This example shows how to manipulate TEXT and TEXTBLOCK parts from code.
The very first we are going to do is register a callback to react to changes in the text of our parts:  
   edje_object_text_change_cb_set(edje_obj, _on_text_change, NULL);
_on_text_change(
void *data EINA_UNUSED, 
Evas_Object *obj, 
const char *part)
- Note
- Since edje_obj represent a group we'll be notified whenever any part's text in that group changes.
We now set the text for two our two parts:  
 - Note
- Since the "part_two" part is a TEXTBLOCK we can use formatting such as <b>
And we now move on to selection issues, first thing we do is make sure the user can select text:  
   edje_object_part_text_select_allow_set(edje_obj, 
"part_two", 
EINA_TRUE);
We then select the entire text, and print the selected text:  
   printf("selection: %s\n", edje_object_part_text_selection_get(edje_obj, "part_two"));
We now unselect the entire text(set selection to none), and print the selected text:  
   edje_object_part_text_select_none(edje_obj, "part_two");
   printf("selection: %s\n", edje_object_part_text_selection_get(edje_obj, "part_two"));
Our example will look like this:
  The full source code follows: 
#ifdef HAVE_CONFIG_H
# include "config.h"
#else
# define EINA_UNUSED
#endif
#ifndef PACKAGE_DATA_DIR
#define PACKAGE_DATA_DIR "."
#endif
#include <Ecore.h>
#include <locale.h>
#include "Eo.h"
#define WIDTH  (500)
#define HEIGHT (500)
static int lang_idx = 0;
static const char *lang[] = {
  "en_IN",
  "ta_IN",
  "hi_IN"
};
static void
_on_delete(Ecore_Evas *ee EINA_UNUSED)
{
}
static void
_on_text_change(
void *data EINA_UNUSED, 
Evas_Object *obj, 
const char *part)
{
}
static void
_on_mouse_down(
void *data EINA_UNUSED, 
Evas *e EINA_UNUSED, 
Evas_Object *o, 
void *event_info EINA_UNUSED)
{
   char *env;
   lang_idx = (lang_idx + 1) % (sizeof (lang) / sizeof (lang[0]));
   fprintf(stderr, "Setting lang of this edje object to '%s'\n", lang[lang_idx]);
   env = getenv("LANGUAGE");
   setenv(
"LANGUAGE", lang[lang_idx], 1);
    edje_object_language_set(o, lang[lang_idx]);
}
static void
_on_mouse_down_text(
void *data EINA_UNUSED, 
Evas *e EINA_UNUSED, 
Evas_Object *o EINA_UNUSED, 
void *event_info EINA_UNUSED)
{
   lang_idx = (lang_idx + 1) % (sizeof (lang)/ sizeof (lang[0]));
   fprintf(stderr, "Setting lang to '%s'\n", lang[lang_idx]);
   setenv(
"LANGUAGE", lang[lang_idx], 1);
 }
int
main(int argc EINA_UNUSED, char *argv[] EINA_UNUSED)
{
   const char  *edje_file = PACKAGE_DATA_DIR"/text.edj";
   Ecore_Evas  *ee;
     return EXIT_FAILURE;
     goto shutdown_ecore_evas;
   
   if (!ee) goto shutdown_edje;
   evas_object_move(bg, 0, 0); 
   evas_object_resize(bg, WIDTH, HEIGHT); 
   edje_obj = edje_object_add(evas);
   edje_object_file_set(edje_obj, edje_file, "example_group");
   evas_object_move(edje_obj, 0, 20);
   evas_object_resize(edje_obj, WIDTH - 40, HEIGHT - 40);
   setenv(
"LANGUAGE", 
"en_IN", 1);
    edje_object_language_set(edje_obj, "en_IN");
   edje_object_text_change_cb_set(edje_obj, _on_text_change, NULL);
   edje_object_part_text_select_allow_set(edje_obj, 
"part_two", 
EINA_TRUE);
   edje_object_part_text_select_all(edje_obj, "part_two");
   printf("selection: %s\n", edje_object_part_text_selection_get(edje_obj, "part_two"));
   edje_object_part_text_select_none(edje_obj, "part_two");
   printf("selection: %s\n", edje_object_part_text_selection_get(edje_obj, "part_two"));
   edje_obj_one = edje_object_add(evas);
   edje_object_file_set(edje_obj_one, edje_file, "example_group1");
   evas_object_move(edje_obj_one, 0, 50);
   evas_object_resize(edje_obj_one, WIDTH - 40, HEIGHT - 40);
   edje_object_language_set(edje_obj_one, "en_IN");
   edje_object_text_change_cb_set(edje_obj_one, _on_text_change, NULL);
   edje_object_part_text_select_allow_set(edje_obj_one, 
"part_two", 
EINA_TRUE);
   edje_object_part_text_select_all(edje_obj_one, "part_two");
   printf("selection: %s\n", edje_object_part_text_selection_get(edje_obj_one, "part_two"));
