perf(label): reduce lv_label_refr_text calls (#9041)

Signed-off-by: yushuailong1 <yushuailong1@xiaomi.com>

src/core/lv_obj_pos.c

@@ -35,7 +35,7 @@ static int32_t calc_content_height(lv_obj_t * obj);
 static void layout_update_core(lv_obj_t * obj);
 static void transform_point_array(const lv_obj_t * obj, lv_point_t * p, size_t p_count, bool inv);
 static bool is_transformed(const lv_obj_t * obj);
-
+static lv_obj_tree_walk_res_t update_layout_completed_cb(lv_obj_t * obj, void * user_data);
 /**********************
  *  STATIC VARIABLES
  **********************/
@@ -304,6 +304,12 @@ void lv_obj_mark_layout_as_dirty(lv_obj_t * obj)
     lv_display_send_event(disp, LV_EVENT_REFR_REQUEST, NULL);
 }
 
+void lv_obj_request_layout_complete_event(lv_obj_t * obj)
+{
+    lv_obj_t * scr = lv_obj_get_screen(obj);
+    scr->scr_layout_complete_pending = 1;
+}
+
 void lv_obj_update_layout(const lv_obj_t * obj)
 {
     if(update_layout_mutex) {
@@ -322,6 +328,11 @@ void lv_obj_update_layout(const lv_obj_t * obj)
         LV_LOG_TRACE("Layout update end");
     }
 
+    if(scr->scr_layout_complete_pending) {
+        scr->scr_layout_complete_pending = 0;
+        lv_obj_tree_walk(scr, update_layout_completed_cb, NULL);
+    }
+
     update_layout_mutex = false;
     LV_PROFILER_LAYOUT_END;
 }
@@ -1316,3 +1327,10 @@ static void transform_point_array(const lv_obj_t * obj, lv_point_t * p, size_t p
 
     lv_point_array_transform(p, p_count, angle, scale_x, scale_y, &pivot, !inv);
 }
+
+static lv_obj_tree_walk_res_t update_layout_completed_cb(lv_obj_t * obj, void * user_data)
+{
+    LV_UNUSED(user_data);
+    lv_obj_send_event(obj, LV_EVENT_UPDATE_LAYOUT_COMPLETED, NULL);
+    return LV_OBJ_TREE_WALK_NEXT;
+}

src/core/lv_obj_pos.h

@@ -153,6 +153,12 @@ bool lv_obj_is_layout_positioned(const lv_obj_t * obj);
  */
 void lv_obj_mark_layout_as_dirty(lv_obj_t * obj);
 
+/**
+ * Mark screen to send layout completed event after update.
+ * @param obj   Any object on the target screen
+ */
+void lv_obj_request_layout_complete_event(lv_obj_t * obj);
+
 /**
  * Update the layout of an object.
  * @param obj      pointer to an object whose position and size needs to be updated

src/core/lv_obj_private.h

@@ -71,6 +71,7 @@ struct _lv_obj_t {
     uint16_t layout_inv : 1;
     uint16_t readjust_scroll_after_layout : 1;
     uint16_t scr_layout_inv : 1;
+    uint16_t scr_layout_complete_pending : 1;
     uint16_t skip_trans : 1;
     uint16_t style_cnt  : 6;
     uint16_t h_layout   : 1;

src/misc/lv_event.c

@@ -353,6 +353,7 @@ const char * lv_event_code_get_name(lv_event_code_t code)
             ENUM_CASE(EVENT_STYLE_CHANGED);
             ENUM_CASE(EVENT_LAYOUT_CHANGED);
             ENUM_CASE(EVENT_GET_SELF_SIZE);
+            ENUM_CASE(EVENT_UPDATE_LAYOUT_COMPLETED);
 
             /** Events of optional LVGL components*/
             ENUM_CASE(EVENT_INVALIDATE_AREA);

src/misc/lv_event.h

@@ -93,6 +93,7 @@ typedef enum {
     LV_EVENT_STYLE_CHANGED,       /**< Object's style has changed */
     LV_EVENT_LAYOUT_CHANGED,      /**< A child's position position has changed due to a layout recalculation */
     LV_EVENT_GET_SELF_SIZE,       /**< Get internal size of a widget */
+    LV_EVENT_UPDATE_LAYOUT_COMPLETED,    /**< Sent after layout update completes*/
 
     /** Events of optional LVGL components */
     LV_EVENT_INVALIDATE_AREA,     /**< An area is invalidated (marked for redraw). `lv_event_get_param(e)`

src/widgets/label/lv_label.c

@@ -62,7 +62,7 @@ static void copy_text_to_label(lv_label_t * label, const char * text);
 static lv_text_flag_t get_label_flags(lv_label_t * label);
 static void calculate_x_coordinate(int32_t * x, const lv_text_align_t align, const char * txt,
                                    uint32_t length, const lv_font_t * font, lv_area_t * txt_coords, lv_text_attributes_t * attributes);
-
+static void lv_label_mark_need_refr_text(lv_obj_t * obj);
 #if LV_USE_OBSERVER
     static void label_text_observer_cb(lv_observer_t * observer, lv_subject_t * subject);
 #endif
@@ -166,7 +166,7 @@ void lv_label_set_text_vfmt(lv_obj_t * obj, const char * fmt, va_list args)
 
     /*If text is NULL then refresh*/
     if(fmt == NULL) {
-        lv_label_refr_text(obj);
+        lv_label_mark_need_refr_text(obj);
         return;
     }
 
