fix(scroll) keep the scroll position on object deleted

lvgl · Jun 9, 2021 · 52edbb4 · 52edbb4
1 parent 769c4a3
commit 52edbb4
Showing 4 changed files with 48 additions and 36 deletions.
diff --git a/src/core/lv_obj_pos.c b/src/core/lv_obj_pos.c
@@ -83,7 +83,6 @@ void lv_obj_set_y(lv_obj_t * obj, lv_coord_t y)
 
 bool lv_obj_refr_size(lv_obj_t * obj)
 {
-
     LV_ASSERT_OBJ(obj, MY_CLASS);
 
     /*If the width or height is set by a layout do not modify them*/
@@ -187,34 +186,7 @@ bool lv_obj_refr_size(lv_obj_t * obj)
     /*Invalidate the new area*/
     lv_obj_invalidate(obj);
 
-    /*Be sure the bottom side is not remains scrolled in*/
-    /*With snapping the content can't be scrolled in*/
-    if(lv_obj_get_scroll_snap_y(obj) == LV_SCROLL_SNAP_NONE) {
-        lv_coord_t st = lv_obj_get_scroll_top(obj);
-        lv_coord_t sb = lv_obj_get_scroll_bottom(obj);
-        if(sb < 0 && st > 0) {
-            sb = LV_MIN(st, -sb);
-            lv_obj_scroll_by(obj, 0, sb, LV_ANIM_OFF);
-        }
-    }
-
-    if(lv_obj_get_scroll_snap_x(obj) == LV_SCROLL_SNAP_NONE) {
-        lv_coord_t sl = lv_obj_get_scroll_left(obj);
-        lv_coord_t sr = lv_obj_get_scroll_right(obj);
-        if(lv_obj_get_style_base_dir(obj, LV_PART_MAIN) != LV_BASE_DIR_RTL) {
-            /*Be sure the left side is not remains scrolled in*/
-            if(sr < 0 && sl > 0) {
-                sr = LV_MIN(sl, -sr);
-                lv_obj_scroll_by(obj, sr, 0, LV_ANIM_OFF);
-            }
-        } else {
-            /*Be sure the right side is not remains scrolled in*/
-            if(sl < 0 && sr > 0) {
-                sr = LV_MIN(sr, -sl);
-                lv_obj_scroll_by(obj, sl, 0, LV_ANIM_OFF);
-            }
-        }
-    }
+    lv_obj_readjust_scroll(obj, LV_ANIM_OFF);
 
     /*If the object was out of the parent invalidate the new scrollbar area too.
      *If it wasn't out of the parent but out now, also invalidate the srollbars*/

diff --git a/src/core/lv_obj_scroll.c b/src/core/lv_obj_scroll.c
@@ -256,7 +256,6 @@ void lv_obj_scroll_by(lv_obj_t * obj, lv_coord_t x, lv_coord_t y, lv_anim_enable
         lv_anim_set_ready_cb(&a, scroll_anim_ready_cb);
 
         if(x) {
-
             uint32_t t = lv_anim_speed_to_time((lv_disp_get_hor_res(d) * 2) >> 2, 0, x);
             if(t < SCROLL_ANIM_TIME_MIN) t = SCROLL_ANIM_TIME_MIN;
             if(t > SCROLL_ANIM_TIME_MAX) t = SCROLL_ANIM_TIME_MAX;
@@ -290,6 +289,9 @@ void lv_obj_scroll_by(lv_obj_t * obj, lv_coord_t x, lv_coord_t y, lv_anim_enable
         }
     } else {
         /*Remove pending animations*/
+        lv_res_t res;
+        res = lv_event_send(obj, LV_EVENT_SCROLL_END, NULL);
+        if(res != LV_RES_OK) return;
         lv_anim_del(obj, scroll_y_anim);
         lv_anim_del(obj, scroll_x_anim);
         scroll_by_raw(obj, x, y);
@@ -539,6 +541,38 @@ void lv_obj_scrollbar_invalidate(lv_obj_t * obj)
     if(lv_area_get_size(&ver_area) > 0) lv_obj_invalidate_area(obj, &ver_area);
 }
 
