diff --git a/CHANGELOG.md b/CHANGELOG.md
index 60de130b8c..cacf00b731 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,7 @@
 - fix(textarea) buffer overflow in password mode with UTF-8 characters
 - fix(textarea) cursor position after hiding character in password mode
 - fix(linemeter) draw critical lines with correct color
+- fix(lv_conf_internal) be sure Kconfig defines are always uppercase
 
 ## v7.8.1 (Plannad at 15.12.2020)
 
diff --git a/src/lv_core/lv_flex.c b/src/lv_core/lv_flex.c
index ef659eb266..5c6740494e 100644
--- a/src/lv_core/lv_flex.c
+++ b/src/lv_core/lv_flex.c
@@ -28,8 +28,8 @@ typedef struct {
  *  STATIC PROTOTYPES
  **********************/
 static void flex_update(lv_obj_t * cont, lv_obj_t * item);
-static int32_t find_track_end(lv_obj_t * cont, int32_t item_start_id, lv_coord_t max_main_size, track_t * t);
-static void children_repos(lv_obj_t * cont, int32_t item_first_id, int32_t item_last_id, lv_coord_t abs_x, lv_coord_t abs_y, lv_coord_t max_main_size, track_t * t);
+static int32_t find_track_end(lv_obj_t * cont, int32_t item_start_id, lv_coord_t item_gap, lv_coord_t max_main_size, track_t * t);
+static void children_repos(lv_obj_t * cont, int32_t item_first_id, int32_t item_last_id, lv_coord_t abs_x, lv_coord_t abs_y, lv_coord_t max_main_size, lv_coord_t item_gap, track_t * t);
 static void place_content(lv_flex_place_t place, lv_coord_t max_size, lv_coord_t content_size, lv_coord_t item_cnt, lv_coord_t * start_pos, lv_coord_t * gap);
 static lv_obj_t * get_next_item(lv_obj_t * cont, bool rev, int32_t * item_id);
 
@@ -101,12 +101,6 @@ void lv_flex_set_place(lv_flex_t * flex, lv_flex_place_t item_main_place, lv_fle
     flex->item_cross_place = item_cross_place;
 }
 
-void lv_flex_set_gap(lv_flex_t * flex, lv_coord_t main_gap, lv_coord_t cross_gap)
-{
-    flex->item_gap = main_gap;
-    flex->track_gap = cross_gap;
-}
-
 /*=====================
  * Getter functions
  *====================*/
@@ -118,6 +112,8 @@ static void flex_update(lv_obj_t * cont, lv_obj_t * item)
 
     bool rtl = lv_obj_get_base_dir(cont) == LV_BIDI_DIR_RTL ? true : false;
     bool row = f->dir == LV_FLEX_FLOW_ROW ? true : false;
+    lv_coord_t track_gap = row ? lv_obj_get_style_pad_column(cont, LV_PART_MAIN) : lv_obj_get_style_pad_row(cont, LV_PART_MAIN);
+    lv_coord_t item_gap = !row ? lv_obj_get_style_pad_column(cont, LV_PART_MAIN) : lv_obj_get_style_pad_row(cont, LV_PART_MAIN);
     /*Count the grow units and free space*/
     lv_coord_t max_main_size = (row ? lv_obj_get_width_fit(cont) : lv_obj_get_height_fit(cont));
     lv_coord_t abs_y = cont->coords.y1 + lv_obj_get_style_pad_top(cont, LV_PART_MAIN) - lv_obj_get_scroll_y(cont);
@@ -148,13 +144,13 @@ static void flex_update(lv_obj_t * cont, lv_obj_t * item)
         track_t t;
         while(track_first_item < cont->spec_attr->child_cnt && track_first_item >= 0) {
             /*Search the first item of the next row */
-            next_track_first_item = find_track_end(cont, track_first_item, max_main_size, &t);
-            total_track_cross_size += t.track_cross_size + f->track_gap;
+            next_track_first_item = find_track_end(cont, track_first_item, max_main_size, item_gap, &t);
+            total_track_cross_size += t.track_cross_size + track_gap;
             track_cnt++;
             track_first_item = next_track_first_item;
         }
 
-        if(track_cnt) total_track_cross_size -= f->track_gap;   /*No gap after the last track*/
+        if(track_cnt) total_track_cross_size -= track_gap;   /*No gap after the last track*/
 
