev))
return;
}
control = evas_key_modifier_is_set(ev->modifiers, "Control");
alt = evas_key_modifier_is_set(ev->modifiers, "Alt");
shift = evas_key_modifier_is_set(ev->modifiers, "Shift");
(void)alt;
(void)shift;
if (!strcmp(ev->key, "BackSpace"))
{
if (evas_textblock_cursor_char_prev(en->cursor))
{
evas_textblock_cursor_char_delete(en->cursor);
// notify the cursor information
_imf_cursor_info_set(en);
}
return;
}
else if (!strcmp(ev->key, "Delete") ||
(!strcmp(ev->key, "KP_Delete") && !ev->string))
{
// FILLME
}
else if ((control) && (!strcmp(ev->key, "v")))
{
// ctrl + v
// FILLME
}
else if ((control) && (!strcmp(ev->key, "a")))
{
// ctrl + a
// FILLME
}
else if ((control) && (!strcmp(ev->key, "A")))
{
// ctrl + A
// FILLME
}
else if ((control) && ((!strcmp(ev->key, "c") || (!strcmp(ev->key, "Insert")))))
{
// ctrl + c
// FILLME
}
else if ((control) && ((!strcmp(ev->key, "x") || (!strcmp(ev->key, "m")))))
{
// ctrl + x
// FILLME
}
else if ((control) && (!strcmp(ev->key, "z")))
{
// ctrl + z (undo)
// FILLME
}
else if ((control) && (!strcmp(ev->key, "y")))
{
// ctrl + y (redo)
// FILLME
}
else if ((!strcmp(ev->key, "Return")) || (!strcmp(ev->key, "KP_Enter")))
{
// FILLME
}
else
{
if (ev->string)
{
printf("key down string : %s\n", ev->string);
evas_object_textblock_text_markup_prepend(en->cursor, ev->string);
}
}
// notify the cursor information
_imf_cursor_info_set(en);
}
static void
_key_up_cb(void *data, Evas *e EINA_UNUSED, Evas_Object *o EINA_UNUSED, void *event_info)
{
Entry *en = data;
Evas_Event_Key_Up *ev = event_info;
if (!en) return;
if (en->imf_context)
{
Ecore_IMF_Event_Key_Up ecore_ev;
ecore_imf_evas_event_key_up_wrap(ev, &ecore_ev);
if (ecore_imf_context_filter_event(en->imf_context,
ECORE_IMF_EVENT_KEY_UP,
(Ecore_IMF_Event *)&ecore_ev))
return;
}
}
static void
create_input_field(Evas *evas, Entry *en, Evas_Coord x, Evas_Coord y, Evas_Coord w, Evas_Coord h)
{
if (!en) return;
en->have_preedit = EINA_FALSE;
en->preedit_start = NULL;
en->preedit_end = NULL;
// create the background for text input field
en->rect = evas_object_rectangle_add(evas);
evas_object_color_set(en->rect, 150, 150, 150, 255); // gray color
evas_object_move(en->rect, x, y);
evas_object_resize(en->rect, w, h);
evas_object_show(en->rect);
evas_object_data_set(en->rect, "Entry", en);
// create text object for displaying text
en->txt_obj = evas_object_textblock_add(evas);
evas_object_color_set(en->txt_obj, 0, 0, 0, 255);
evas_object_pass_events_set(en->txt_obj, EINA_TRUE);
evas_object_move(en->txt_obj, x, y);
evas_object_resize(en->txt_obj, w, h);
evas_object_show(en->txt_obj);
// set style on textblock
static const char *style_buf =
"DEFAULT='font=Sans font_size=30 color=#000 text_class=entry'"
"newline='br'"
"b='+ font=Sans:style=bold'";
en->txt_style = evas_textblock_style_new();
evas_textblock_style_set(en->txt_style, style_buf);
evas_object_textblock_style_set(en->txt_obj, en->txt_style);
// create cursor
en->cursor = evas_object_textblock_cursor_new(en->txt_obj);
// create input context
const char *default_id = ecore_imf_context_default_id_get();
if (!default_id)
return;
en->imf_context = ecore_imf_context_add(default_id);
ecore_imf_context_client_window_set(en->imf_context, (void *)ecore_evas_window_get(ecore_evas_ecore_evas_get(evas)));
ecore_imf_context_client_canvas_set(en->imf_context, evas);
// register key event handler
evas_object_event_callback_add(en->rect, EVAS_CALLBACK_KEY_DOWN, _key_down_cb, en);
