fix(label) consider base dir lv_label_get_letter_pos in special cases

related to https://github.com/lvgl/lvgl/issues/2712#issuecomment-953463193

src/widgets/lv_label.c

@@ -348,10 +348,11 @@ void lv_label_get_letter_pos(const lv_obj_t * obj, uint32_t char_id, lv_point_t
     const char * bidi_txt;
     uint32_t visual_byte_pos;
 #if LV_USE_BIDI
+    lv_base_dir_t base_dir = lv_obj_get_style_base_dir(obj, LV_PART_MAIN);
     char * mutable_bidi_txt = NULL;
     /*Handle Bidi*/
     if(new_line_start == byte_id) {
-        visual_byte_pos = 0;
+        visual_byte_pos = base_dir == LV_BASE_DIR_RTL ? 0 : byte_id - line_start;
         bidi_txt =  &txt[line_start];
     }
     else {
@@ -359,7 +360,7 @@ void lv_label_get_letter_pos(const lv_obj_t * obj, uint32_t char_id, lv_point_t
 
         bool is_rtl;
         uint32_t visual_char_pos = _lv_bidi_get_visual_pos(&txt[line_start], &mutable_bidi_txt, new_line_start - line_start,
-                                                           lv_obj_get_style_base_dir(obj, LV_PART_MAIN), line_char_id, &is_rtl);
+                                                           base_dir, line_char_id, &is_rtl);
         bidi_txt = mutable_bidi_txt;
         if(is_rtl) visual_char_pos++;
 

src/widgets/lv_textarea.c

@@ -45,6 +45,7 @@
 static void lv_textarea_constructor(const lv_obj_class_t * class_p, lv_obj_t * obj);
 static void lv_textarea_destructor(const lv_obj_class_t * class_p, lv_obj_t * obj);
 static void lv_textarea_event(const lv_obj_class_t * class_p, lv_event_t * e);
+static void label_event_cb(lv_event_t * e);
 static void cursor_blink_anim_cb(void * obj, int32_t show);
 static void pwd_char_hider_anim(void * obj, int32_t x);
 static void pwd_char_hider_anim_ready(lv_anim_t * a);
@@ -822,6 +823,7 @@ static void lv_textarea_constructor(const lv_obj_class_t * class_p, lv_obj_t * o
     ta->label = lv_label_create(obj);
     lv_obj_set_width(ta->label, lv_pct(100));
     lv_label_set_text(ta->label, "");
+    lv_obj_add_event_cb(ta->label, label_event_cb, LV_EVENT_ALL, NULL);
     lv_obj_add_flag(obj, LV_OBJ_FLAG_SCROLL_ON_FOCUS);
     lv_textarea_set_cursor_pos(obj, 0);
 
@@ -856,27 +858,10 @@ static void lv_textarea_event(const lv_obj_class_t * class_p, lv_event_t * e)
 
     lv_event_code_t code = lv_event_get_code(e);
     lv_obj_t * obj = lv_event_get_target(e);
-    lv_textarea_t * ta = (lv_textarea_t *)obj;
 
-    if(code == LV_EVENT_STYLE_CHANGED) {
+    if(code == LV_EVENT_FOCUSED) {
-        if(ta->label) {
-            lv_label_set_text(ta->label, NULL);
-            refr_cursor_area(obj);
-            start_cursor_blink(obj);
-        }
-    }
-    else if(code == LV_EVENT_FOCUSED) {
         start_cursor_blink(obj);
     }
-    else if(code == LV_EVENT_SIZE_CHANGED) {
-        /*Set the label width according to the text area width*/
-        if(ta->label) {
-            lv_obj_set_pos(ta->label, 0, 0);
-            lv_label_set_text(ta->label, NULL); /*Refresh the label*/
-
-            refr_cursor_area(obj);
-        }
-    }
     else if(code == LV_EVENT_KEY) {
         uint32_t c = *((uint32_t *)lv_event_get_param(e)); /*uint32_t because can be UTF-8*/
         if(c == LV_KEY_RIGHT)
@@ -913,6 +898,21 @@ static void lv_textarea_event(const lv_obj_class_t * class_p, lv_event_t * e)
     }
 }
 
+static void label_event_cb(lv_event_t * e)
+{
+    lv_event_code_t code = lv_event_get_code(e);
+    lv_obj_t * label = lv_event_get_target(e);
+    lv_obj_t * ta = lv_obj_get_parent(label);
+
+    if(code == LV_EVENT_STYLE_CHANGED || code == LV_EVENT_SIZE_CHANGED) {
+        lv_label_set_text(label, NULL);
+        refr_cursor_area(ta);
+        start_cursor_blink(ta);
+    }
+}
+
+
+
 /**
  * Called to blink the cursor
  * @param ta pointer to a text area