         /* Place the tracks to get the start position
          * If the the height of the tracks is larger than the available space
@@ -174,18 +170,18 @@ static void flex_update(lv_obj_t * cont, lv_obj_t * item)
     while(track_first_item < cont->spec_attr->child_cnt && track_first_item >= 0) {
         track_t t;
         /*Search the first item of the next row */
-        next_track_first_item = find_track_end(cont, track_first_item, max_main_size, &t);
+        next_track_first_item = find_track_end(cont, track_first_item, max_main_size, item_gap, &t);
 
         if(rtl && !row) {
             *cross_pos -= t.track_cross_size;
         }
-        children_repos(cont, track_first_item, next_track_first_item, abs_x, abs_y, max_main_size, &t);
+        children_repos(cont, track_first_item, next_track_first_item, abs_x, abs_y, max_main_size, item_gap, &t);
         track_first_item = next_track_first_item;
 
         if(rtl && !row) {
-            *cross_pos -= gap + f->track_gap;
+            *cross_pos -= gap + track_gap;
         } else {
-            *cross_pos += t.track_cross_size + gap + f->track_gap;
+            *cross_pos += t.track_cross_size + gap + track_gap;
         }
     }
     LV_ASSERT_MEM_INTEGRITY();
@@ -195,7 +191,7 @@ static void flex_update(lv_obj_t * cont, lv_obj_t * item)
  *   STATIC FUNCTIONS
  **********************/
 
-static int32_t find_track_end(lv_obj_t * cont, int32_t item_start_id, lv_coord_t max_main_size, track_t * t)
+static int32_t find_track_end(lv_obj_t * cont, int32_t item_start_id, lv_coord_t max_main_size, lv_coord_t item_gap, track_t * t)
 {
     const lv_flex_t * f = cont->spec_attr->layout_dsc;
 
@@ -219,7 +215,7 @@ static int32_t find_track_end(lv_obj_t * cont, int32_t item_start_id, lv_coord_t
             grow_sum += _LV_FLEX_GET_GROW(main_size);
             grow_item_cnt++;
         } else {
-            lv_coord_t item_size = get_main_size(item) + f->item_gap;
+            lv_coord_t item_size = get_main_size(item) + item_gap;
             if(f->wrap && t->track_main_size + item_size > max_main_size) break;
             t->track_main_size += item_size;
         }
@@ -230,11 +226,11 @@ static int32_t find_track_end(lv_obj_t * cont, int32_t item_start_id, lv_coord_t
         t->item_cnt++;
     }
 
-    if(t->track_main_size > 0) t->track_main_size -= f->item_gap; /*There is no gap after the last item*/
+    if(t->track_main_size > 0) t->track_main_size -= item_gap; /*There is no gap after the last item*/
 
     if(grow_item_cnt && grow_sum) {
         lv_coord_t s = max_main_size - t->track_main_size;
-        s -= grow_item_cnt * f->item_gap;
+        s -= grow_item_cnt * item_gap;
         t->grow_unit =  s / grow_sum;
         t->track_main_size = max_main_size;  /*If there is at least one "grow item" the track takes the full space*/
     } else {
@@ -255,7 +251,7 @@ static int32_t find_track_end(lv_obj_t * cont, int32_t item_start_id, lv_coord_t
 }
 
 
-static void children_repos(lv_obj_t * cont, int32_t item_first_id, int32_t item_last_id, lv_coord_t abs_x, lv_coord_t abs_y, lv_coord_t max_main_size, track_t * t)
+static void children_repos(lv_obj_t * cont, int32_t item_first_id, int32_t item_last_id, lv_coord_t abs_x, lv_coord_t abs_y, lv_coord_t max_main_size, lv_coord_t item_gap, track_t * t)
 {
 
     const lv_flex_t * f = cont->spec_attr->layout_dsc;
@@ -318,7 +314,7 @@ static void children_repos(lv_obj_t * cont, int32_t item_first_id, int32_t item_
         }
 
         if(!(row && rtl)) {
-            main_pos += area_get_main_size(&item->coords) + f->item_gap + place_gap;
+            main_pos += area_get_main_size(&item->coords) + item_gap + place_gap;
         }
         item = get_next_item(cont, f->rev, &item_first_id);
     }
diff --git a/src/lv_core/lv_flex.h b/src/lv_core/lv_flex.h
index 5ba84ea89e..3028b19ed2 100644
--- a/src/lv_core/lv_flex.h
+++ b/src/lv_core/lv_flex.h
@@ -57,8 +57,6 @@ typedef enum {
 
 typedef struct {
     lv_layout_update_cb_t update_cb; /*The first element must be the update callback*/
-    lv_coord_t item_gap;
-    lv_coord_t track_gap;
     uint32_t dir          :2;
     uint32_t wrap         :1;
     uint32_t rev          :1;
diff --git a/src/lv_core/lv_grid.c b/src/lv_core/lv_grid.c
index bfecfec89b..349805a2e9 100644
--- a/src/lv_core/lv_grid.c
+++ b/src/lv_core/lv_grid.c
@@ -71,13 +71,6 @@ void lv_grid_set_place(lv_grid_t * grid, uint8_t col_place, uint8_t row_place)
     grid->row_place = row_place;
 }
 