   edje_object_part_text_select_none(edje_obj_one, "part_two");
   printf("selection: %s\n", edje_object_part_text_selection_get(edje_obj_one, "part_two"));
   
   edje_obj_two = edje_object_add(evas);
   edje_object_file_set(edje_obj_two, edje_file, "example_group2");
   evas_object_move(edje_obj_two, 0, 250);
   evas_object_resize(edje_obj_two, WIDTH - 40, HEIGHT - 40);
   edje_object_text_change_cb_set(edje_obj_two, _on_text_change, NULL);
   edje_object_part_text_select_allow_set(edje_obj_two, 
"part_two", 
EINA_TRUE);
   edje_object_part_text_select_all(edje_obj_two, "part_two");
   printf("selection: %s\n", edje_object_part_text_selection_get(edje_obj_two, "part_two"));
   edje_object_part_text_select_none(edje_obj_two, "part_two");
   printf("selection: %s\n", edje_object_part_text_selection_get(edje_obj_two, "part_two"));
   edje_obj_three = edje_object_add(evas);
   edje_object_file_set(edje_obj_three, edje_file, "example_group3");
   evas_object_move(edje_obj_three, 0, 350);
   evas_object_resize(edje_obj_three, WIDTH - 40, HEIGHT - 40);
   edje_object_text_change_cb_set(edje_obj_three, _on_text_change, NULL);
   edje_object_part_text_select_allow_set(edje_obj_three, 
"part_two", 
EINA_TRUE);
   edje_object_part_text_select_all(edje_obj_three, "part_two");
   printf("selection: %s\n", edje_object_part_text_selection_get(edje_obj_three, "part_two"));
   edje_object_part_text_select_none(edje_obj_three, "part_two");
   printf("selection: %s\n", edje_object_part_text_selection_get(edje_obj_three, "part_two"));
   return EXIT_SUCCESS;
 shutdown_edje:
 shutdown_ecore_evas:
   return EXIT_FAILURE;
}
The theme used in this example is: 
collections {
   group {
      name: "sel_group";
      parts {
         part {
            name: "rect";
            type: RECT;
            description {
               state: "default" 0.0;
               color: 0 255 0 255; /* green */
               rel1.relative: 0.0 0.0;
               rel2.relative: 1.0 1.0;
            }
         }
      }
   }
   group {
      name: "example_group";
      max: 500 500;
      min: 50 50;
      translation {
         file {
            locale: en_IN;
            source: domain_name.po; /* Can be either .po file or .mo file*/
         }
         file {
            locale: hi_IN;
            source: domain_name.po;
         }
         file {
            locale: ta_IN;
            source: domain_name.po;
         }
      }
      styles {
         style {
            name: "textblock_style_en";
            base: "font=Sans font_size=22 color=#f00 wrap=word";
            tag:  "br" "\n";
            tag:  "hilight" "+ font_weight=Bold";
            tag:  "b" "+ font_weight=Bold";
            tag:  "tab" "\t";
         }
         style {
            name: "textblock_style_ta";
            base: "font=Sans font_size=22 color=#000 wrap=word";
            tag:  "br" "\n";
            tag:  "hilight" "+ font_weight=Bold";
            tag:  "b" "+ font_weight=Bold";
            tag:  "tab" "\t";
         }
         style {
            name: "textblock_style_hi";
            base: "font=Sans font_size=22 color=#00f wrap=word";
            tag:  "br" "\n";
            tag:  "hilight" "+ font_weight=Bold";
            tag:  "b" "+ font_weight=Bold";
            tag:  "tab" "\t";
         }
      }
      parts {
         part {
            name: "part_one";
            type: TEXT;
            description {
               min: 50 50;
               state: "default" 0.0;
               color: 0 0 255 255; /* blue */
               rel1.relative: 0.5 0.0;
               rel2.relative: 0.5 0.0;
               text {
                  text : "LOADING";
                  domain: "domain_name";
                  font: "arial";
                  size: 22;
                  min: 1 1;
                  ellipsis: -1;
               }
            }
         }
         part {
            name: "part_two";
            type: TEXTBLOCK;
            select_mode: EXPLICIT;
