fix(objid): free old id before assign new one (#6697)

Signed-off-by: Neo Xu <neo.xu1990@gmail.com>

docs/others/obj_id.rst

@@ -33,6 +33,7 @@ Below APIs needed to be implemented and linked to lvgl.
 
 .. code:: c
 
+    void lv_obj_set_id(lv_obj_t * obj, void * id);
     void lv_obj_assign_id(const lv_obj_class_t * class_p, lv_obj_t * obj);
     void lv_obj_free_id(lv_obj_t * obj);
     const char * lv_obj_stringify_id(lv_obj_t * obj, char * buf, uint32_t len);

src/core/lv_obj.c

@@ -433,19 +433,13 @@ void lv_obj_null_on_delete(lv_obj_t ** obj_ptr)
 }
 
 #if LV_USE_OBJ_ID
-void lv_obj_set_id(lv_obj_t * obj, void * id)
-{
-    LV_ASSERT_NULL(obj);
-    obj->id = id;
-}
-
 void * lv_obj_get_id(const lv_obj_t * obj)
 {
     LV_ASSERT_NULL(obj);
     return obj->id;
 }
 
-lv_obj_t * lv_obj_get_child_by_id(const lv_obj_t * obj, void * id)
+lv_obj_t * lv_obj_get_child_by_id(const lv_obj_t * obj, const void * id)
 {
     if(obj == NULL) obj = lv_display_get_screen_active(NULL);
     if(obj == NULL) return NULL;

src/core/lv_obj.h

@@ -407,14 +407,14 @@ void * lv_obj_get_id(const lv_obj_t * obj);
  * @param id        the id of the child object
  * @return          pointer to the child object or NULL if not found
  */
-lv_obj_t * lv_obj_get_child_by_id(const lv_obj_t * obj, void * id);
+lv_obj_t * lv_obj_get_child_by_id(const lv_obj_t * obj, const void * id);
 
 /**
  * Assign id to object if not previously assigned.
  * This function gets called automatically when LV_OBJ_ID_AUTO_ASSIGN is enabled.
  *
  * Set `LV_USE_OBJ_ID_BUILTIN` to use the builtin method to generate object ID.
- * Otherwise, these functions including `lv_obj_[assign|free|stringify]_id` and
+ * Otherwise, these functions including `lv_obj_[set|assign|free|stringify]_id` and
  * `lv_obj_id_compare`should be implemented externally.
  *
  * @param class_p   the class this obj belongs to. Note obj->class_p is the class currently being constructed.
@@ -423,8 +423,8 @@ lv_obj_t * lv_obj_get_child_by_id(const lv_obj_t * obj, void * id);
 void lv_obj_assign_id(const lv_obj_class_t * class_p, lv_obj_t * obj);
 
 /**
- * Free resources allocated by `lv_obj_assign_id`.
- * This function gets called automatically when object is deleted.
+ * Free resources allocated by `lv_obj_assign_id` or `lv_obj_set_id`.
+ * This function is also called automatically when object is deleted.
  * @param obj   pointer to an object
  */
 void lv_obj_free_id(lv_obj_t * obj);
@@ -439,7 +439,7 @@ void lv_obj_free_id(lv_obj_t * obj);
  * @param id2: the second id
  * @return     0 if they are equal, non-zero otherwise.
  */
-int lv_obj_id_compare(void * id1, void * id2);
+int lv_obj_id_compare(const void * id1, const void * id2);
 
 /**
  * Format an object's id into a string.

src/core/lv_obj_id_builtin.c

@@ -79,9 +79,17 @@ void lv_obj_assign_id(const lv_obj_class_t * class_p, lv_obj_t * obj)
     obj->id = (void *)(lv_uintptr_t)id;
 }
 
+void lv_obj_set_id(lv_obj_t * obj, void * id)
+{
+    LV_ASSERT_NULL(obj);
+    if(obj->id) lv_obj_free_id(obj);
+    obj->id = id;
+}
+
 void lv_obj_free_id(lv_obj_t * obj)
 {
     LV_UNUSED(obj);
+    obj->id = NULL;
 }
 
 const char * lv_obj_stringify_id(lv_obj_t * obj, char * buf, uint32_t len)
@@ -106,7 +114,7 @@ void lv_objid_builtin_destroy(void)
     global->objid_count = 0;
 }
 
-int lv_obj_id_compare(void * id1, void * id2)
+int lv_obj_id_compare(const void * id1, const void * id2)
 {
     return id1 == id2 ? 0 : 1;
 }

src/core/lv_obj_property.c

@@ -133,28 +133,56 @@ lv_property_t lv_obj_get_style_property(lv_obj_t * obj, lv_prop_id_t id, uint32_
     return value;
 }
 