-void lv_grid_set_gap(lv_grid_t * grid, lv_coord_t col_gap, uint8_t row_gap)
-{
-    grid->col_gap = col_gap;
-    grid->row_gap = row_gap;
-
-}
-
 void lv_obj_set_grid_cell(lv_obj_t * obj, lv_coord_t col_pos, lv_coord_t row_pos)
 {
     lv_obj_set_pos(obj, col_pos, row_pos);
@@ -172,14 +165,17 @@ static void calc(struct _lv_obj_t * cont, _lv_grid_calc_t * calc_out)
     calc_rows(cont, calc_out);
     calc_cols(cont, calc_out);
 
+    lv_coord_t col_gap = lv_obj_get_style_pad_column(cont, LV_PART_MAIN);
+    lv_coord_t row_gap = lv_obj_get_style_pad_row(cont, LV_PART_MAIN);
+
     bool rev = lv_obj_get_base_dir(cont) == LV_BIDI_DIR_RTL ? true : false;
     bool auto_w = cont->w_set == LV_SIZE_AUTO ? true : false;
     lv_coord_t cont_w = lv_obj_get_width_fit(cont);
-    calc_out->grid_w = grid_place(cont_w, auto_w, g->col_place, g->col_gap, calc_out->col_num, calc_out->w, calc_out->x, rev);
+    calc_out->grid_w = grid_place(cont_w, auto_w, g->col_place, col_gap, calc_out->col_num, calc_out->w, calc_out->x, rev);
 
     bool auto_h = cont->h_set == LV_SIZE_AUTO ? true : false;
     lv_coord_t cont_h = lv_obj_get_height_fit(cont);
-    calc_out->grid_h = grid_place(cont_h, auto_h, g->row_place, g->row_gap, calc_out->row_num, calc_out->h, calc_out->y, false);
+    calc_out->grid_h = grid_place(cont_h, auto_h, g->row_place, row_gap, calc_out->row_num, calc_out->h, calc_out->y, false);
 
     LV_ASSERT_MEM_INTEGRITY();
 }
@@ -220,7 +216,8 @@ static void calc_cols(lv_obj_t * cont, _lv_grid_calc_t * c)
         }
     }
 
-    cont_w -= grid->col_gap * (c->col_num - 1);
+    lv_coord_t col_gap = lv_obj_get_style_pad_column(cont, LV_PART_MAIN);
+    cont_w -= col_gap * (c->col_num - 1);
     lv_coord_t free_w = cont_w - grid_w;
 
     for(i = 0; i < c->col_num; i++) {
@@ -259,7 +256,8 @@ static void calc_rows(lv_obj_t * cont, _lv_grid_calc_t * c)
         }
     }
 
-    lv_coord_t cont_h = lv_obj_get_height_fit(cont) - grid->row_gap * (grid->row_dsc_len - 1);
+    lv_coord_t row_gap = lv_obj_get_style_pad_row(cont, LV_PART_MAIN);
+    lv_coord_t cont_h = lv_obj_get_height_fit(cont) - row_gap * (grid->row_dsc_len - 1);
     lv_coord_t free_h = cont_h - grid_h;
 
     for(i = 0; i < grid->row_dsc_len; i++) {
diff --git a/src/lv_core/lv_grid.h b/src/lv_core/lv_grid.h
index 791a0ca4c0..dada774e8c 100644
--- a/src/lv_core/lv_grid.h
+++ b/src/lv_core/lv_grid.h
@@ -62,8 +62,6 @@ typedef struct {
     const lv_coord_t * row_dsc;
     uint8_t col_dsc_len;
     uint8_t row_dsc_len;
-    lv_coord_t col_gap;
-    lv_coord_t row_gap;
     uint8_t col_place;
     uint8_t row_place;
 }lv_grid_t;
diff --git a/src/lv_core/lv_obj.c b/src/lv_core/lv_obj.c
index 765741f47b..9b785fae71 100644
--- a/src/lv_core/lv_obj.c
+++ b/src/lv_core/lv_obj.c
@@ -218,22 +218,26 @@ void lv_deinit(void)
  */
 lv_obj_t * lv_obj_create(lv_obj_t * parent, const lv_obj_t * copy)
 {
-    lv_obj_t * obj = lv_mem_alloc(sizeof(lv_obj_t));
-    _lv_memset_00(obj, sizeof(lv_obj_t));
-    obj->class_p = &lv_obj;
-
-    lv_obj.constructor(obj, parent, copy);
-
-    lv_obj_create_finish(obj, parent, copy);
-
-    return obj;
+    return lv_obj_create_from_class(&lv_obj, parent, copy);
 }
 