            source: "sel_group";
            entry_mode: PLAIN;
            description {
               min: 50 50;
               state: "default" 0.0;
               rel1.relative: 0.0 0.25;
               rel2.relative: 0.5 0.0;
               text {
                  style: "textblock_style_en";
                  min: 1 1;
                  ellipsis: -1;
               }
            }
            description {
               inherit: "default" 0.0;
               state: "one" 0.0;
               text {
               style: "textblock_style_hi";
               min: 1 1;
               }
           }
           description {
               inherit: "default" 0.0;
               state: "two" 0.0;
               text {
                  style: "textblock_style_ta";
                  min: 1 1;
               }
            }
         }
      }
      programs {
         program {
            signal: "edje,language,hi_IN";
            source: "edje";
            script {
               set_state(PART:"part_two", "one", 1.0);
            }
         }
         program {
            signal: "edje,language,ta_IN";
            source: "edje";
            script {
               set_state(PART:"part_two", "two", 1.0);
            }
         }
         program {
            signal: "edje,language,en_IN";
            source: "edje";
            script {
               set_state(PART:"part_two", "default", 1.0);
            }
         }
      }
   }
   group {
      name: "example_group1";
      max: 500 500;
      min: 50 50;
      translation {
         file {
            locale: en_IN;
            source: domain_name.po;
         }
         file {
            locale: hi_IN;
            source: domain_name.po;
         }
         file {
            locale: ta_IN;
            source: domain_name.mo;
         }
      }
      styles {
         style {
            name: "textblock_style_en1";
            base: "font=Sans font_size=22 color=#f00 wrap=word";
            tag:  "br" "\n";
            tag:  "hilight" "+ font_weight=Bold";
            tag:  "b" "+ font_weight=Bold";
            tag:  "tab" "\t";
         }
         style {
            name: "textblock_style_ta1";
            base: "font=Sans font_size=22 color=#000 wrap=word";
            tag:  "br" "\n";
            tag:  "hilight" "+ font_weight=Bold";
            tag:  "b" "+ font_weight=Bold";
            tag:  "tab" "\t";
         }
         style {
            name: "textblock_style_hi1";
            base: "font=Sans font_size=22 color=#00f wrap=word";
            tag:  "br" "\n";
            tag:  "hilight" "+ font_weight=Bold";
            tag:  "b" "+ font_weight=Bold";
            tag:  "tab" "\t";
         }
      }
      parts {
         part {
            name: "part_one";
            type: TEXT;
            description {
               min: 50 50;
               state: "default" 0.0;
               color: 0 0 255 255; /* blue */
               rel1.relative: 0.5 0.25;
               rel2.relative: 0.5 0.0;
               text {
                  text : "LANG";
                  domain: "domain_name";
                  font: "arial";
                  size: 22;
                  min: 1 1;
                  ellipsis: -1;
               }
            }
         }
         part {
            name: "part_two";
            type: TEXTBLOCK;
            select_mode: EXPLICIT;
            source: "sel_group";
            entry_mode: PLAIN;
            description {
               min: 50 50;
               state: "default" 0.0;
               rel1.relative: 0.0 0.5;
               rel2.relative: 1.0 0.0;
               text {
                  style: "textblock_style_en1";
                  min: 1 1;
                  ellipsis: -1;
               }
            }
            description {
               inherit: "default" 0.0;
               state: "one" 0.0;
               text {
                  style: "textblock_style_hi1";
                  min: 1 1;
               }
            }