@@ -178,7 +178,7 @@ void lv_label_set_text_vfmt(lv_obj_t * obj, const char * fmt, va_list args)
     label->text = lv_text_set_text_vfmt(fmt, args);
     label->static_txt = 0; /*Now the text is dynamically allocated*/
 
-    lv_label_refr_text(obj);
+    lv_label_mark_need_refr_text(obj);
 }
 
 void lv_label_set_text_static(lv_obj_t * obj, const char * text)
@@ -197,7 +197,7 @@ void lv_label_set_text_static(lv_obj_t * obj, const char * text)
         label->text       = (char *)text;
     }
 
-    lv_label_refr_text(obj);
+    lv_label_mark_need_refr_text(obj);
 }
 
 #if LV_USE_TRANSLATION
@@ -240,7 +240,7 @@ void lv_label_set_long_mode(lv_obj_t * obj, lv_label_long_mode_t long_mode)
         label->expand = 0;
 
     label->long_mode = long_mode;
-    lv_label_refr_text(obj);
+    lv_label_mark_need_refr_text(obj);
 }
 
 void lv_label_set_text_selection_start(lv_obj_t * obj, uint32_t index)
@@ -281,7 +281,7 @@ void lv_label_set_recolor(lv_obj_t * obj, bool en)
     label->recolor = en == false ? 0 : 1;
 
     /*Refresh the text because the potential color codes in text needs to be hidden or revealed*/
-    lv_label_refr_text(obj);
+    lv_label_mark_need_refr_text(obj);
 }
 
 /*=====================
@@ -740,7 +740,7 @@ void lv_label_cut_text(lv_obj_t * obj, uint32_t pos, uint32_t cnt)
     lv_text_cut(label_txt, pos, cnt);
 
     /*Refresh the label*/
-    lv_label_refr_text(obj);
+    lv_label_mark_need_refr_text(obj);
 }
 
 
@@ -806,7 +806,7 @@ static void lv_label_event(const lv_obj_class_t * class_p, lv_event_t * e)
     lv_obj_t * obj = lv_event_get_current_target(e);
 
     if((code == LV_EVENT_STYLE_CHANGED) || (code == LV_EVENT_SIZE_CHANGED)) {
-        lv_label_refr_text(obj);
+        lv_label_mark_need_refr_text(obj);
     }
     else if(code == LV_EVENT_REFR_EXT_DRAW_SIZE) {
         /* Italic or other non-typical letters can be drawn of out of the object.
@@ -859,6 +859,9 @@ static void lv_label_event(const lv_obj_class_t * class_p, lv_event_t * e)
         draw_main(e);
 
     }
+    else if(code == LV_EVENT_UPDATE_LAYOUT_COMPLETED) {
+        lv_label_refr_text(obj);
+    }
 #if LV_USE_TRANSLATION
     else if(code == LV_EVENT_TRANSLATION_LANGUAGE_CHANGED) {
         lv_label_t * label = (lv_label_t *)obj;
@@ -1022,7 +1025,7 @@ static void set_text_internal(lv_obj_t * obj, const char * text)
         label->static_txt = 0;
     }
 
-    lv_label_refr_text(obj);
+    lv_label_mark_need_refr_text(obj);
 }
 
 static void remove_translation_tag(lv_obj_t * obj)
@@ -1062,6 +1065,18 @@ static void overwrite_anim_property(lv_anim_t * dest, const lv_anim_t * src, lv_
     }
 }
 
+static void lv_label_mark_need_refr_text(lv_obj_t * obj)
+{
+    lv_label_t * label = (lv_label_t *)obj;
+    if(label->text == NULL) return;
+    label->invalid_size_cache = true;
+    label->need_refr_text = true;
+
+    lv_obj_refresh_self_size(obj);
+
+    lv_obj_request_layout_complete_event(obj);
+}
+
 /**
  * Refresh the label with its text stored in its extended data
  * @param label pointer to a label object
@@ -1070,10 +1085,11 @@ static void lv_label_refr_text(lv_obj_t * obj)
 {
     lv_label_t * label = (lv_label_t *)obj;
     if(label->text == NULL) return;
+    if(!label->need_refr_text) return;
+    label->need_refr_text = false;
 #if LV_LABEL_LONG_TXT_HINT
     label->hint.line_start = -1; /*The hint is invalid if the text changes*/
 #endif
-    label->invalid_size_cache = true;
 
     lv_area_t txt_coords;
     lv_text_attributes_t attributes = {0};
@@ -1091,8 +1107,6 @@ static void lv_label_refr_text(lv_obj_t * obj)
     lv_text_get_size_attributes(&size, label->text, font, &attributes);
     label->text_size = size;
 
-    lv_obj_refresh_self_size(obj);
-
     /*In scroll mode start an offset animation*/
     if(label->long_mode == LV_LABEL_LONG_MODE_SCROLL) {
         const lv_anim_t * anim_template = lv_obj_get_style_anim(obj, LV_PART_MAIN);

src/widgets/label/lv_label_private.h

@@ -53,6 +53,7 @@ struct _lv_label_t {
     uint8_t recolor : 1;                /**< Enable in-line letter re-coloring*/
     uint8_t expand : 1;                 /**< Ignore real width (used by the library with LV_LABEL_LONG_MODE_SCROLL) */
     uint8_t invalid_size_cache : 1;     /**< 1: Recalculate size and update cache */
+    uint8_t need_refr_text : 1;         /**< 1: Refresh text after layout update completion */
 
     lv_point_t text_size;
 };