-
-void lv_obj_create_finish(lv_obj_t * obj, lv_obj_t * parent, const lv_obj_t * copy)
+lv_obj_t * lv_obj_create_from_class(lv_obj_class_t * class, lv_obj_t * parent, const lv_obj_t * copy)
 {
+    lv_obj_t * obj = lv_mem_alloc(sizeof(lv_obj_t));
+    _lv_memset_00(obj, sizeof(lv_obj_t));
+    obj->class_p = class;
+
+    if(obj->class_p->ext_size) {
+        obj->ext_attr = lv_mem_alloc(obj->class_p->ext_size);
+        _lv_memset_00(obj->ext_attr, obj->class_p->ext_size);
+    }
+
+    class->constructor(obj, parent, copy);
+
     if(!copy) lv_theme_apply(obj);
 //    else lv_style_list_copy(&checkbox->style_indic, &checkbox_copy->style_indic);
+
+    return obj;
 }
 
 /**
@@ -1832,8 +1836,7 @@ static lv_res_t lv_obj_signal(lv_obj_t * obj, lv_signal_t sign, void * param)
         *s = LV_MATH_MAX(*s, d);
     }
     else if(sign == LV_SIGNAL_STYLE_CHG) {
-        /* Padding might have changed so the layout should be recalculated
-         * If margin has also changed the parent's layout also needs to be updated but it's done in CHILD_CHG signal*/
+        /* Padding might have changed so the layout should be recalculated*/
         lv_obj_update_layout(obj, NULL);
 
         /*Reposition non grid objects on by one*/
diff --git a/src/lv_core/lv_obj.h b/src/lv_core/lv_obj.h
index f8673697b2..638291e5c3 100644
--- a/src/lv_core/lv_obj.h
+++ b/src/lv_core/lv_obj.h
@@ -300,6 +300,9 @@ void lv_deinit(void);
 lv_obj_t * lv_obj_create(lv_obj_t * parent, const lv_obj_t * copy);
 
 void lv_obj_create_finish(lv_obj_t * obj, lv_obj_t * parent, const lv_obj_t * copy);
+
+lv_obj_t * lv_obj_create_from_class(lv_obj_class_t * class, lv_obj_t * parent, const lv_obj_t * copy);
+
 /**
  * Delete 'obj' and all of its children
  * @param obj pointer to an object to delete
diff --git a/src/lv_core/lv_obj_pos.c b/src/lv_core/lv_obj_pos.c
index 5a41607243..66d901b648 100644
--- a/src/lv_core/lv_obj_pos.c
+++ b/src/lv_core/lv_obj_pos.c
@@ -49,6 +49,7 @@ void lv_obj_update_layout(lv_obj_t * cont, lv_obj_t * item)
 {
     if(cont->spec_attr == NULL) return;
     if(cont->spec_attr->layout_dsc == NULL) return;
+    if(cont->spec_attr->child_cnt == 0) return;
 
     const lv_layout_base_t * layout = cont->spec_attr->layout_dsc;
     if(layout->update_cb == NULL) return;
diff --git a/src/lv_core/lv_obj_style.c b/src/lv_core/lv_obj_style.c
index 36c0253fb7..0e4a9a6508 100644
--- a/src/lv_core/lv_obj_style.c
+++ b/src/lv_core/lv_obj_style.c
@@ -425,7 +425,6 @@ void _lv_obj_refresh_style(lv_obj_t * obj,lv_style_prop_t prop)
     lv_obj_invalidate(obj);
     if(prop == LV_STYLE_PROP_ALL || (prop & LV_STYLE_PROP_LAYOUT_REFR)) {
         lv_signal_send(obj, LV_SIGNAL_STYLE_CHG, NULL);
-        lv_signal_send(obj->parent, LV_SIGNAL_CHILD_CHG, obj);
         lv_obj_invalidate(obj);
     } else if(prop & LV_STYLE_PROP_EXT_DRAW) {
         _lv_obj_refresh_ext_draw_pad(obj);
diff --git a/src/lv_core/lv_obj_style.h b/src/lv_core/lv_obj_style.h
index 81e3d3623f..8ab7cd1e64 100644
--- a/src/lv_core/lv_obj_style.h
+++ b/src/lv_core/lv_obj_style.h
@@ -244,6 +244,12 @@ static inline lv_coord_t lv_obj_get_style_pad_left(const struct _lv_obj_t * obj,
 static inline lv_coord_t lv_obj_get_style_pad_right(const struct _lv_obj_t * obj, uint32_t part) {
   lv_style_value_t v = lv_obj_get_style_prop(obj, part, LV_STYLE_PAD_RIGHT); return v.num; }
 