            description {
               inherit: "default" 0.0;
               state: "two" 0.0;
               text {
                  style: "textblock_style_ta1";
                  min: 1 1;
               }
            }
         }
      }
      programs {
         program {
            signal: "edje,language,hi_IN";
            source: "edje";
            script {
               set_state(PART:"part_two", "one", 1.0);
            }
         }
         program {
            signal: "edje,language,ta_IN";
            source: "edje";
            script {
               set_state(PART:"part_two", "two", 1.0);
            }
         }
         program {
            signal: "edje,language,en_IN";
            source: "edje";
            script {
               set_state(PART:"part_two", "default", 1.0);
            }
         }
      }
   }
   group {
      name: "example_group2";
      max: 500 500;
      min: 50 50;
      translation {
         file {
            locale: en_IN;
            source: domain_name.po;
         }
         file {
            locale: hi_IN;
            source: domain_name.po;
         }
         file {
            locale: ta_IN;
            source: domain_name.mo;
         }
      }
      styles {
         style {
            name: "textblock_style_en2";
            base: "font=Sans font_size=22 color=#f00 wrap=word";
            tag:  "br" "\n";
            tag:  "hilight" "+ font_weight=Bold";
            tag:  "b" "+ font_weight=Bold";
            tag:  "tab" "\t";
         }
         style {
            name: "textblock_style_ta2";
            base: "font=Sans font_size=22 color=#000 wrap=word";
            tag:  "br" "\n";
            tag:  "hilight" "+ font_weight=Bold";
            tag:  "b" "+ font_weight=Bold";
            tag:  "tab" "\t";
         }
         style {
            name: "textblock_style_hi2";
            base: "font=Sans font_size=22 color=#00f wrap=word";
            tag:  "br" "\n";
            tag:  "hilight" "+ font_weight=Bold";
            tag:  "b" "+ font_weight=Bold";
            tag:  "tab" "\t";
         }
      }
      parts {
         part {
            name: "part_one";
            type: TEXT;
            description {
               min: 50 50;
               state: "default" 0.0;
               color: 0 0 255 255; /* blue */
               rel1.relative: 0.5 0.25;
               rel2.relative: 0.5 0.0;
               text {
                  text : "SYSTEM LANGUAGE";
                  domain: "domain_name";
                  font: "arial";
                  size: 22;
                  min: 1 1;
                  ellipsis: -1;
               }
            }
         }
         part {
            name: "part_two";
            type: TEXTBLOCK;
            select_mode: EXPLICIT;
            source: "sel_group";
            entry_mode: PLAIN;
            description {
               min: 50 50;
               state: "default" 0.0;
               rel1.relative: 0.0 0.5;
               rel2.relative: 1.0 0.0;
               text {
                  style: "textblock_style_en2";
                  min: 1 1;
                  ellipsis: -1;
               }
            }
            description {
               inherit: "default" 0.0;
               state: "one" 0.0;
               text {   
                  style: "textblock_style_hi2";
                  min: 1 1;
               }
            }
            description {
               inherit: "default" 0.0;
               state: "two" 0.0;
               text {
                  style: "textblock_style_ta2";
                  min: 1 1;
               }
            }
         }
      }
      programs {
         program {
            signal: "edje,language,hi_IN";
            source: "edje";
            script {
               set_state(PART:"part_two", "one", 1.0);
            }
         }
         program {
            signal: "edje,language,ta_IN";
            source: "edje";
            script {
