From 376da66dabcdb51c3fe583197a5245f550b4df2e Mon Sep 17 00:00:00 2001
From: Gabor Kiss-Vamosi <kisvegabor@gmail.com>
Date: Wed, 3 Mar 2021 21:10:49 +0100
Subject: [PATCH] feat(layout): automatically update the screen's layout in
 lv_obj_scroll_to_view

---
 examples/scroll/lv_example_scroll_3.c | 3 ---
 src/lv_core/lv_obj_pos.c              | 5 +++--
 src/lv_core/lv_obj_scroll.c           | 6 ++++++
 src/lv_core/lv_refr.c                 | 5 -----
 4 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/examples/scroll/lv_example_scroll_3.c b/examples/scroll/lv_example_scroll_3.c
index c0869507d..9d2d64d45 100644
--- a/examples/scroll/lv_example_scroll_3.c
+++ b/examples/scroll/lv_example_scroll_3.c
@@ -14,9 +14,6 @@ static void float_btn_event_cb(lv_obj_t * float_btn, lv_event_t e)
 
         lv_obj_move_foreground(float_btn);
 
-        /* Layouts are only recalculated later but we need to know the updated position of the new button
-         * to scroll to it. */
-        lv_obj_update_layout(list);
         lv_obj_scroll_to_view(list_btn, LV_ANIM_ON);
     }
 }
diff --git a/src/lv_core/lv_obj_pos.c b/src/lv_core/lv_obj_pos.c
index 23a2264be..27ab23804 100644
--- a/src/lv_core/lv_obj_pos.c
+++ b/src/lv_core/lv_obj_pos.c
@@ -188,8 +188,9 @@ void lv_obj_update_layout(lv_obj_t * obj)
     }while(scr->layout_inv);  /*Repeat until there where layout invalidations*/
 
     /* Restore the global state because other calls of this function needs this info too.
-     * Other calls might use different start object, but they need to know if there is dirty layout somewhere.*/
-    scr->layout_inv = 1;
+     * Other calls might use different start object, but they need to know if there is dirty layout somewhere.
+     * However if the screen was updated it's sure that all layouts are ready. */
+    if(obj != scr) scr->layout_inv = 1;
 
 }
 
diff --git a/src/lv_core/lv_obj_scroll.c b/src/lv_core/lv_obj_scroll.c
index c968cb3db..705c52918 100644
--- a/src/lv_core/lv_obj_scroll.c
+++ b/src/lv_core/lv_obj_scroll.c
@@ -338,12 +338,18 @@ void lv_obj_scroll_to_y(lv_obj_t * obj, lv_coord_t y, lv_anim_enable_t anim_en)
 
 void lv_obj_scroll_to_view(lv_obj_t * obj, lv_anim_enable_t anim_en)
 {
+    /*Be sure the screens layout is correct*/
+    lv_obj_update_layout(lv_obj_get_screen(obj));
+
     lv_point_t p = {0, 0};
     scroll_area_into_view(&obj->coords, obj, &p, anim_en);
 }
 
 void lv_obj_scroll_to_view_recursive(lv_obj_t * obj, lv_anim_enable_t anim_en)
 {
+    /*Be sure the screens layout is correct*/
+    lv_obj_update_layout(lv_obj_get_screen(obj));
+
     lv_point_t p = {0, 0};
     lv_obj_t * child = obj;
     lv_obj_t * parent = lv_obj_get_parent(child);
diff --git a/src/lv_core/lv_refr.c b/src/lv_core/lv_refr.c
index 5fbafe688..0ed7882ee 100644
--- a/src/lv_core/lv_refr.c
+++ b/src/lv_core/lv_refr.c
@@ -203,15 +203,10 @@ void _lv_disp_refr_timer(lv_timer_t * tmr)
     uint32_t i;
     for(i = 0; i < disp_refr->screen_cnt; i++) {
         lv_obj_update_layout(disp_refr->screens[i]);
-        disp_refr->screens[i]->layout_inv = 0;
     }
 
     lv_obj_update_layout(disp_refr->top_layer);
-    disp_refr->top_layer->layout_inv = 0;
-
     lv_obj_update_layout(disp_refr->sys_layer);
-    disp_refr->sys_layer->layout_inv = 0;
-
 
     /*Do nothing if there is no active screen*/
     if(disp_refr->act_scr == NULL) {