+static inline lv_coord_t lv_obj_get_style_pad_row(const struct _lv_obj_t * obj, uint32_t part) {
+  lv_style_value_t v = lv_obj_get_style_prop(obj, part, LV_STYLE_PAD_ROW); return v.num; }
+
+static inline lv_coord_t lv_obj_get_style_pad_column(const struct _lv_obj_t * obj, uint32_t part) {
+  lv_style_value_t v = lv_obj_get_style_prop(obj, part, LV_STYLE_PAD_COLUMN); return v.num; }
+
 static inline lv_color_t lv_obj_get_style_bg_color(const struct _lv_obj_t * obj, uint32_t part) {
   lv_style_value_t v = lv_obj_get_style_prop(obj, part, LV_STYLE_BG_COLOR); return v.color; }
 
diff --git a/src/lv_core/lv_style.c b/src/lv_core/lv_style.c
index c773e639c0..86e7974091 100644
--- a/src/lv_core/lv_style.c
+++ b/src/lv_core/lv_style.c
@@ -71,7 +71,7 @@ void lv_style_init(lv_style_t * style)
 
 uint16_t lv_style_register_prop(bool inherit)
 {
-    static uint16_t act_id = (uint16_t)_LV_STYLE_LAST_BUIL_IN_PROP;
+    static uint16_t act_id = (uint16_t)_LV_STYLE_LAST_BUILT_IN_PROP;
     act_id++;
     if(inherit) return act_id | LV_STYLE_PROP_INHERIT;
     else return act_id;
@@ -444,10 +444,20 @@ static void set_prop(lv_style_t * style, lv_style_prop_t prop, lv_style_value_t
          } else {
              _alloc_ext(style);
              style->ext->pad_right = value.num;
-             style->ext->pad_right = 1;
+             style->ext->has.pad_right = 1;
              style->pad_right = 0;
          }
          break;
+     case LV_STYLE_PAD_ROW:
+         _alloc_ext(style);
+         style->ext->pad_row = value.num;
+         style->ext->has.pad_row = 1;
+         break;
+     case LV_STYLE_PAD_COLUMN:
+         _alloc_ext(style);
+         style->ext->pad_column = value.num;
+         style->ext->has.pad_column = 1;
+         break;
 
      case LV_STYLE_BG_COLOR:
          id= style->dont_index ? 0 : alloc_index_color(value);
@@ -862,6 +872,12 @@ static bool get_prop(const lv_style_t * style, lv_style_prop_t prop, lv_style_va
           if(style->pad_right) { value->num = buf_num[style->pad_right]; return true; }
           if(style->ext && style->ext->has.pad_top) { value->num = style->ext->pad_right; return true; }
           break;
+      case LV_STYLE_PAD_ROW:
+          if(style->ext && style->ext->has.pad_row) { value->num = style->ext->pad_row; return true; }
+          break;
+      case LV_STYLE_PAD_COLUMN:
+          if(style->ext && style->ext->has.pad_column) { value->num = style->ext->pad_column; return true; }
+          break;
 
       case LV_STYLE_BG_COLOR:
       case LV_STYLE_BG_COLOR_FILTERED:
@@ -1109,6 +1125,12 @@ static bool remove_prop(lv_style_t * style, lv_style_prop_t prop)
         style->pad_right = 0;
         if(style->ext) style->ext->has.pad_right = 0;
         break;
+    case LV_STYLE_PAD_ROW:
+        if(style->ext) style->ext->has.pad_row = 0;
+        break;
+    case LV_STYLE_PAD_COLUMN:
+        if(style->ext) style->ext->has.pad_column = 0;
+        break;
 
     case LV_STYLE_BG_COLOR:
         style->bg_color = 0;
diff --git a/src/lv_core/lv_style.h b/src/lv_core/lv_style.h
index b3e72c2926..18ca1e8b98 100644
--- a/src/lv_core/lv_style.h
+++ b/src/lv_core/lv_style.h
@@ -98,6 +98,8 @@ typedef enum {
     LV_STYLE_PAD_BOTTOM     = 21 | LV_STYLE_PROP_LAYOUT_REFR,
     LV_STYLE_PAD_LEFT       = 22 | LV_STYLE_PROP_LAYOUT_REFR,
     LV_STYLE_PAD_RIGHT      = 23 | LV_STYLE_PROP_LAYOUT_REFR,
+    LV_STYLE_PAD_ROW        = 24 | LV_STYLE_PROP_LAYOUT_REFR,
+    LV_STYLE_PAD_COLUMN     = 25 | LV_STYLE_PROP_LAYOUT_REFR,
 