-lv_prop_id_t lv_obj_property_get_id(const lv_obj_t * obj, const char * name)
+lv_prop_id_t lv_style_property_get_id(const char * name)
 {
 #if LV_USE_OBJ_PROPERTY_NAME
-    const lv_obj_class_t * clz;
-    const lv_property_name_t * names;
     lv_property_name_t * found;
-
-    for(clz = obj->class_p; clz; clz = clz->base_class) {
-        names = clz->property_names;
-        if(names == NULL) {
-            /* try base class*/
-            continue;
-        }
-
-        found = lv_utils_bsearch(name, names, clz->names_count, sizeof(lv_property_name_t), property_name_compare);
-        if(found) return found->id;
-    }
-
     /*Check style property*/
     found = lv_utils_bsearch(name, lv_style_property_names, sizeof(lv_style_property_names) / sizeof(lv_property_name_t),
                              sizeof(lv_property_name_t), property_name_compare);
     if(found) return found->id;
+#else
+    LV_UNUSED(name);
+#endif
+    return LV_PROPERTY_ID_INVALID;
+}
+
+lv_prop_id_t lv_obj_class_property_get_id(const lv_obj_class_t * clz, const char * name)
+{
+#if LV_USE_OBJ_PROPERTY_NAME
+    const lv_property_name_t * names;
+    lv_property_name_t * found;
+
+    names = clz->property_names;
+    if(names == NULL) {
+        /* try base class*/
+        return LV_PROPERTY_ID_INVALID;
+    }
+
+    found = lv_utils_bsearch(name, names, clz->names_count, sizeof(lv_property_name_t), property_name_compare);
+    if(found) return found->id;
+#else
+    LV_UNUSED(obj);
+    LV_UNUSED(name);
+    LV_UNUSED(property_name_compare);
+#endif
+    return LV_PROPERTY_ID_INVALID;
+}
+
+lv_prop_id_t lv_obj_property_get_id(const lv_obj_t * obj, const char * name)
+{
+#if LV_USE_OBJ_PROPERTY_NAME
+    const lv_obj_class_t * clz;
+    lv_prop_id_t id;
+
+    for(clz = obj->class_p; clz; clz = clz->base_class) {
+        id = lv_obj_class_property_get_id(clz, name);
+        if(id != LV_PROPERTY_ID_INVALID) return id;
+    }
+
+    /*Check style property*/
+    id = lv_style_property_get_id(name);
+    if(id != LV_PROPERTY_ID_INVALID) return id;
 #else
     LV_UNUSED(obj);
     LV_UNUSED(name);

src/core/lv_obj_property.h

@@ -98,14 +98,14 @@ typedef struct {
              * E.g.
              *
              * static const lv_property_t obj_pos_x = {
-             *      .id = LV_STYLE_X,
+             *      .id = LV_PROPERTY_STYLE_X,
              *      .num = 123,
              *      .selector = LV_STATE_PRESSED,
              * }
              *
              * instead of:
              * static const lv_property_t obj_pos_x = {
-             *      .id = LV_STYLE_X,
+             *      .id = LV_PROPERTY_STYLE_X,
              *      .style.num = 123, // note this line.
              *      .selector = LV_STATE_PRESSED,
              * }
@@ -171,13 +171,28 @@ lv_property_t lv_obj_get_property(lv_obj_t * obj, lv_prop_id_t id);
 lv_property_t lv_obj_get_style_property(lv_obj_t * obj, lv_prop_id_t id, uint32_t selector);
 
 /**
- * Get the property ID by name. Requires to enable `LV_USE_OBJ_PROPERTY_NAME`.
+ * Get the property ID by name recursively to base classes. Requires to enable `LV_USE_OBJ_PROPERTY_NAME`.
  * @param obj       pointer to an object that has specified property or base class has.
  * @param name      property name
  * @return          property ID found or `LV_PROPERTY_ID_INVALID` if not found.
  */
 lv_prop_id_t lv_obj_property_get_id(const lv_obj_t * obj, const char * name);
 
+/**
+ * Get the property ID by name without check base class recursively. Requires to enable `LV_USE_OBJ_PROPERTY_NAME`.
+ * @param clz       pointer to an object class that has specified property or base class has.
+ * @param name      property name
+ * @return          property ID found or `LV_PROPERTY_ID_INVALID` if not found.
+ */
+lv_prop_id_t lv_obj_class_property_get_id(const lv_obj_class_t * clz, const char * name);
+
+/**
+ * Get the style property ID by name. Requires to enable `LV_USE_OBJ_PROPERTY_NAME`.
+ * @param name      property name
+ * @return          property ID found or `LV_PROPERTY_ID_INVALID` if not found.
+ */
+lv_prop_id_t lv_style_property_get_id(const char * name);
+
 /**********************
  *      MACROS
  **********************/

tests/src/test_cases/widgets/test_obj_property.c

@@ -272,6 +272,23 @@ void test_obj_property_name(void)
 #endif
 }
 
+void test_obj_class_property(void)
+{
+#if LV_USE_OBJ_PROPERTY && LV_USE_OBJ_PROPERTY_NAME
+    /* An image obj has align property */
+    lv_obj_t * img = lv_image_create(lv_screen_active());
+    TEST_ASSERT_EQUAL_UINT32(LV_PROPERTY_OBJ_ALIGN, lv_obj_property_get_id(img, "align"));
+
+    /* obj class has align property but image doesn't. */
+    TEST_ASSERT_EQUAL_UINT32(LV_PROPERTY_OBJ_ALIGN, lv_obj_class_property_get_id(&lv_obj_class, "align"));
+    TEST_ASSERT_EQUAL_UINT32(LV_PROPERTY_ID_INVALID, lv_obj_class_property_get_id(&lv_image_class, "align"));
+
+    /* style can also have property name that conflicts with obj */
+    TEST_ASSERT_EQUAL_UINT32(LV_PROPERTY_STYLE_X, lv_style_property_get_id("x"));
+    TEST_ASSERT_EQUAL_UINT32(LV_PROPERTY_OBJ_X, lv_obj_property_get_id(img, "x"));
+#endif
+}
+
 void test_label_properties(void)
 {
 #if LV_USE_OBJ_PROPERTY