+void lv_obj_readjust_scroll(lv_obj_t * obj, lv_anim_enable_t anim_en)
+{
+    /*Be sure the bottom side is not remains scrolled in*/
+    /*With snapping the content can't be scrolled in*/
+    if(lv_obj_get_scroll_snap_y(obj) == LV_SCROLL_SNAP_NONE) {
+        lv_coord_t st = lv_obj_get_scroll_top(obj);
+        lv_coord_t sb = lv_obj_get_scroll_bottom(obj);
+        if(sb < 0 && st > 0) {
+            sb = LV_MIN(st, -sb);
+            lv_obj_scroll_by(obj, 0, sb, anim_en);
+        }
+    }
+
+    if(lv_obj_get_scroll_snap_x(obj) == LV_SCROLL_SNAP_NONE) {
+        lv_coord_t sl = lv_obj_get_scroll_left(obj);
+        lv_coord_t sr = lv_obj_get_scroll_right(obj);
+        if(lv_obj_get_style_base_dir(obj, LV_PART_MAIN) != LV_BASE_DIR_RTL) {
+            /*Be sure the left side is not remains scrolled in*/
+            if(sr < 0 && sl > 0) {
+                sr = LV_MIN(sl, -sr);
+                lv_obj_scroll_by(obj, sr, 0, anim_en);
+            }
+        } else {
+            /*Be sure the right side is not remains scrolled in*/
+            if(sl < 0 && sr > 0) {
+                sr = LV_MIN(sr, -sl);
+                lv_obj_scroll_by(obj, sl, 0, anim_en);
+            }
+        }
+    }
+}
+
 /**********************
  *   STATIC FUNCTIONS
  **********************/
@@ -666,6 +700,9 @@ static void scroll_area_into_view(const lv_area_t * area, lv_obj_t * child, lv_p
     }
 
     /*Remove any pending scroll animations.*/
+    lv_res_t res;
+    res = lv_event_send(parent, LV_EVENT_SCROLL_END, NULL);
+    if(res != LV_RES_OK) return;
     lv_anim_del(parent, scroll_x_anim);
     lv_anim_del(parent, scroll_y_anim);
 

diff --git a/src/core/lv_obj_scroll.h b/src/core/lv_obj_scroll.h
@@ -266,6 +266,13 @@ void lv_obj_get_scrollbar_area(struct _lv_obj_t * obj, lv_area_t * hor, lv_area_
  */
 void lv_obj_scrollbar_invalidate(struct _lv_obj_t * obj);
 
+/**
+ * Checked if the content is scrolled "in" and adjusts it to a normal position.
+ * @param obj       pointer to an object
+ * @param anim_en   LV_ANIM_ON/OFF
+ */
+void lv_obj_readjust_scroll(struct _lv_obj_t * obj, lv_anim_enable_t anim_en);
+
 /**********************
  *      MACROS
  **********************/

diff --git a/src/core/lv_obj_tree.c b/src/core/lv_obj_tree.c
@@ -67,12 +67,8 @@ void lv_obj_del(lv_obj_t * obj)
 
     /*Call the ancestor's event handler to the parent to notify it about the child delete*/
     if(par) {
-        /*Just to remove scroll animations if any*/
-        lv_obj_scroll_to(par, 0, 0, LV_ANIM_OFF);
-        if(par->spec_attr) {
-                par->spec_attr->scroll.x = 0;
-                par->spec_attr->scroll.y = 0;
-            }
+        lv_obj_readjust_scroll(par, LV_ANIM_OFF);
+        lv_obj_scrollbar_invalidate(par);
         lv_event_send(par, LV_EVENT_CHILD_CHANGED, NULL);
     }