     LV_STYLE_BG_COLOR        = 30,
     LV_STYLE_BG_COLOR_FILTERED = 30 | LV_STYLE_PROP_FILTER,
@@ -162,8 +164,7 @@ typedef enum {
     LV_STYLE_CONTENT_OFS_X = 102 | LV_STYLE_PROP_EXT_DRAW,
     LV_STYLE_CONTENT_OFS_Y = 103 | LV_STYLE_PROP_EXT_DRAW,
 
-
-    _LV_STYLE_LAST_BUIL_IN_PROP,
+    _LV_STYLE_LAST_BUILT_IN_PROP = 128,
 
     LV_STYLE_PROP_ALL = 0xFFFF
 }lv_style_prop_t;
@@ -204,6 +205,8 @@ typedef struct {
     int8_t pad_bottom;
     int8_t pad_left;
     int8_t pad_right;
+    int8_t pad_row;
+    int8_t pad_column;
     int8_t border_width;
     uint8_t outline_width;
     uint8_t outline_pad;
@@ -266,6 +269,8 @@ typedef struct {
         uint32_t pad_bottom:1;
         uint32_t pad_left:1;
         uint32_t pad_right:1;
+        uint32_t pad_row:1;
+        uint32_t pad_column:1;
         uint32_t border_width:1;
         uint32_t outline_width:1;
         uint32_t outline_pad:1;
@@ -449,6 +454,12 @@ static inline void lv_style_set_pad_left(lv_style_t * style, lv_coord_t value) {
 static inline void lv_style_set_pad_right(lv_style_t * style, lv_coord_t value) {
   lv_style_value_t v = {.num = value}; lv_style_set_prop(style, LV_STYLE_PAD_RIGHT, v); }
 
+static inline void lv_style_set_pad_row(lv_style_t * style, lv_coord_t value) {
+  lv_style_value_t v = {.num = value}; lv_style_set_prop(style, LV_STYLE_PAD_ROW, v); }
+
+static inline void lv_style_set_pad_column(lv_style_t * style, lv_coord_t value) {
+  lv_style_value_t v = {.num = value}; lv_style_set_prop(style, LV_STYLE_PAD_COLUMN, v); }
+
 static inline void lv_style_set_bg_color(lv_style_t * style, lv_color_t value) {
   lv_style_value_t v = {.color = value}; lv_style_set_prop(style, LV_STYLE_BG_COLOR, v); }
 
diff --git a/src/lv_misc/lv_mem.c b/src/lv_misc/lv_mem.c
index 5523a8ee16..e723a9f928 100644
--- a/src/lv_misc/lv_mem.c
+++ b/src/lv_misc/lv_mem.c
@@ -83,7 +83,6 @@ typedef struct {
  **********************/
 #if LV_MEM_CUSTOM == 0
     static uint8_t * work_mem;
-    static lv_mem_ent_t  * last_ent;
 #endif
 
 static uint32_t zero_mem;   /*Give the address of this variable if 0 byte should be allocated*/
@@ -336,21 +335,15 @@ void lv_mem_defrag(void)
     lv_mem_ent_t * e_free;
     lv_mem_ent_t * e_next;
     e_free = ent_get_next(NULL);
-    last_ent = NULL;
 
     while(1) {
         /*Search the next free entry*/
         while(e_free != NULL) {
-            if(e_free->header.s.used != 0) {
-                e_free = ent_get_next(e_free);
-            }
-            else {
-                break;
-            }
+            if(e_free->header.s.used != 0) e_free = ent_get_next(e_free);
+            else break;
         }
 
         if(e_free == NULL) return;
-        if(last_ent == NULL) last_ent = e_free;
 
         /*Joint the following free entries to the free*/
         e_next = ent_get_next(e_free);
@@ -797,8 +790,7 @@ static void * alloc_core(size_t size)
 {
     void * alloc = NULL;
 
-//    lv_mem_ent_t * e = NULL;
-    lv_mem_ent_t * e = last_ent;
+    lv_mem_ent_t * e = NULL;
 
     /* Search for a appropriate entry*/
     if(e == NULL) e = ent_get_next(NULL);
@@ -812,7 +804,6 @@ static void * alloc_core(size_t size)
 
         /* End if the alloc. is successful*/
     } while(alloc == NULL);
-    last_ent = e;
 
     return alloc;
 }
diff --git a/src/lv_widgets/lv_bar.c b/src/lv_widgets/lv_bar.c
index 8db54d8022..67b4dfcd0c 100644
--- a/src/lv_widgets/lv_bar.c
+++ b/src/lv_widgets/lv_bar.c
@@ -77,20 +77,8 @@ const lv_obj_class_t lv_bar  = {
  */
 lv_obj_t * lv_bar_create(lv_obj_t * parent, const lv_obj_t * copy)
 {
-    lv_obj_t * obj = lv_mem_alloc(sizeof(lv_obj_t));
-    _lv_memset_00(obj, sizeof(lv_obj_t));
-    obj->class_p = &lv_bar;
 