               set_state(PART:"part_two", "two", 1.0);
            }
         }
         program {
            signal: "edje,language,en_IN";
            source: "edje";
            script {
               set_state(PART:"part_two", "default", 1.0);
            }
         }
      }
   }
   group {
      name: "example_group3";
      max: 500 500;
      min: 50 50;
      translation {
         file {
            locale: en_IN;
            source: domain_name.po;
         }
         file {
            locale: hi_IN;
            source: domain_name.po;
         }
         file {
            locale: ta_IN;
            source: domain_name.mo;
         }
      }
      styles {
         style {
            name: "textblock_style_en3";
            base: "font=Sans font_size=22 color=#f00 wrap=word";
            tag:  "br" "\n";
            tag:  "hilight" "+ font_weight=Bold";
            tag:  "b" "+ font_weight=Bold";
            tag:  "tab" "\t";
         }
         style {
            name: "textblock_style_ta3";
            base: "font=Sans font_size=22 color=#000 wrap=word";
            tag:  "br" "\n";
            tag:  "hilight" "+ font_weight=Bold";
            tag:  "b" "+ font_weight=Bold";
            tag:  "tab" "\t";
         }
         style {
            name: "textblock_style_hi3";
            base: "font=Sans font_size=22 color=#00f wrap=word";
            tag:  "br" "\n";
            tag:  "hilight" "+ font_weight=Bold";
            tag:  "b" "+ font_weight=Bold";
            tag:  "tab" "\t";
         }
      }
      parts {
         part {
            name: "part_one";
            type: TEXT;
            description {
               min: 50 50;
               state: "default" 0.0;
               color: 0 0 255 255; /* blue */
               rel1.relative: 0.5 0.25;
               rel2.relative: 0.5 0.0;
               text {
                  text : "CHANGED";
                  domain: "domain_name";
                  font: "arial";
                  size: 22;
                  min: 1 1;
                  ellipsis: -1;
               }
            }
         }
         part {
            name: "part_two";
            type: TEXTBLOCK;
            select_mode: EXPLICIT;
            source: "sel_group";
            entry_mode: PLAIN;
            description {
               min: 50 50;
               state: "default" 0.0;
               rel1.relative: 0.0 0.5;
               rel2.relative: 1.0 0.0;
               text {
                  style: "textblock_style_en3";
                  min: 1 1;
                  ellipsis: -1;
               }
            }
            description {
               inherit: "default" 0.0;
               state: "one" 0.0;
               text {
                  style: "textblock_style_hi3";
                  min: 1 1;
               }
            }
            description {
               inherit: "default" 0.0;
               state: "two" 0.0;
               text {
                  style: "textblock_style_ta3";
                  min: 1 1;
               }
            }
         }
      }
      programs {
         program {
            signal: "edje,language,hi_IN";
            source: "edje";
            script {
               set_state(PART:"part_two", "one", 1.0);
            }
         }
         program {
            signal: "edje,language,ta_IN";
            source: "edje";
            script {
               set_state(PART:"part_two", "two", 1.0);
            }
         }
         program {
            signal: "edje,language,en_IN";
            source: "edje";
            script {
               set_state(PART:"part_two", "default", 1.0);
            }
         }
      }
   }
}
To compile use this command: 
* gcc -o edje-text edje-text.c -DPACKAGE_BIN_DIR=\"/Where/enlightenment/is/installed/bin\" -DPACKAGE_LIB_DIR=\"/Where/enlightenment/is/installed/lib\"
* -DPACKAGE_DATA_DIR=\"/Where/enlightenment/is/installed/share\"
* `pkg-config --cflags --libs evas ecore ecore-evas edje`
*
* edje_cc text.edc
*