evas_object_event_callback_add(en->rect, EVAS_CALLBACK_KEY_UP, _key_up_cb, en);
// register mouse event handler
evas_object_event_callback_add(en->rect, EVAS_CALLBACK_MOUSE_DOWN, _mouse_down_cb, en);
evas_object_event_callback_add(en->rect, EVAS_CALLBACK_MOUSE_UP, _mouse_up_cb, en);
// register focus event handler
evas_object_event_callback_add(en->rect, EVAS_CALLBACK_FOCUS_IN, _entry_focus_in_cb, en);
evas_object_event_callback_add(en->rect, EVAS_CALLBACK_FOCUS_OUT, _entry_focus_out_cb, en);
// register retrieve surrounding callback
ecore_imf_context_retrieve_surrounding_callback_set(en->imf_context, _ecore_imf_retrieve_surrounding_cb, en);
// register commit event callback
ecore_imf_context_event_callback_add(en->imf_context, ECORE_IMF_CALLBACK_COMMIT, _ecore_imf_event_commit_cb, en);
// register preedit changed event handler
ecore_imf_context_event_callback_add(en->imf_context, ECORE_IMF_CALLBACK_PREEDIT_CHANGED, _ecore_imf_event_preedit_changed_cb, en);
// register surrounding delete event callback
ecore_imf_context_event_callback_add(en->imf_context, ECORE_IMF_CALLBACK_DELETE_SURROUNDING, _ecore_imf_event_delete_surrounding_cb, en);
}
static void
delete_input_field(Entry *en)
{
if (!en) return;
if (en->rect)
{
evas_object_del(en->rect);
en->rect = NULL;
}
if (en->cursor)
{
evas_textblock_cursor_free(en->cursor);
en->cursor = NULL;
}
if (en->preedit_start)
{
evas_textblock_cursor_free(en->preedit_start);
en->preedit_start = NULL;
}
if (en->preedit_end)
{
evas_textblock_cursor_free(en->preedit_end);
en->preedit_end = NULL;
}
if (en->txt_obj)
{
evas_object_del(en->txt_obj);
en->txt_obj = NULL;
}
if (en->txt_style)
{
evas_textblock_style_free(en->txt_style);
en->txt_style = NULL;
}
if (en->imf_context)
{
ecore_imf_context_del(en->imf_context);
en->imf_context = NULL;
}
}
int
main(void)
{
Ecore_Evas *ee;
Evas *evas;
Entry en1, en2;
if (!ecore_evas_init())
{
fprintf(stderr, "failed to call ecore_evas_init()\n");
return EXIT_FAILURE;
}
ecore_imf_init();
// create a new window, with size=WIDTHxHEIGHT and default engine
ee = ecore_evas_new(NULL, 0, 0, WIDTH, HEIGHT, NULL);
if (!ee)
{
fprintf(stderr, "failed to call ecore_evas_new\n");
return EXIT_FAILURE;
}
ecore_evas_show(ee);
// get the canvas off just-created window
evas = ecore_evas_get(ee);
if (!evas)
{
fprintf(stderr, "failed to call ecore_evas_get\n");
return EXIT_FAILURE;
}
// create input field rectangle
Evas_Object *bg = evas_object_rectangle_add(evas);
evas_object_move(bg, 0, 0);
evas_object_resize(bg, WIDTH, HEIGHT);
evas_object_color_set(bg, 255, 255, 255, 255);
evas_object_show(bg);
// register canvas focus in/out event handler
evas_event_callback_add(evas, EVAS_CALLBACK_CANVAS_FOCUS_IN, _canvas_focus_in_cb, NULL);
evas_event_callback_add(evas, EVAS_CALLBACK_CANVAS_FOCUS_OUT, _canvas_focus_out_cb, NULL);
// create input field 1
create_input_field(evas, &en1, 40, 60, 400, 80);
// create input field 2
create_input_field(evas, &en2, 40, 180, 400, 80);
// give focus to input field 1
evas_object_focus_set(en1.rect, EINA_TRUE);
ecore_main_loop_begin(); // begin mainloop
delete_input_field(&en1); // delete input field 1
delete_input_field(&en2); // delete input field 2
evas_event_callback_del_full(evas, EVAS_CALLBACK_CANVAS_FOCUS_IN, _canvas_focus_in_cb, NULL);
evas_event_callback_del_full(evas, EVAS_CALLBACK_CANVAS_FOCUS_OUT, _canvas_focus_out_cb, NULL);
ecore_evas_free(ee);
ecore_imf_shutdown();
ecore_evas_shutdown();
return 0;
}