-    if(obj->class_p->ext_size) {
-        obj->ext_attr = lv_mem_alloc(sizeof(lv_bar_ext_t));
-        _lv_memset_00(obj->ext_attr, sizeof(lv_bar_ext_t));
-    }
-
-    lv_bar.constructor(obj, parent, copy);
-
-    lv_obj_create_finish(obj, parent, copy);
-
-    return obj;
+    return lv_obj_create_from_class(&lv_bar, parent, copy);
 }
 
 /*=====================
diff --git a/src/lv_widgets/lv_btn.c b/src/lv_widgets/lv_btn.c
index 4cca4b6be4..0228466c7e 100644
--- a/src/lv_widgets/lv_btn.c
+++ b/src/lv_widgets/lv_btn.c
@@ -32,12 +32,20 @@
  *  STATIC PROTOTYPES
  **********************/
 static void lv_btn_constructor(lv_obj_t * obj, lv_obj_t * parent, const lv_obj_t * copy);
-static void lv_btn_destructor(void * obj);
+static void lv_btn_destructor(lv_obj_t * obj);
+static lv_design_res_t lv_btn_design(lv_obj_t * bar, const lv_area_t * clip_area, lv_design_mode_t mode);
+static lv_res_t lv_btn_signal(lv_obj_t * bar, lv_signal_t sign, void * param);
 
 /**********************
  *  STATIC VARIABLES
  **********************/
-lv_btn_class_t lv_btn;
+const lv_obj_class_t lv_btn  = {
+    .constructor = lv_btn_constructor,
+    .destructor = lv_btn_destructor,
+    .signal_cb = lv_btn_signal,
+    .design_cb = lv_btn_design,
+    .ext_size = 0,
+};
 
 
 /**********************
@@ -57,21 +65,8 @@ lv_btn_class_t lv_btn;
  */
 lv_obj_t * lv_btn_create(lv_obj_t * parent, const lv_obj_t * copy)
 {
-
-
-    if(!lv_btn._inited) {
-         LV_CLASS_INIT(lv_btn, lv_obj);
-         lv_btn.constructor = lv_btn_constructor;
-         lv_btn.destructor = lv_btn_destructor;
-     }
-
-     lv_obj_t * obj = lv_class_new(&lv_btn);
-     lv_btn.constructor(obj, parent, copy);
-
-     lv_obj_create_finish(obj, parent, copy);
-
      LV_LOG_TRACE("button create started");
-     return obj;
+     return lv_obj_create_from_class(&lv_btn, parent, copy);
 }
 
 /*=====================
@@ -91,7 +86,7 @@ static void lv_btn_constructor(lv_obj_t * obj, lv_obj_t * parent, const lv_obj_t
     LV_LOG_TRACE("lv_btn create started");
 
     LV_CLASS_CONSTRUCTOR_BEGIN(obj, lv_btn)
-    lv_btn.base_p->constructor(obj, parent, copy);
+    lv_obj.constructor(obj, parent, copy);
 
     lv_obj_set_size(obj, LV_DPI, LV_DPI / 3);
     lv_obj_clear_flag(obj, LV_OBJ_FLAG_SCROLLABLE);
@@ -101,7 +96,7 @@ static void lv_btn_constructor(lv_obj_t * obj, lv_obj_t * parent, const lv_obj_t
     LV_LOG_INFO("btn created");
 }
 
-static void lv_btn_destructor(void * obj)
+static void lv_btn_destructor(lv_obj_t * obj)
 {
 //    lv_bar_t * bar = obj;
 //
@@ -111,7 +106,15 @@ static void lv_btn_destructor(void * obj)
 //    lv_anim_del(&bar->start_value_anim, NULL);
 //#endif
 
-    lv_btn.base_p->destructor(obj);
+//    lv_btn.base_p->destructor(obj);
+}
+static lv_design_res_t lv_btn_design(lv_obj_t * obj, const lv_area_t * clip_area, lv_design_mode_t mode)
+{
+    return lv_obj.design_cb(obj, clip_area, mode);
 }
 
+static lv_res_t lv_btn_signal(lv_obj_t * obj, lv_signal_t sign, void * param)
+{
+    return lv_obj.signal_cb(obj, sign, param);
+}
 #endif
diff --git a/src/lv_widgets/lv_btn.h b/src/lv_widgets/lv_btn.h
index 2d49d6e04b..f5bfd2a2f8 100644
--- a/src/lv_widgets/lv_btn.h
+++ b/src/lv_widgets/lv_btn.h
@@ -27,19 +27,11 @@ extern "C" {
  *      TYPEDEFS
  **********************/
 
-LV_CLASS_DECLARE_START(lv_btn, lv_obj);
+typedef struct {
 
-#define _lv_btn_constructor   void (*constructor)(struct _lv_obj_t * obj, struct _lv_obj_t * parent, const struct _lv_obj_t * copy)
+}lv_btn_ext_t;
 
-#define _lv_btn_data             \
-  _lv_obj_data                  \
-
-#define _lv_btn_class_dsc        \
-  _lv_obj_class_dsc              \
-
-LV_CLASS_DECLARE_END(lv_btn, lv_obj);
-
-extern lv_btn_class_t lv_btn;
+extern const lv_obj_class_t lv_btn;
 
 
 /**********************
diff --git a/src/lv_widgets/lv_btnmatrix.c b/src/lv_widgets/lv_btnmatrix.c
index 8a6d3c4aa2..ce90cd6c9d 100644
--- a/src/lv_widgets/lv_btnmatrix.c
+++ b/src/lv_widgets/lv_btnmatrix.c
@@ -32,7 +32,6 @@
  **********************/
 static lv_res_t lv_btnmatrix_signal(lv_obj_t * btnm, lv_signal_t sign, void * param);
 static lv_design_res_t lv_btnmatrix_design(lv_obj_t * btnm, const lv_area_t * clip_area, lv_design_mode_t mode);
-static lv_style_list_t * lv_btnmatrix_get_style(lv_obj_t * btnm, uint8_t part);
 
 static uint8_t get_button_width(lv_btnmatrix_ctrl_t ctrl_bits);
 static bool button_is_hidden(lv_btnmatrix_ctrl_t ctrl_bits);
@@ -98,10 +97,6 @@ lv_obj_t * lv_btnmatrix_create(lv_obj_t * par, const lv_obj_t * copy)
     ext->map_p          = NULL;
     ext->recolor        = 0;
     ext->one_check      = 0;
-    lv_style_list_init(&ext->style_btn);
-    lv_style_list_init(&ext->style_btn2);
-    ext->style_btn.ignore_trans = 1;
-    ext->style_btn2.ignore_trans = 1;
 
     if(ancestor_design_f == NULL) ancestor_design_f = lv_obj_get_design_cb(btnm);
 
diff --git a/src/lv_widgets/lv_btnmatrix.h b/src/lv_widgets/lv_btnmatrix.h
index 545f550cf2..881a58185e 100644
--- a/src/lv_widgets/lv_btnmatrix.h
+++ b/src/lv_widgets/lv_btnmatrix.h
@@ -53,8 +53,6 @@ typedef struct {
     const char ** map_p;                              /*Pointer to the current map*/
     lv_area_t * button_areas;                         /*Array of areas of buttons*/
     lv_btnmatrix_ctrl_t * ctrl_bits;                       /*Array of control bytes*/
-    lv_style_list_t style_btn;                        /*Styles of buttons in each state*/
-    lv_style_list_t style_btn2;                       /*Styles of buttons in each state with LV_BTNMATRIX_CTRL_TYPE_2 control*/
     uint16_t btn_cnt;                                 /*Number of button in 'map_p'(Handled by the library)*/
     uint16_t btn_id_pr;                               /*Index of the currently pressed button or LV_BTNMATRIX_BTN_NONE*/
     uint16_t btn_id_focused;                          /*Index of the currently focused button or LV_BTNMATRIX_BTN_NONE*/
diff --git a/src/lv_widgets/lv_slider.c b/src/lv_widgets/lv_slider.c
index e370dd48d5..dae341182f 100644
--- a/src/lv_widgets/lv_slider.c
+++ b/src/lv_widgets/lv_slider.c
@@ -68,24 +68,8 @@ const lv_obj_class_t lv_slider = {
  */
 lv_obj_t * lv_slider_create(lv_obj_t * parent, const lv_obj_t * copy)
 {
-    LV_LOG_TRACE("slider create started");
 
-    lv_obj_t * obj = lv_mem_alloc(sizeof(lv_obj_t));
-    _lv_memset_00(obj, sizeof(lv_obj_t));
-    obj->class_p = &lv_slider;
-
-    if(obj->class_p->ext_size) {
-        obj->ext_attr = lv_mem_alloc(sizeof(lv_slider_ext_t));
-        _lv_memset_00(obj->ext_attr, sizeof(lv_slider_ext_t));
-    }
-
-    lv_slider.constructor(obj, parent, copy);
-
-    lv_obj_create_finish(obj, parent, copy);
-
-    LV_LOG_INFO("slider created");
-
-    return obj;
+    return lv_obj_create_from_class(&lv_slider, parent, copy);
 }
 
 /*=====================